During the final stage of World War II, the
United States detonated two nuclear weapons
over the Japanese cities of Hiroshima and
Nagasaki on August 6 and 9, 1945, respectively,
with the consent of the United Kingdom, as
required by the Quebec Agreement.
The two bombings killed 129,000–226,000
people, most of whom were civilians, and remain
the only use of nuclear weapons in the history
of armed conflict.
In the final year of the war, the Allies prepared
for what was anticipated to be a very costly
invasion of the Japanese mainland.
This undertaking was preceded by a conventional
and firebombing campaign that devastated 67
Japanese cities.
The war in Europe had concluded when Germany
signed its instrument of surrender on May
8, 1945.
As the Allies turned their full attention
to the Pacific theater, Japan faced the same
fate.
The Allies called for the unconditional surrender
of the Imperial Japanese armed forces in the
Potsdam Declaration on July 26, 1945—the
alternative being "prompt and utter destruction".
Japan ignored the ultimatum and the war continued.
By August 1945, the Allies' Manhattan Project
had produced two types of atomic bombs, and
the 509th Composite Group of the United States
Army Air Forces (USAAF) was equipped with
the specialized Silverplate version of the
Boeing B-29 Superfortress that could deliver
them from Tinian in the Mariana Islands.
Orders for atomic bombs to be used on four
Japanese cities were issued on July 25.
On August 6, one of the modified B-29s dropped
a uranium gun-type ("Little Boy") bomb on
Hiroshima.
Three days later, on August 9, a plutonium
implosion ("Fat Man") bomb was dropped by
another B-29 on Nagasaki.
The bombs immediately devastated their targets.
Over the next two to four months, the acute
effects of the atomic bombings killed 90,000–146,000
people in Hiroshima and 39,000–80,000 people
in Nagasaki; roughly half of the deaths in
each city occurred on the first day.
Large numbers of people continued to die from
the effects of burns, radiation sickness,
and other injuries, compounded by illness
and malnutrition, for many months afterward.
In both cities, most of the dead were civilians,
although Hiroshima had a sizable military
garrison.
On August 15—six days after the bombing
of Nagasaki and the Soviet Union's declaration
of war—Japan announced its surrender to
the Allies.
On September 2 in Tokyo Bay, the Japanese
government signed the instrument of surrender,
which effectively ended World War II.
The effects of the bombings on the social
and political character of subsequent world
history and popular culture has been studied
extensively, and the ethical and legal justification
for the bombings is still debated to this
day.
== Background ==
=== Pacific War ===
In 1945, the Pacific War between the Empire
of Japan and the Allies entered its fourth
year.
Most Japanese military units fought fiercely,
ensuring that the Allied victory would come
at an enormous cost.
The 1.25 million battle casualties incurred
in total by the United States in World War
II included both military personnel killed
in action and wounded in action.
Nearly one million of the casualties occurred
during the last year of the war, from June
1944 to June 1945.
In December 1944, American battle casualties
hit an all-time monthly high of 88,000 as
a result of the German Ardennes Offensive.
America's reserves of manpower were running
out.
Deferments for groups such as agricultural
workers were tightened, and there was consideration
of drafting women.
At the same time, the public was becoming
war-weary, and demanding that long-serving
servicemen be sent home.In the Pacific, the
Allies returned to the Philippines, recaptured
Burma, and invaded Borneo.
Offensives were undertaken to reduce the Japanese
forces remaining in Bougainville, New Guinea
and the Philippines.
In April 1945, American forces landed on Okinawa,
where heavy fighting continued until June.
Along the way, the ratio of Japanese to American
casualties dropped from 5:1 in the Philippines
to 2:1 on Okinawa.
Although some Japanese soldiers were taken
prisoner, most fought until they were killed
or committed suicide.
Nearly 99% of the 21,000 defenders of Iwo
Jima were killed.
Of the 117,000 Okinawan and Japanese troops
defending Okinawa in April–June 1945, 94%
were killed; 7,401 Japanese soldiers surrendered,
an unprecedentedly large number.As the Allies
advanced towards Japan, conditions became
steadily worse for the Japanese people.
Japan's merchant fleet declined from 5,250,000
gross tons in 1941 to 1,560,000 tons in March
1945, and 557,000 tons in August 1945.
Lack of raw materials forced the Japanese
war economy into a steep decline after the
middle of 1944.
The civilian economy, which had slowly deteriorated
throughout the war, reached disastrous levels
by the middle of 1945.
The loss of shipping also affected the fishing
fleet, and the 1945 catch was only 22% of
that in 1941.
The 1945 rice harvest was the worst since
1909, and hunger and malnutrition became widespread.
U.S. industrial production was overwhelmingly
superior to Japan's.
By 1943, the U.S. produced almost 100,000
aircraft a year, compared to Japan's production
of 70,000 for the entire war.
By the middle of 1944, the U.S. had almost
a hundred aircraft carriers in the Pacific,
far more than Japan's twenty-five for the
entire war.
In February 1945, Prince Fumimaro Konoe advised
Emperor Hirohito that defeat was inevitable,
and urged him to abdicate.
=== Preparations to invade Japan ===
Even before the surrender of Nazi Germany
on May 8, 1945, plans were underway for the
largest operation of the Pacific War, Operation
Downfall, the Allied invasion of Japan.
The operation had two parts: Operation Olympic
and Operation Coronet.
Set to begin in October 1945, Olympic involved
a series of landings by the U.S. Sixth Army
intended to capture the southern third of
the southernmost main Japanese island, Kyūshū.
Operation Olympic was to be followed in March
1946 by Operation Coronet, the capture of
the Kantō Plain, near Tokyo on the main Japanese
island of Honshū by the U.S.
First, Eighth and Tenth Armies, as well as
a Commonwealth Corps made up of Australian,
British and Canadian divisions.
The target date was chosen to allow for Olympic
to complete its objectives, for troops to
be redeployed from Europe, and the Japanese
winter to pass.
Japan's geography made this invasion plan
obvious to the Japanese; they were able to
predict the Allied invasion plans accurately
and thus adjust their defensive plan, Operation
Ketsugō, accordingly.
The Japanese planned an all-out defense of
Kyūshū, with little left in reserve for
any subsequent defense operations.
Four veteran divisions were withdrawn from
the Kwantung Army in Manchuria in March 1945
to strengthen the forces in Japan, and 45
new divisions were activated between February
and May 1945.
Most were immobile formations for coastal
defense, but 16 were high quality mobile divisions.
In all, there were 2.3 million Japanese Army
troops prepared to defend the home islands,
backed by a civilian militia of 28 million
men and women.
Casualty predictions varied widely, but were
extremely high.
The Vice Chief of the Imperial Japanese Navy
General Staff, Vice Admiral Takijirō Ōnishi,
predicted up to 20 million Japanese deaths.On
June 15, 1945, a study by the Joint War Plans
Committee, who provided planning information
to the Joint Chiefs of Staff, estimated that
Olympic would result in 130,000 to 220,000
U.S. casualties, with U.S. dead in the range
from 25,000 to 46,000.
Delivered on June 15, 1945, after insight
gained from the Battle of Okinawa, the study
noted Japan's inadequate defenses due to the
very effective sea blockade and the American
firebombing campaign.
The Chief of Staff of the United States Army,
General of the Army George Marshall, and the
Army Commander in Chief in the Pacific, General
of the Army Douglas MacArthur, signed documents
agreeing with the Joint War Plans Committee
estimate.The Americans were alarmed by the
Japanese buildup, which was accurately tracked
through Ultra intelligence.
Secretary of War Henry L. Stimson was sufficiently
concerned about high American estimates of
probable casualties to commission his own
study by Quincy Wright and William Shockley.
Wright and Shockley spoke with Colonels James
McCormack and Dean Rusk, and examined casualty
forecasts by Michael E. DeBakey and Gilbert
Beebe.
Wright and Shockley estimated the invading
Allies would suffer between 1.7 and 4 million
casualties in such a scenario, of whom between
400,000 and 800,000 would be dead, while Japanese
fatalities would have been around 5 to 10
million.Marshall began contemplating the use
of a weapon that was "readily available and
which assuredly can decrease the cost in American
lives": poison gas.
Quantities of phosgene, mustard gas, tear
gas and cyanogen chloride were moved to Luzon
from stockpiles in Australia and New Guinea
in preparation for Operation Olympic, and
MacArthur ensured that Chemical Warfare Service
units were trained in their use.
Consideration was also given to using biological
weapons against Japan.
=== Air raids on Japan ===
While the United States had developed plans
for an air campaign against Japan prior to
the Pacific War, the capture of Allied bases
in the western Pacific in the first weeks
of the conflict meant that this offensive
did not begin until mid-1944 when the long-ranged
Boeing B-29 Superfortress became ready for
use in combat.
Operation Matterhorn involved India-based
B-29s staging through bases around Chengdu
in China to make a series of raids on strategic
targets in Japan.
This effort failed to achieve the strategic
objectives that its planners had intended,
largely because of logistical problems, the
bomber's mechanical difficulties, the vulnerability
of Chinese staging bases, and the extreme
range required to reach key Japanese cities.Brigadier
General Haywood S. Hansell determined that
Guam, Tinian, and Saipan in the Mariana Islands
would better serve as B-29 bases, but they
were in Japanese hands.
Strategies were shifted to accommodate the
air war, and the islands were captured between
June and August 1944.
Air bases were developed, and B-29 operations
commenced from the Marianas in October 1944.
These bases were easily resupplied by cargo
ships.
The XXI Bomber Command began missions against
Japan on November 18, 1944.
The early attempts to bomb Japan from the
Marianas proved just as ineffective as the
China-based B-29s had been.
Hansell continued the practice of conducting
so-called high-altitude precision bombing,
aimed at key industries and transportation
networks, even after these tactics had not
produced acceptable results.
These efforts proved unsuccessful due to logistical
difficulties with the remote location, technical
problems with the new and advanced aircraft,
unfavorable weather conditions, and enemy
action.
Hansell's successor, Major General Curtis
LeMay, assumed command in January 1945 and
initially continued to use the same precision
bombing tactics, with equally unsatisfactory
results.
The attacks initially targeted key industrial
facilities but much of the Japanese manufacturing
process was carried out in small workshops
and private homes.
Under pressure from United States Army Air
Forces (USAAF) headquarters in Washington,
LeMay changed tactics and decided that low-level
incendiary raids against Japanese cities were
the only way to destroy their production capabilities,
shifting from precision bombing to area bombardment
with incendiaries.
Like most strategic bombing during World War
II, the aim of the air offensive against Japan
was to destroy the enemy's war industries,
kill or disable civilian employees of these
industries, and undermine civilian morale.Over
the next six months, the XXI Bomber Command
under LeMay firebombed 67 Japanese cities.
The firebombing of Tokyo, codenamed Operation
Meetinghouse, on March 9–10 killed an estimated
100,000 people and destroyed 16 square miles
(41 km2) of the city and 267,000 buildings
in a single night.
It was the deadliest bombing raid of the war,
at a cost of 20 B-29s shot down by flak and
fighters.
By May, 75% of bombs dropped were incendiaries
designed to burn down Japan's "paper cities".
By mid-June, Japan's six largest cities had
been devastated.
The end of the fighting on Okinawa that month
provided airfields even closer to the Japanese
mainland, allowing the bombing campaign to
be further escalated.
Aircraft flying from Allied aircraft carriers
and the Ryukyu Islands also regularly struck
targets in Japan during 1945 in preparation
for Operation Downfall.
Firebombing switched to smaller cities, with
populations ranging from 60,000 to 350,000.
According to Yuki Tanaka, the U.S. fire-bombed
over a hundred Japanese towns and cities.
These raids were devastating.The Japanese
military was unable to stop the Allied attacks
and the country's civil defense preparations
proved inadequate.
Japanese fighters and anti-aircraft guns had
difficulty engaging bombers flying at high
altitude.
From April 1945, the Japanese interceptors
also had to face American fighter escorts
based on Iwo Jima and Okinawa.
That month, the Imperial Japanese Army Air
Service and Imperial Japanese Navy Air Service
stopped attempting to intercept the air raids
to preserve fighter aircraft to counter the
expected invasion.
By mid-1945 the Japanese only occasionally
scrambled aircraft to intercept individual
B-29s conducting reconnaissance sorties over
the country, to conserve supplies of fuel.
In July 1945, the Japanese had 1,156,000 US
barrels (137,800,000 l) of avgas stockpiled
for the invasion of Japan.
About 604,000 US barrels (72,000,000 l) had
been consumed in the home islands area in
April, May and June 1945.
While the Japanese military decided to resume
attacks on Allied bombers from late June,
by this time there were too few operational
fighters available for this change of tactics
to hinder the Allied air raids.
=== Atomic bomb development ===
The discovery of nuclear fission by German
chemists Otto Hahn and Fritz Strassmann in
1938, and its theoretical explanation by Lise
Meitner and Otto Frisch, made the development
of an atomic bomb a theoretical possibility.
Fears that a German atomic bomb project would
develop atomic weapons first, especially among
scientists who were refugees from Nazi Germany
and other fascist countries, were expressed
in the Einstein-Szilard letter.
This prompted preliminary research in the
United States in late 1939.
Progress was slow until the arrival of the
British MAUD Committee report in late 1941,
which indicated that only 5 to 10 kilograms
of isotopically enriched uranium-235 were
needed for a bomb instead of tons of natural
uranium and a neutron moderator like heavy
water.The 1943 Quebec Agreement merged the
nuclear weapons projects of the United Kingdom
and Canada, Tube Alloys and the Montreal Laboratory,
with the Manhattan Project, under the direction
of Major General Leslie R. Groves, Jr., of
the U.S. Army Corps of Engineers.
Groves appointed J. Robert Oppenheimer to
organize and head the project's Los Alamos
Laboratory in New Mexico, where bomb design
work was carried out.
Two types of bombs were eventually developed,
both named by Robert Serber.
Little Boy was a gun-type fission weapon that
used uranium-235, a rare isotope of uranium
separated at the Clinton Engineer Works at
Oak Ridge, Tennessee.
The other, known as a Fat Man device, was
a more powerful and efficient, but more complicated,
implosion-type nuclear weapon that used plutonium
created in nuclear reactors at Hanford, Washington.There
was a Japanese nuclear weapon program, but
it lacked the human, mineral and financial
resources of the Manhattan Project, and never
made much progress towards developing an atomic
bomb.
== Preparations ==
=== 
Organization and training ===
The 509th Composite Group was constituted
on December 9, 1944, and activated on December
17, 1944, at Wendover Army Air Field, Utah,
commanded by Colonel Paul Tibbets.
Tibbets was assigned to organize and command
a combat group to develop the means of delivering
an atomic weapon against targets in Germany
and Japan.
Because the flying squadrons of the group
consisted of both bomber and transport aircraft,
the group was designated as a "composite"
rather than a "bombardment" unit.
Working with the Manhattan Project at Los
Alamos, Tibbets selected Wendover for his
training base over Great Bend, Kansas, and
Mountain Home, Idaho, because of its remoteness.
Each bombardier completed at least 50 practice
drops of inert or conventional explosive pumpkin
bombs and Tibbets declared his group combat-ready.
On April 5, 1945, the code name Operation
Centerboard was assigned.
The officer responsible for its allocation
in the War Department's Operations Division
was not cleared to know any details of it.
The first bombing was later codenamed Operation
Centerboard I, and the second, Operation Centerboard
II.
The 509th Composite Group had an authorized
strength of 225 officers and 1,542 enlisted
men, almost all of whom eventually deployed
to Tinian.
In addition to its authorized strength, the
509th had attached to it on Tinian 51 civilian
and military personnel from Project Alberta,
known as the 1st Technical Detachment.
The 509th Composite Group's 393d Bombardment
Squadron was equipped with 15 Silverplate
B-29s.
These aircraft were specially adapted to carry
nuclear weapons, and were equipped with fuel-injected
engines, Curtiss Electric reversible-pitch
propellers, pneumatic actuators for rapid
opening and closing of bomb bay doors and
other improvements.The ground support echelon
of the 509th Composite Group moved by rail
on April 26, 1945, to its port of embarkation
at Seattle, Washington.
On May 6 the support elements sailed on the
SS Cape Victory for the Marianas, while group
materiel was shipped on the SS Emile Berliner.
The Cape Victory made brief port calls at
Honolulu and Eniwetok but the passengers were
not permitted to leave the dock area.
An advance party of the air echelon, consisting
of 29 officers and 61 enlisted men flew by
C-54 to North Field on Tinian, between May
15 and May 22.
There were also two representatives from Washington,
D.C., Brigadier General Thomas Farrell, the
deputy commander of the Manhattan Project,
and Rear Admiral William R. Purnell of the
Military Policy Committee, who were on hand
to decide higher policy matters on the spot.
Along with Captain William S. Parsons, the
commander of Project Alberta, they became
known as the "Tinian Joint Chiefs".
=== Choice of targets ===
In April 1945, Marshall asked Groves to nominate
specific targets for bombing for final approval
by himself and Stimson.
Groves formed a Target Committee, chaired
by himself, that included Farrell, Major John
A. Derry, Colonel William P. Fisher, Joyce
C. Stearns and David M. Dennison from the
USAAF; and scientists John von Neumann, Robert
R. Wilson and William Penney from the Manhattan
Project.
The Target Committee met in Washington on
April 27; at Los Alamos on May 10, where it
was able to talk to the scientists and technicians
there; and finally in Washington on May 28,
where it was briefed by Tibbets and Commander
Frederick Ashworth from Project Alberta, and
the Manhattan Project's scientific advisor,
Richard C. Tolman.The Target Committee nominated
five targets: Kokura (now Kitakyushu), the
site of one of Japan's largest munitions plants;
Hiroshima, an embarkation port and industrial
center that was the site of a major military
headquarters; Yokohama, an urban center for
aircraft manufacture, machine tools, docks,
electrical equipment and oil refineries; Niigata,
a port with industrial facilities including
steel and aluminum plants and an oil refinery;
and Kyoto, a major industrial center.
The target selection was subject to the following
criteria:
The target was larger than 3 mi (4.8 km) in
diameter and was an important target in a
large city.
The blast would create effective damage.
The target was unlikely to be attacked by
August 1945.These cities were largely untouched
during the nightly bombing raids and the Army
Air Forces agreed to leave them off the target
list so accurate assessment of the damage
caused by the atomic bombs could be made.
Hiroshima was described as "an important army
depot and port of embarkation in the middle
of an urban industrial area.
It is a good radar target and it is such a
size that a large part of the city could be
extensively damaged.
There are adjacent hills which are likely
to produce a focusing effect which would considerably
increase the blast damage.
Due to rivers it is not a good incendiary
target."The Target Committee stated that "It
was agreed that psychological factors in the
target selection were of great importance.
Two aspects of this are (1) obtaining the
greatest psychological effect against Japan
and (2) making the initial use sufficiently
spectacular for the importance of the weapon
to be internationally recognized when publicity
on it is released.
... Kyoto has the advantage of the people
being more highly intelligent and hence better
able to appreciate the significance of the
weapon.
Hiroshima has the advantage of being such
a size and with possible focussing from nearby
mountains that a large fraction of the city
may be destroyed.
The Emperor's palace in Tokyo has a greater
fame than any other target but is of least
strategic value."Edwin O. Reischauer, a Japan
expert for the U.S. Army Intelligence Service,
was incorrectly said to have prevented the
bombing of Kyoto.
In his autobiography, Reischauer specifically
refuted this claim:
... the only person deserving credit for saving
Kyoto from destruction is Henry L. Stimson,
the Secretary of War at the time, who had
known and admired Kyoto ever since his honeymoon
there several decades earlier.
On May 30, Stimson asked Groves to remove
Kyoto from the target list due to its historical,
religious and cultural significance, but Groves
pointed to its military and industrial significance.
Stimson then approached President Harry S.
Truman about the matter.
Truman agreed with Stimson, and Kyoto was
temporarily removed from the target list.
Groves attempted to restore Kyoto to the target
list in July, but Stimson remained adamant.
On July 25, Nagasaki was put on the target
list in place of Kyoto.
It was a major military port, one of Japan's
largest shipbuilding and repair centers, and
an important producer of naval ordnance.
=== Proposed demonstration ===
In early May 1945, the Interim Committee was
created by Stimson at the urging of leaders
of the Manhattan Project and with the approval
of Truman to advise on matters pertaining
to nuclear energy.
During the meetings on May 31 and June 1,
scientist Ernest Lawrence had suggested giving
the Japanese a non-combat demonstration.
Arthur Compton later recalled that:It was
evident that everyone would suspect trickery.
If a bomb were exploded in Japan with previous
notice, the Japanese air power was still adequate
to give serious interference.
An atomic bomb was an intricate device, still
in the developmental stage.
Its operation would be far from routine.
If during the final adjustments of the bomb
the Japanese defenders should attack, a faulty
move might easily result in some kind of failure.
Such an end to an advertised demonstration
of power would be much worse than if the attempt
had not been made.
It was now evident that when the time came
for the bombs to be used we should have only
one of them available, followed afterwards
by others at all-too-long intervals.
We could not afford the chance that one of
them might be a dud.
If the test were made on some neutral territory,
it was hard to believe that Japan's determined
and fanatical military men would be impressed.
If such an open test were made first and failed
to bring surrender, the chance would be gone
to give the shock of surprise that proved
so effective.
On the contrary, it would make the Japanese
ready to interfere with an atomic attack if
they could.
Though the possibility of a demonstration
that would not destroy human lives was attractive,
no one could suggest a way in which it could
be made so convincing that it would be likely
to stop the war.
The possibility of a demonstration was raised
again in the Franck Report issued by physicist
James Franck on June 11 and the Scientific
Advisory Panel rejected his report on June
16, saying that "we can propose no technical
demonstration likely to bring an end to the
war; we see no acceptable alternative to direct
military use."
Franck then took the report to Washington,
D.C., where the Interim Committee met on June
21 to re-examine its earlier conclusions;
but it reaffirmed that there was no alternative
to the use of the bomb on a military target.Like
Compton, many U.S. officials and scientists
argued that a demonstration would sacrifice
the shock value of the atomic attack, and
the Japanese could deny the atomic bomb was
lethal, making the mission less likely to
produce surrender.
Allied prisoners of war might be moved to
the demonstration site and be killed by the
bomb.
They also worried that the bomb might be a
dud since the Trinity test was of a stationary
device, not an air-dropped bomb.
In addition, although more bombs were in production,
only two would be available at the start of
August, and they cost billions of dollars,
so using one for a demonstration would be
expensive.
=== Leaflets ===
For several months, the U.S. had warned civilians
of potential air raids by dropping more than
63 million leaflets across Japan.
Many Japanese cities suffered terrible damage
from aerial bombings; some were as much as
97% destroyed.
LeMay thought that leaflets would increase
the psychological impact of bombing, and reduce
the international stigma of area-bombing cities.
Even with the warnings, Japanese opposition
to the war remained ineffective.
In general, the Japanese regarded the leaflet
messages as truthful, with many Japanese choosing
to leave major cities.
The leaflets caused such concern that the
government ordered the arrest of anyone caught
in possession of a leaflet.
Leaflet texts were prepared by recent Japanese
prisoners of war because they were thought
to be the best choice "to appeal to their
compatriots".In preparation for dropping an
atomic bomb on Hiroshima, the Oppenheimer-led
Scientific Panel of the Interim Committee
decided against a demonstration bomb and against
a special leaflet warning.
Those decisions were implemented because of
the uncertainty of a successful detonation
and also because of the wish to maximize shock
in the leadership.
No warning was given to Hiroshima that a new
and much more destructive bomb was going to
be dropped.
Various sources gave conflicting information
about when the last leaflets were dropped
on Hiroshima prior to the atomic bomb.
Robert Jay Lifton wrote that it was July 27,
and Theodore H. McNelly wrote that it was
July 30.
The USAAF history noted that eleven cities
were targeted with leaflets on July 27, but
Hiroshima was not one of them, and there were
no leaflet sorties on July 30.
Leaflet sorties were undertaken on August
1 and August 4.
Hiroshima may have been leafleted in late
July or early August, as survivor accounts
talk about a delivery of leaflets a few days
before the atomic bomb was dropped.
Three versions were printed of a leaflet listing
11 or 12 cities targeted for firebombing;
a total of 33 cities listed.
With the text of this leaflet reading in Japanese
"...we cannot promise that only these cities
will be among those attacked..."
Hiroshima was not listed.
=== Consultation with Britain and Canada ===
In 1943, The United States and the United
Kingdom signed the Quebec Agreement, which
stipulated that nuclear weapons would not
be used against another country without mutual
consent.
Stimson therefore had to obtain British permission.
A meeting of the Combined Policy Committee
was held at the Pentagon on July 4, 1945.
Field Marshal Sir Henry Maitland Wilson announced
that the British government concurred with
the use of nuclear weapons against Japan,
which would be officially recorded as a decision
of the Combined Policy Committee.
As the release of information to third parties
was also controlled by the Quebec Agreement,
discussion then turned to what scientific
details would be revealed in the press announcement
of the bombing.
The meeting also considered what Truman could
reveal to Joseph Stalin, the leader of the
Soviet Union, at the upcoming Potsdam Conference,
as this also required British concurrence.
Orders for the attack were issued to General
Carl Spaatz on July 25 under the signature
of General Thomas T. Handy, the acting Chief
of Staff, since Marshall was at the Potsdam
Conference with Truman.
It read:
The 509th Composite Group, 20th Air Force
will deliver its first special bomb as soon
as weather will permit visual bombing after
about 3 August 1945 on one of the targets:
Hiroshima, Kokura, Niigata and Nagasaki.
To carry military and civilian scientific
personnel from the War Department to observe
and record the effects of the explosion of
the bomb, additional aircraft will accompany
the airplane carrying the bomb.
The observing planes will stay several miles
distant from the point of impact of the bomb.
Additional bombs will be delivered on the
above targets as soon as made ready by the
project staff.
Further instructions will be issued concerning
targets other than those listed above.
That day, Truman noted in his diary that:This
weapon is to be used against Japan between
now and August 10th.
I have told the Sec. of War, Mr. Stimson,
to use it so that military objectives and
soldiers and sailors are the target and not
women and children.
Even if the Japs are savages, ruthless, merciless
and fanatic, we as the leader of the world
for the common welfare cannot drop that terrible
bomb on the old capital [Kyoto] or the new
[Tokyo].
He and I are in accord.
The target will be a purely military one.
=== Potsdam Declaration ===
The July 16 success of the Trinity Test in
the New Mexico desert exceeded expectations.
On July 26, Allied leaders issued the Potsdam
Declaration, which outlined the terms of surrender
for Japan.
The declaration was presented as an ultimatum
and stated that without a surrender, the Allies
would attack Japan, resulting in "the inevitable
and complete destruction of the Japanese armed
forces and just as inevitably the utter devastation
of the Japanese homeland".
The atomic bomb was not mentioned in the communiqué.On
July 28, Japanese papers reported that the
declaration had been rejected by the Japanese
government.
That afternoon, Prime Minister Suzuki Kantarō
declared at a press conference that the Potsdam
Declaration was no more than a rehash (yakinaoshi)
of the Cairo Declaration and that the government
intended to ignore it (mokusatsu, "kill by
silence").
The statement was taken by both Japanese and
foreign papers as a clear rejection of the
declaration.
Emperor Hirohito, who was waiting for a Soviet
reply to non-committal Japanese peace feelers,
made no move to change the government position.
Japan's willingness to surrender remained
conditional on the preservation of the kokutai
(Imperial institution and national polity),
assumption by the Imperial Headquarters of
responsibility for disarmament and demobilization,
no occupation of the Japanese Home Islands,
Korea or Formosa, and delegation of the punishment
of war criminals to the Japanese government.At
Potsdam, Truman agreed to a request from Winston
Churchill that Britain be represented when
the atomic bomb was dropped.
William Penney and Group Captain Leonard Cheshire
were sent to Tinian, but found that LeMay
would not let them accompany the mission.
All they could do was send a strongly worded
signal to Wilson.
=== Bombs ===
The Little Boy bomb, except for the uranium
payload, was ready at the beginning of May
1945.
There were two uranium-235 components, a hollow
cylindrical projectile and a cylindrical target
insert.
The projectile was completed on June 15, and
the target insert on July 24.
The projectile and eight bomb pre-assemblies
(partly assembled bombs without the powder
charge and fissile components) left Hunters
Point Naval Shipyard, California, on July
16 aboard the cruiser USS Indianapolis, and
arrived on Tinian on July 26.
The target insert followed by air on July
30, accompanied by Commander Francis Birch
from Project Alberta.
Responding to concerns expressed by the 509th
Composite Group about the possibility of a
B-29 crashing on takeoff, Birch had modified
the Little Boy design to incorporate a removable
breech plug that would permit the bomb to
be armed in flight.The first plutonium core,
along with its polonium-beryllium urchin initiator,
was transported in the custody of Project
Alberta courier Raemer Schreiber in a magnesium
field carrying case designed for the purpose
by Philip Morrison.
Magnesium was chosen because it does not act
as a tamper.
The core departed from Kirtland Army Air Field
on a C-54 transport aircraft of the 509th
Composite Group's 320th Troop Carrier Squadron
on July 26, and arrived at North Field July
28.
Three Fat Man high-explosive pre-assemblies,
designated F31, F32, and F33, were picked
up at Kirtland on July 28 by three B-29s,
two from the 393d Bombardment Squadron plus
one from the 216th Army Air Force Base Unit,
and transported to North Field, arriving on
August 2.
== Hiroshima ==
=== 
Hiroshima during World War II ===
At the time of its bombing, Hiroshima was
a city of industrial and military significance.
A number of military units were located nearby,
the most important of which was the headquarters
of Field Marshal Shunroku Hata's Second General
Army, which commanded the defense of all of
southern Japan, and was located in Hiroshima
Castle.
Hata's command consisted of some 400,000 men,
most of whom were on Kyushu where an Allied
invasion was correctly anticipated.
Also present in Hiroshima were the headquarters
of the 59th Army, the 5th Division and the
224th Division, a recently formed mobile unit.
The city was defended by five batteries of
7-cm and 8-cm (2.8 and 3.1 inch) anti-aircraft
guns of the 3rd Anti-Aircraft Division, including
units from the 121st and 122nd Anti-Aircraft
Regiments and the 22nd and 45th Separate Anti-Aircraft
Battalions.
In total, an estimated 40,000 Japanese military
personnel were stationed in the city.Hiroshima
was a supply and logistics base for the Japanese
military.
The city was a communications center, a key
port for shipping, and an assembly area for
troops.
It was a beehive of war industry, manufacturing
parts for planes and boats, for bombs, rifles,
and handguns.
The center of the city contained several reinforced
concrete buildings and lighter structures.
Outside the center, the area was congested
by a dense collection of small timber workshops
set among Japanese houses.
A few larger industrial plants lay near the
outskirts of the city.
The houses were constructed of timber with
tile roofs, and many of the industrial buildings
were also built around timber frames.
The city as a whole was highly susceptible
to fire damage.
It was the second largest city in Japan after
Kyoto that was still undamaged by air raids,
primarily because it lacked the aircraft manufacturing
industry that was the XXI Bomber Command's
priority target.
On July 3, the Joint Chiefs of Staff placed
it off limits to bombers, along with Kokura,
Niigata and Kyoto.The population of Hiroshima
had reached a peak of over 381,000 earlier
in the war but prior to the atomic bombing,
the population had steadily decreased because
of a systematic evacuation ordered by the
Japanese government.
At the time of the attack, the population
was approximately 340,000–350,000.
Residents wondered why Hiroshima had been
spared destruction by firebombing.
Some speculated that the city was to be saved
for U.S. occupation headquarters, others thought
perhaps their relatives in Hawaii and California
had petitioned the U.S. government to avoid
bombing Hiroshima.
More realistic city officials had ordered
buildings torn down to create long, straight
firebreaks.
These continued to be expanded and extended
up to the morning of August 6, 1945.
=== Bombing of Hiroshima ===
Hiroshima was the primary target of the first
atomic bombing mission on August 6, with Kokura
and Nagasaki as alternative targets.
The 393d Bombardment Squadron B-29 Enola Gay,
named after Tibbets' mother and piloted by
Tibbets, took off from North Field, Tinian,
about six hours' flight time from Japan.
Enola Gay was accompanied by two other B-29s:
The Great Artiste, commanded by Major Charles
Sweeney, which carried instrumentation, and
a then-nameless aircraft later called Necessary
Evil, commanded by Captain George Marquardt,
which served as the photography aircraft.
After leaving Tinian, the aircraft made their
way separately to Iwo Jima to rendezvous with
Sweeney and Marquardt at 05:55 at 9,200 feet
(2,800 m), and set course for Japan.
The aircraft arrived over the target in clear
visibility at 31,060 feet (9,470 m).
Parsons, who was in command of the mission,
armed the bomb in flight to minimize the risks
during takeoff.
He had witnessed four B-29s crash and burn
at takeoff, and feared that a nuclear explosion
would occur if a B-29 crashed with an armed
Little Boy on board.
His assistant, Second Lieutenant Morris R.
Jeppson, removed the safety devices 30 minutes
before reaching the target area.
During the night of August 5–6, Japanese
early warning radar detected the approach
of numerous American aircraft headed for the
southern part of Japan.
Radar detected 65 bombers headed for Saga,
102 bound for Maebashi, 261 en route to Nishinomiya,
111 headed for Ube and 66 bound for Imabari.
An alert was given and radio broadcasting
stopped in many cities, among them Hiroshima.
The all-clear was sounded in Hiroshima at
00:05.
About an hour before the bombing, the air
raid alert was sounded again, as Straight
Flush flew over the city.
It broadcast a short message which was picked
up by Enola Gay.
It read: "Cloud cover less than 3/10th at
all altitudes.
Advice: bomb primary."
The all-clear was sounded over Hiroshima again
at 07:09.At 08:09, Tibbets started his bomb
run and handed control over to his bombardier,
Major Thomas Ferebee.
The release at 08:15 (Hiroshima time) went
as planned, and the Little Boy containing
about 64 kg (141 lb) of uranium-235 took 44.4
seconds to fall from the aircraft flying at
about 31,000 feet (9,400 m) to a detonation
height of about 1,900 feet (580 m) above the
city.
Enola Gay traveled 11.5 mi (18.5 km) before
it felt the shock waves from the blast.Due
to crosswind, the bomb missed the aiming point,
the Aioi Bridge, by approximately 800 ft (240
m) and detonated directly over Shima Surgical
Clinic.
It released the equivalent energy of 16 kilotons
of TNT (67 TJ), ± 2 kt.
The weapon was considered very inefficient,
with only 1.7% of its material fissioning.
The radius of total destruction was about
1 mile (1.6 km), with resulting fires across
4.4 square miles (11 km2).Enola Gay stayed
over the target area for two minutes and was
ten miles away when the bomb detonated.
Only Tibbets, Parsons, and Ferebee knew of
the nature of the weapon; the others on the
bomber were only told to expect a blinding
flash and given black goggles.
"It was hard to believe what we saw", Tibbets
told reporters, while Parsons said "the whole
thing was tremendous and awe-inspiring ... the
men aboard with me gasped 'My God'".
He and Tibbets compared the shockwave to "a
close burst of ack-ack fire".
=== Events on the ground ===
People on the ground reported a pika (ピカ)—a
brilliant flash of light—followed by a don
(ドン)—a loud booming sound.
Some 70,000–80,000 people, around 30% of
the population of Hiroshima at the time, were
killed by the blast and resultant firestorm,
and another 70,000 were injured.
It is estimated that as many as 20,000 Japanese
military personnel were killed.
U.S. surveys estimated that 4.7 square miles
(12 km2) of the city were destroyed.
Japanese officials determined that 69% of
Hiroshima's buildings were destroyed and another
6–7% damaged.Some of the reinforced concrete
buildings in Hiroshima had been very strongly
constructed because of the earthquake danger
in Japan, and their framework did not collapse
even though they were fairly close to the
blast center.
Since the bomb detonated in the air, the blast
was directed more downward than sideways,
which was largely responsible for the survival
of the Prefectural Industrial Promotional
Hall, now commonly known as the Genbaku (A-bomb)
dome.
This building was designed and built by the
Czech architect Jan Letzel, and was only 150
m (490 ft) from ground zero.
The ruin was named Hiroshima Peace Memorial
and was made a UNESCO World Heritage Site
in 1996 over the objections of the United
States and China, which expressed reservations
on the grounds that other Asian nations were
the ones who suffered the greatest loss of
life and property, and a focus on Japan lacked
historical perspective.
The bombing started intense fires that spread
rapidly through timber and paper homes, burning
everything in a radius of 2 kilometers (1.2
mi).
As in other Japanese cities, the firebreaks
proved ineffective.
The air raid warning had been cleared at 07:31,
and many people were outside, going about
their activities.
Eizō Nomura was the closest known survivor,
being in the basement of a reinforced concrete
building (it remained as the Rest House after
the war) only 170 meters (560 ft) from ground
zero (the hypocenter) at the time of the attack.
He died in 1982, aged 84.
Akiko Takakura was among the closest survivors
to the hypocenter of the blast.
She was in the solidly-built Bank of Hiroshima
only 300 meters (980 ft) from ground-zero
at the time of the attack.
Over 90% of the doctors and 93% of the nurses
in Hiroshima were killed or injured—most
had been in the downtown area which received
the greatest damage.
The hospitals were destroyed or heavily damaged.
Only one doctor, Terufumi Sasaki, remained
on duty at the Red Cross Hospital.
Nonetheless, by early afternoon the police
and volunteers had established evacuation
centres at hospitals, schools and tram stations,
and a morgue was established in the Asano
library.Most elements of the Japanese Second
General Army headquarters were undergoing
physical training on the grounds of Hiroshima
Castle, barely 900 yards (820 m) from the
hypocenter.
The attack killed 3,243 troops on the parade
ground.
The communications room of Chugoku Military
District Headquarters that was responsible
for issuing and lifting air raid warnings
was located in a semi-basement in the castle.
Yoshie Oka, a Hijiyama Girls High School student
who had been mobilized to serve as a communications
officer had just sent a message that the alarm
had been issued for Hiroshima and neighboring
Yamaguchi, when the bomb exploded.
She used a special phone to inform Fukuyama
Headquarters (some 100 kilometers (62 mi)
away) that "Hiroshima has been attacked by
a new type of bomb.
The city is in a state of near-total destruction."Since
Mayor Senkichi Awaya had been killed while
eating breakfast with his son and granddaughter
at the mayoral residence, Field Marshal Shunroku
Hata, who was only slightly wounded, took
over the administration of the city, and coordinated
relief efforts.
Many of his staff had been killed or fatally
wounded, including a Korean prince of the
Joseon Dynasty, Yi U, who was serving as a
lieutenant colonel in the Japanese Army.
Hata's senior surviving staff officer was
the wounded Colonel Kumao Imoto, who acted
as his chief of staff.
Soldiers from the undamaged Hiroshima Ujina
Harbor used Shinyo-class suicide motorboats,
intended to repel the American invasion, to
collect the wounded and take them down the
rivers to the military hospital at Ujina.
Trucks and trains brought in relief supplies
and evacuated survivors from the city.Twelve
American airmen were imprisoned at the Chugoku
Military Police Headquarters, about 1,300
feet (400 m) from the hypocenter of the blast.
Most died instantly, although two were reported
to have been executed by their captors, and
two prisoners badly injured by the bombing
were left next to the Aioi Bridge by the Kempei
Tai, where they were stoned to death.
Eight U.S. prisoners of war killed as part
of the medical experiments program at Kyushu
University were falsely reported by Japanese
authorities as having been killed in the atomic
blast as part of an attempted cover up.
=== Japanese realization of the bombing ===
The Tokyo control operator of the Japan Broadcasting
Corporation noticed that the Hiroshima station
had gone off the air.
He tried to re-establish his program by using
another telephone line, but it too had failed.
About 20 minutes later the Tokyo railroad
telegraph center realized that the main line
telegraph had stopped working just north of
Hiroshima.
From some small railway stops within 16 km
(10 mi) of the city came unofficial and confused
reports of a terrible explosion in Hiroshima.
All these reports were transmitted to the
headquarters of the Imperial Japanese Army
General Staff.Military bases repeatedly tried
to call the Army Control Station in Hiroshima.
The complete silence from that city puzzled
the General Staff; they knew that no large
enemy raid had occurred and that no sizable
store of explosives was in Hiroshima at that
time.
A young officer was instructed to fly immediately
to Hiroshima, to land, survey the damage,
and return to Tokyo with reliable information
for the staff.
It was felt that nothing serious had taken
place and that the explosion was just a rumor.The
staff officer went to the airport and took
off for the southwest.
After flying for about three hours, while
still nearly 160 km (100 mi) from Hiroshima,
he and his pilot saw a great cloud of smoke
from the bomb.
After circling the city to survey the damage
they landed south of the city, where the staff
officer, after reporting to Tokyo, began to
organize relief measures.
Tokyo's first indication that the city had
been destroyed by a new type of bomb came
from President Truman's announcement of the
strike, sixteen hours later.
== Events of August 7–9 ==
After the Hiroshima bombing, Truman issued
a statement announcing the use of the new
weapon.
He stated, "We may be grateful to Providence"
that the German atomic bomb project had failed,
and that the United States and its allies
had "spent two billion dollars on the greatest
scientific gamble in history—and won".
Truman then warned Japan: "If they do not
now accept our terms, they may expect a rain
of ruin from the air, the like of which has
never been seen on this earth.
Behind this air attack will follow sea and
land forces in such numbers and power as they
have not yet seen and with the fighting skill
of which they are already well aware."
This was a widely broadcast speech picked
up by Japanese news agencies.
The 50,000-watt standard wave station on Saipan,
the OWI radio station, broadcast a similar
message to Japan every 15 minutes about Hiroshima,
stating that more Japanese cities would face
a similar fate in the absence of immediate
acceptance of the terms of the Potsdam Declaration
and emphatically urged civilians to evacuate
major cities.
Radio Japan, which continued to extoll victory
for Japan by never surrendering, had informed
the Japanese of the destruction of Hiroshima
by a single bomb.
Prime Minister Suzuki felt compelled to meet
the Japanese press, to whom he reiterated
his government's commitment to ignore the
Allies' demands and fight on.Soviet Foreign
Minister Vyacheslav Molotov informed Tokyo
of the Soviet Union's unilateral abrogation
of the Soviet–Japanese Neutrality Pact on
August 5.
At two minutes past midnight on August 9,
Tokyo time, Soviet infantry, armor, and air
forces had launched the Manchurian Strategic
Offensive Operation.
Four hours later, word reached Tokyo of the
Soviet Union's official declaration of war.
The senior leadership of the Japanese Army
began preparations to impose martial law on
the nation, with the support of Minister of
War Korechika Anami, to stop anyone attempting
to make peace.On August 7, a day after Hiroshima
was destroyed, Dr. Yoshio Nishina and other
atomic physicists arrived at the city, and
carefully examined the damage.
They then went back to Tokyo and told the
cabinet that Hiroshima was indeed destroyed
by a nuclear weapon.
Admiral Soemu Toyoda, the Chief of the Naval
General Staff, estimated that no more than
one or two additional bombs could be readied,
so they decided to endure the remaining attacks,
acknowledging "there would be more destruction
but the war would go on".
American Magic codebreakers intercepted the
cabinet's messages.Purnell, Parsons, Tibbets,
Spaatz, and LeMay met on Guam that same day
to discuss what should be done next.
Since there was no indication of Japan surrendering,
they decided to proceed with dropping another
bomb.
Parsons said that Project Alberta would have
it ready by August 11, but Tibbets pointed
to weather reports indicating poor flying
conditions on that day due to a storm, and
asked if the bomb could be readied by August
9.
Parsons agreed to try to do so.
== Nagasaki ==
=== 
Nagasaki during World War II ===
The city of Nagasaki had been one of the largest
seaports in southern Japan, and was of great
wartime importance because of its wide-ranging
industrial activity, including the production
of ordnance, ships, military equipment, and
other war materials.
The four largest companies in the city were
Mitsubishi Shipyards, Electrical Shipyards,
Arms Plant, and Steel and Arms Works, which
employed about 90% of the city's labor force,
and accounted for 90% of the city's industry.
Although an important industrial city, Nagasaki
had been spared from firebombing because its
geography made it difficult to locate at night
with AN/APQ-13 radar.Unlike the other target
cities, Nagasaki had not been placed off limits
to bombers by the Joint Chiefs of Staff's
July 3 directive, and was bombed on a small
scale five times.
During one of these raids on August 1, a number
of conventional high-explosive bombs were
dropped on the city.
A few hit the shipyards and dock areas in
the southwest portion of the city, and several
hit the Mitsubishi Steel and Arms Works.
By early August, the city was defended by
the 134th Anti-Aircraft Regiment of the 4th
Anti-Aircraft Division with four batteries
of 7 cm (2.8 in) anti-aircraft guns and two
searchlight batteries.
In contrast to Hiroshima, almost all of the
buildings were of old-fashioned Japanese construction,
consisting of timber or timber-framed buildings
with timber walls (with or without plaster)
and tile roofs.
Many of the smaller industries and business
establishments were also situated in buildings
of timber or other materials not designed
to withstand explosions.
Nagasaki had been permitted to grow for many
years without conforming to any definite city
zoning plan; residences were erected adjacent
to factory buildings and to each other almost
as closely as possible throughout the entire
industrial valley.
On the day of the bombing, an estimated 263,000
people were in Nagasaki, including 240,000
Japanese residents, 10,000 Korean residents,
2,500 conscripted Korean workers, 9,000 Japanese
soldiers, 600 conscripted Chinese workers,
and 400 Allied prisoners of war in a camp
to the north of Nagasaki.
=== Bombing of Nagasaki ===
Responsibility for the timing of the second
bombing was delegated to Tibbets.
Scheduled for August 11 against Kokura, the
raid was moved earlier by two days to avoid
a five-day period of bad weather forecast
to begin on August 10.
Three bomb pre-assemblies had been transported
to Tinian, labeled F-31, F-32, and F-33 on
their exteriors.
On August 8, a dress rehearsal was conducted
off Tinian by Sweeney using Bockscar as the
drop airplane.
Assembly F-33 was expended testing the components
and F-31 was designated for the August 9 mission.
At 03:49 on the morning of August 9, 1945,
Bockscar, flown by Sweeney's crew, carried
Fat Man, with Kokura as the primary target
and Nagasaki the secondary target.
The mission plan for the second attack was
nearly identical to that of the Hiroshima
mission, with two B-29s flying an hour ahead
as weather scouts and two additional B-29s
in Sweeney's flight for instrumentation and
photographic support of the mission.
Sweeney took off with his weapon already armed
but with the electrical safety plugs still
engaged.During pre-flight inspection of Bockscar,
the flight engineer notified Sweeney that
an inoperative fuel transfer pump made it
impossible to use 640 US gallons (2,400 l;
530 imp gal) of fuel carried in a reserve
tank.
This fuel would still have to be carried all
the way to Japan and back, consuming still
more fuel.
Replacing the pump would take hours; moving
the Fat Man to another aircraft might take
just as long and was dangerous as well, as
the bomb was live.
Tibbets and Sweeney therefore elected to have
Bockscar continue the mission.This time Penney
and Cheshire were allowed to accompany the
mission, flying as observers on the third
plane, Big Stink, flown by the group's operations
officer, Major James I. Hopkins, Jr.
Observers aboard the weather planes reported
both targets clear.
When Sweeney's aircraft arrived at the assembly
point for his flight off the coast of Japan,
Big Stink failed to make the rendezvous.
According to Cheshire, Hopkins was at varying
heights including 9,000 feet (2,700 m) higher
than he should have been, and was not flying
tight circles over Yakushima as previously
agreed with Sweeney and Captain Frederick
C. Bock, who was piloting the support B-29
The Great Artiste.
Instead, Hopkins was flying 40-mile (64 km)
dogleg patterns.
Though ordered not to circle longer than fifteen
minutes, Sweeney continued to wait for Big
Stink for forty minutes.
Before leaving the rendezvous point, Sweeney
consulted Ashworth, who was in charge of the
bomb.
As commander of the aircraft, Sweeney made
the decision to proceed to the primary, the
city of Kokura.
After exceeding the original departure time
limit by nearly a half-hour, Bockscar, accompanied
by The Great Artiste, proceeded to Kokura,
thirty minutes away.
The delay at the rendezvous had resulted in
clouds and drifting smoke over Kokura from
fires started by a major firebombing raid
by 224 B-29s on nearby Yahata the previous
day.
Additionally, the Yahata Steel Works intentionally
burned coal tar, to produce black smoke.
The clouds and smoke resulted in 70% of the
area over Kokura being covered, obscuring
the aiming point.
Three bomb runs were made over the next 50
minutes, burning fuel and exposing the aircraft
repeatedly to the heavy defenses around Kokura,
but the bombardier was unable to drop visually.
By the time of the third bomb run, Japanese
anti-aircraft fire was getting close, and
Second Lieutenant Jacob Beser, who was monitoring
Japanese communications, reported activity
on the Japanese fighter direction radio bands.After
three runs over the city, and with fuel running
low because of the failed fuel pump, Bockscar
and The Great Artiste headed for their secondary
target, Nagasaki.
Fuel consumption calculations made en route
indicated that Bockscar had insufficient fuel
to reach Iwo Jima and would be forced to divert
to Okinawa, which had become entirely Allied-occupied
territory only six weeks earlier.
After initially deciding that if Nagasaki
were obscured on their arrival the crew would
carry the bomb to Okinawa and dispose of it
in the ocean if necessary, Ashworth agreed
with Sweeney's suggestion that a radar approach
would be used if the target was obscured.
At about 07:50 Japanese time, an air raid
alert was sounded in Nagasaki, but the "all
clear" signal was given at 08:30.
When only two B-29 Superfortresses were sighted
at 10:53, the Japanese apparently assumed
that the planes were only on reconnaissance
and no further alarm was given.A few minutes
later at 11:00, The Great Artiste dropped
instruments attached to three parachutes.
These instruments also contained an unsigned
letter to Professor Ryokichi Sagane, a physicist
at the University of Tokyo who studied with
three of the scientists responsible for the
atomic bomb at the University of California,
Berkeley, urging him to tell the public about
the danger involved with these weapons of
mass destruction.
The messages were found by military authorities
but not turned over to Sagane until a month
later.
In 1949, one of the authors of the letter,
Luis Alvarez, met with Sagane and signed the
letter.At 11:01, a last-minute break in the
clouds over Nagasaki allowed Bockscar's bombardier,
Captain Kermit Beahan, to visually sight the
target as ordered.
The Fat Man weapon, containing a core of about
5 kg (11 lb) of plutonium, was dropped over
the city's industrial valley.
It exploded 47 seconds later at 1,650 ± 33
ft (503 ± 10 m), above a tennis court, halfway
between the Mitsubishi Steel and Arms Works
in the south and the Nagasaki Arsenal in the
north.
This was nearly 3 km (1.9 mi) northwest of
the planned hypocenter; the blast was confined
to the Urakami Valley and a major portion
of the city was protected by the intervening
hills.
The resulting explosion released the equivalent
energy of 21 ± 2 kt (87.9 ± 8.4 TJ).
Big Stink spotted the explosion from a hundred
miles away, and flew over to observe.
Bockscar flew on to Okinawa, arriving with
only sufficient fuel for a single approach.
Sweeney tried repeatedly to contact the control
tower for landing clearance, but received
no answer.
He could see heavy air traffic landing and
taking off from Yontan Airfield.
Firing off every flare on board to alert the
field to his emergency landing, the Bockscar
came in fast, landing at 140 miles per hour
(230 km/h) instead of the normal 120 miles
per hour (190 km/h).
The number two engine died from fuel starvation
as he began the final approach.
Touching down on only three engines midway
down the landing strip, Bockscar bounced up
into the air again for about 25 feet (7.6
m) before slamming back down hard.
The heavy B-29 slewed left and towards a row
of parked B-24 bombers before the pilots managed
to regain control.
Its reversible propellers were insufficient
to slow the aircraft adequately, and with
both pilots standing on the brakes, Bockscar
made a swerving 90-degree turn at the end
of the runway to avoid running off it.
A second engine died from fuel exhaustion
before the plane came to a stop.Following
the mission, there was confusion over the
identification of the plane.
The first eyewitness account by war correspondent
William L. Laurence of The New York Times,
who accompanied the mission aboard the aircraft
piloted by Bock, reported that Sweeney was
leading the mission in The Great Artiste.
He also noted its "Victor" number as 77, which
was that of Bockscar.
Laurence had interviewed Sweeney and his crew,
and was aware that they referred to their
airplane as The Great Artiste.
Except for Enola Gay, none of the 393d's B-29s
had yet had names painted on the noses, a
fact which Laurence himself noted in his account.
Unaware of the switch in aircraft, Laurence
assumed Victor 77 was The Great Artiste, which
was in fact, Victor 89.
=== Events on the ground ===
Although the bomb was more powerful than the
one used on Hiroshima, its effects were confined
by hillsides to the narrow Urakami Valley.
Of 7,500 Japanese employees who worked inside
the Mitsubishi Munitions plant, including
"mobilized" students and regular workers,
6,200 were killed.
Some 17,000–22,000 others who worked in
other war plants and factories in the city
died as well.
Casualty estimates for immediate deaths vary
widely, ranging from 22,000 to 75,000.
At least 35,000–40,000 people were killed
and 60,000 others injured.
In the days and months following the explosion,
more people died from their injuries.
Because of the presence of undocumented foreign
workers, and a number of military personnel
in transit, there are great discrepancies
in the estimates of total deaths by the end
of 1945; a range of 39,000 to 80,000 can be
found in various studies.Unlike Hiroshima's
military death toll, only 150 Japanese soldiers
were killed instantly, including 36 from the
134th AAA Regiment of the 4th AAA Division.
At least eight Allied prisoners of war (POWs)
died from the bombing, and as many as thirteen
may have died.
The eight confirmed deaths included a British
POW, Royal Air Force Corporal Ronald Shaw,
and seven Dutch POWs.
One American POW, Joe Kieyoomia, was in Nagasaki
at the time of the bombing but survived, reportedly
having been shielded from the effects of the
bomb by the concrete walls of his cell.
There were 24 Australian POWs in Nagasaki,
all of whom survived.
The radius of total destruction was about
1 mi (1.6 km), followed by fires across the
northern portion of the city to 2 mi (3.2
km) south of the bomb.
About 58% of the Mitsubishi Arms Plant was
damaged, and about 78% of the Mitsubishi Steel
Works.
The Mitsubishi Electric Works suffered only
10% structural damage as it was on the border
of the main destruction zone.
The Nagasaki Arsenal was destroyed in the
blast.
Although many fires likewise burnt following
the bombing, in contrast to Hiroshima where
sufficient fuel density was available, no
firestorm developed in Nagasaki as the damaged
areas did not furnish enough fuel to generate
the phenomenon.
Instead, the ambient wind at the time pushed
the fire spread along the valley.As in Hiroshima,
the bombing badly dislocated the city's medical
facilities.
A makeshift hospital was established at the
Shinkozen Primary School, which served as
the main medical centre.
The trains were still running, and evacuated
many victims to hospitals in nearby towns.
A medical team from a naval hospital reached
the city in the evening, and fire-fighting
brigades from the neighboring towns assisted
in fighting the fires.
Takashi Nagai was a doctor working in the
radiology department of Nagasaki Medical College
Hospital.
He received a serious injury that severed
his right temporal artery, but joined the
rest of the surviving medical staff in treating
bombing victims.
== Plans for more atomic attacks on Japan
==
Groves expected to have another "Fat Man"
atomic bomb ready for use on August 19, with
three more in September and a further three
in October(a second Little Boy bomb (using
U-235) would not be available until December
1945 ). On August 10, he sent a memorandum
to Marshall in which he wrote that "the next
bomb ... should be ready for delivery on the
first suitable weather after 17 or 18 August."
Marshall endorsed the memo with the hand-written
comment, "It is not to be released over Japan
without express authority from the President",
something Truman had requested that day.
This modified the previous order that the
target cities were to be attacked with atomic
bombs "as made ready".
There was already discussion in the War Department
about conserving the bombs then in production
for Operation Downfall, and Marshall suggested
to Stimson that the remaining cities on the
target list be spared attack with atomic bombs.Two
more Fat Man assemblies were readied, and
scheduled to leave Kirtland Field for Tinian
on August 11 and 14, and Tibbets was ordered
by LeMay to return to Albuquerque, New Mexico,
to collect them.
At Los Alamos, technicians worked 24 hours
straight to cast another plutonium core.
Although cast, it still needed to be pressed
and coated, which would take until August
16.
Therefore, it could have been ready for use
on August 19.
Unable to reach Marshall, Groves ordered on
his own authority on August 13 that the core
should not be shipped.
== Surrender of Japan and subsequent occupation
==
Until August 9, Japan's war council still
insisted on its four conditions for surrender.
The full cabinet met on 14:30 on August 9,
and spent most of the day debating surrender.
Anami conceded that victory was unlikely,
but argued in favour of continuing the war
nonetheless.
The meeting ended at 17:30, with no decision
having been reached.
Suzuki went to the palace to report on the
outcome of meeting, where he met with Kōichi
Kido, the Lord Keeper of the Privy Seal of
Japan.
Kido informed him that the emperor had agreed
to hold an imperial conference, and gave a
strong indication that the emperor would consent
to surrender on condition that kokutai be
preserved.
A second cabinet meeting was held at 18:00.
Only four ministers supported Anami's position
of adhering to the four conditions, but since
cabinet decisions had to be unanimous, no
decision was reached before it ended at 22:00.Calling
an imperial conference required the signatures
of the prime minister and the two service
chiefs, but the Chief Cabinet Secretary Hisatsune
Sakomizu had already obtained signatures from
Toyoda and General Yoshijirō Umezu in advance,
and he reneged on his promise to inform them
if a meeting was to be held.
The meeting commenced at 23:50.
No consensus had emerged by 02:00 on August
10, but the emperor gave his "sacred decision",
authorizing the Foreign Minister, Shigenori
Tōgō, to notify the Allies that Japan would
accept their terms on one condition, that
the declaration "does not comprise any demand
which prejudices the prerogatives of His Majesty
as a Sovereign ruler."On August 12, the Emperor
informed the imperial family of his decision
to surrender.
One of his uncles, Prince Asaka, then asked
whether the war would be continued if the
kokutai could not be preserved.
Hirohito simply replied, "Of course."
As the Allied terms seemed to leave intact
the principle of the preservation of the Throne,
Hirohito recorded on August 14 his capitulation
announcement which was broadcast to the Japanese
nation the next day despite a short rebellion
by militarists opposed to the surrender.In
his declaration, Hirohito referred to the
atomic bombings, and did not explicitly mention
the Soviets as a factor for surrender:
Despite the best that has been done by every
one—the gallant fighting of military and
naval forces, the diligence and assiduity
of Our servants of the State and the devoted
service of Our one hundred million people,
the war situation has developed not necessarily
to Japan's advantage, while the general trends
of the world have all turned against her interest.
Moreover, the enemy now possesses a new and
terrible weapon with the power to destroy
many innocent lives and do incalculable damage.
Should we continue to fight, not only would
it result in an ultimate collapse and obliteration
of the Japanese nation, but also it would
lead to the total extinction of human civilization.
Such being the case, how are we to save the
millions of our subjects, or to atone ourselves
before the hallowed spirits of our imperial
ancestors?
This is the reason why we have ordered the
acceptance of the provisions of the joint
declaration of the powers.
In his "Rescript to the Soldiers and Sailors"
delivered on August 17, however, he stressed
the impact of the Soviet invasion on his decision
to surrender.
== Reportage ==
On August 10, 1945, the day after the Nagasaki
bombing, Yōsuke Yamahata, correspondent Higashi,
and artist Yamada arrived in the city with
orders to record the destruction for maximum
propaganda purposes, Yamahata took scores
of photographs, and on August 21, they appeared
in Mainichi Shimbun, a popular Japanese newspaper.
Leslie Nakashima filed the first personal
account of the scene to appear in American
newspapers.
A version of his August 27 UPI article appeared
in The New York Times on August 31.Wilfred
Burchett was the first western journalist
to visit Hiroshima after the bombing, arriving
alone by train from Tokyo on September 2.
His Morse code dispatch, "The Atomic Plague",
was printed by the Daily Express newspaper
in London on September 5, 1945.
Nakashima's and Burchett's reports were the
first public reports to mention the effects
of radiation and nuclear fallout—radiation
burns and radiation poisoning.
Burchett's reporting was unpopular with the
U.S. military, who accused Burchett of being
under the sway of Japanese propaganda, and
suppressed a supporting story submitted by
George Weller of the Chicago Daily News.
Laurence dismissed the reports on radiation
sickness as Japanese efforts to undermine
American morale, ignoring his own account
published one week earlier.A member of the
U.S. Strategic Bombing Survey, Lieutenant
Daniel McGovern, used a film crew to document
the effects of the bombings in early 1946.
The film crew shot 90,000 ft (27,000 m) of
film, resulting in a three-hour documentary
titled The Effects of the Atomic Bombs Against
Hiroshima and Nagasaki.
The documentary included images from hospitals
showing the human effects of the bomb; it
showed burned-out buildings and cars, and
rows of skulls and bones on the ground.
It was classified "secret" for the next 22
years.
Motion picture company Nippon Eigasha started
sending cameramen to Nagasaki and Hiroshima
in September 1945.
On October 24, 1945, a U.S. military policeman
stopped a Nippon Eigasha cameraman from continuing
to film in Nagasaki.
All Nippon Eigasha's reels were confiscated
by the American authorities, but they were
requested by the Japanese government, and
declassified.
The public release of film footage of the
city post-attack, and some research about
the effects of the attack, was restricted
during the occupation of Japan, but the Hiroshima-based
magazine, Chugoku Bunka, in its first issue
published on March 10, 1946, devoted itself
to detailing the damage from the bombing.
The book Hiroshima, written by Pulitzer Prize
winner John Hersey, which was originally published
in article form in the popular magazine The
New Yorker, on August 31, 1946, is reported
to have reached Tokyo in English by January
1947, and the translated version was released
in Japan in 1949.
It narrated the stories of the lives of six
bomb survivors from immediately prior to,
and months after, the dropping of the Little
Boy bomb.
Beginning in 1974, a compilation of drawings
and artwork made by the survivors of the bombings
began to be compiled, with completion in 1977,
and under both book and exhibition format,
it was titled The Unforgettable Fire.The bombing
amazed Otto Hahn and other German atomic scientists,
whom the British held at Farm Hall in Operation
Epsilon.
Hahn stated that he had not believed an atomic
weapon "would be possible for another twenty
years"; Werner Heisenberg did not believe
the news at first.
Carl Friedrich von Weizsäcker said "I think
it's dreadful of the Americans to have done
it.
I think it is madness on their part", but
Heisenberg replied, "One could equally well
say 'That's the quickest way of ending the
war'".
Hahn was grateful that the German project
had not succeeded in developing "such an inhumane
weapon"; Karl Wirtz observed that even if
it had, "we would have obliterated London
but would still not have conquered the world,
and then they would have dropped them on us".Hahn
told the others, "Once I wanted to suggest
that all uranium should be sunk to the bottom
of the ocean".
The Vatican agreed; L'Osservatore Romano expressed
regret that the bomb's inventors did not destroy
the weapon for the benefit of humanity.
Rev. Cuthbert Thicknesse, the Dean of St Albans,
prohibited using St Albans Abbey for a thanksgiving
service for the war's end, calling the use
of atomic weapons "an act of wholesale, indiscriminate
massacre".
Nonetheless, news of the atomic bombing was
greeted enthusiastically in the U.S.; a poll
in Fortune magazine in late 1945 showed a
significant minority of Americans (23%) wishing
that more atomic bombs could have been dropped
on Japan.
The initial positive response was supported
by the imagery presented to the public (mainly
the powerful images of the mushroom cloud).
During this time in America, it was a common
practice for editors to keep graphic images
of death out of films, magazines, and newspapers.
== Post-attack casualties ==
Frequent estimates are that 140,000 people
in Hiroshima (39% of the population) and 70,000
people in Nagasaki (28% of the population)
died in 1945, though the number which died
immediately as a result of exposure to the
blast, heat, or due to radiation, is unknown.
One Atomic Bomb Casualty Commission report
discusses 6,882 people examined in Hiroshima,
and 6,621 people examined in Nagasaki, who
were largely within 2000 meters from the hypocenter,
who suffered injuries from the blast and heat
but died from complications frequently compounded
by acute radiation syndrome (ARS), all within
about 20–30 days.
The most well known of these was Midori Naka,
some 650 meters from the hypocenter at Hiroshima,
who would travel to Tokyo and then with her
death on August 24, 1945 was to be the first
death officially certified as a result of
radiation poisoning, or as it was referred
to by many, "Atomic bomb disease".
It was unappreciated at the time but the average
radiation dose that will kill approximately
50% of adults, the LD50, was approximately
halved, that is, smaller doses were made more
lethal, when the individual experienced concurrent
blast or burn polytraumatic injuries.
Conventional skin injuries that cover a large
area frequently result in bacterial infection;
the risk of sepsis and death is increased
when a usually non-lethal radiation dose moderately
suppresses the white blood cell count.In the
spring of 1948, the Atomic Bomb Casualty Commission
(ABCC) was established in accordance with
a presidential directive from Truman to the
National Academy of Sciences–National Research
Council to conduct investigations of the late
effects of radiation among the survivors in
Hiroshima and Nagasaki.
In 1956, the ABCC published The Effect of
Exposure to the Atomic Bombs on Pregnancy
Termination in Hiroshima and Nagasaki.
The ABCC became the Radiation Effects Research
Foundation (RERF), on April 1, 1975.
A binational organization run by both the
United States and Japan, the RERF is still
in operation today.
=== Cancer increases ===
Cancers do not immediately emerge after exposure
to radiation; instead, radiation-induced cancer
has a minimum latency period of some 5+ years
and Leukemia some 2+ which peaks around 6–8
years later.
Dr Jarrett Foley published the first major
reports on the significant increased incidence
of the latter among survivors.
Almost all cases of leukemia over the following
50 years were in people exposed to more than
1Gy.
In a strictly dependent manner dependent on
their distance from the hypocenter, in the
1987 Life Span Study, conducted by the Radiation
Effects Research Foundation, a statistical
excess of 507 cancers, of undefined lethality,
were observed in 79,972 hibakusha who had
still been living between 1958–1987 and
who took part in the study.
As the epidemiology study continues with time,
the RERF estimates that, from 1950 to 2000,
46% of leukemia deaths which may include Sadako
Sasaki and 11% of solid cancers of unspecificed
lethality were likely due to radiation from
the bombs or some other post-attack city effects,
with the statistical excess being 200 leukemia
deaths and 1,700 solid cancers of undeclared
lethality.
Both of these statistics being derived from
the observation of approximately half of the
total survivors, strictly those who took part
in the study.
=== Birth defect investigations ===
While during the preimplantation period, that
is 1–10 days following conception, interuterine
radiation exposure of "at least 0.2 Gy" can
cause complications of implantation and death
of the human embryo.
The number of miscarriages caused by the radiation
from the bombings, during this radiosensitive
period, is not known.
One of the early studies conducted by the
ABCC was on the outcome of pregnancies occurring
in Hiroshima and Nagasaki, and in a control
city, Kure, located 18 mi (29 km) south of
Hiroshima, to discern the conditions and outcomes
related to radiation exposure.
James V. Neel led the study which found that
the overall number of birth defects was not
significantly higher among the children of
survivors who were pregnant at the time of
the bombings.
He also studied the longevity of the children
who survived the bombings of Hiroshima and
Nagasaki, reporting that between 90 and 95
percent were still living 50 years later.While
The National Academy of Sciences raised the
possibility that Neel's procedure did not
filter the Kure population for possible radiation
exposure which could bias the results.
Overall, a statistically insignificant increase
in birth defects occurred directly after the
bombings of Nagasaki and Hiroshima when the
cities were taken as wholes, in terms of distance
from the hypocenters however, Neel and others
noted that in approximately 50 humans who
were of an early gestational age at the time
of the bombing and who were all within about
1 kilometre (0.62 mi) from the hypocenter,
an increase in microencephaly and anencephaly
was observed upon birth, with the incidence
of these two particular malformations being
nearly 3 times what was to be expected when
compared to the control group in Kure, were
approximately 20 cases were observed in a
similar sample size.In 1985, Johns Hopkins
University geneticist James F. Crow examined
Neel's research and confirmed that the number
of birth defects was not significantly higher
in Hiroshima and Nagasaki.
Many members of the ABCC and its successor
Radiation Effects Research Foundation (RERF)
were still looking for possible birth defects
among the survivors decades later, but found
no evidence that they were significantly common
among the survivors, or inherited in the children
of survivors.
=== Investigations into brain development
===
Despite the small sample size of 1,600 to
1,800 persons who came forth as prenatally
exposed at the time of the bombings, that
were both within a close proximity to the
two hypocenters, to survive the in utero absorption
of a substantial dose of radiation and then
the malnourished post-attack environment,
data from this cohort does support the increased
risk of severe mental retardation (SMR), that
was observed in some 30 individuals, with
SMR being a common outcome of the aforementioned
microencephaly.
While a lack of statistical data, with just
30 individuals out of 1,800, prevents a definitive
determination of a threshold point, the data
collected suggests a threshold interuterine
or fetal dose for SMR, at the most radiosensitive
period of cognitive development, when there
is the largest number of undifferentiated
neural cells(8 to 15 weeks post-conception)
to begin at a threshold dose of approximately
"0.09" to "0.15" Gy, with the risk then linearly
increasing to a 43% rate of SMR when exposed
to a fetal dose of 1 Gy at any point during
these weeks of rapid Neurogenesis.However
either side of this radiosensitive age, none
of the prenatally exposed to the bombings
at an age less than 8 weeks, that is prior
to synaptogenesis or at a gestational age
more than 26 weeks "were observed to be mentally
retarded", with the condition therefore being
isolated to those solely of 8–26 weeks of
age and who absorbed more than approximately
"0.09" to "0.15" Gy of prompt radiation energy.Examination
of the prenatally exposed in terms of IQ performance
and school records, determined the beginning
of a statistically significant reduction in
both, when exposed to greater than 0.1 to
0.5 Gray, during the same gestational period
of 8–25 weeks.
However outside this period, at less than
8 weeks and greater than 26 after conception,
"there is no evidence of a radiation-related
effect on scholastic performance."The reporting
of doses in terms of absorbed energy in units
of (Gy and rad) rather than the use of the
biologically significant, biologically weighted
Sievert, in both the SMR and cognitive performance
data is typical.
The reported threshold dose variance between
the two cities, is suggested to be a manifestation
of the difference between X-ray and neutron
absorption, with Little Boy emitting substantially
more neutron flux, whereas the Baratol that
surrounded the core of Fat Man, filtered or
shifted the absorbed neutron-radiation profile,
so that the dose of radiation energy received
in Nagasaki, is mostly that from exposure
to x-rays/gamma rays, in contrast to the environment
within 1500 meters of the hypocenter at Hiroshima,
were instead the in-utero dose more depended
on the absorption of neutrons, which have
a higher biological effect per unit of energy
absorbed.
From the Radiation dose reconstruction work,
which were also informed by the 1962 BREN
Tower-Japanese city analog, the estimated
dosimetry at Hiroshima still has the largest
uncertainty as the Little Boy-bomb design
was never tested before deployment or afterward,
therefore the estimated radiation profile
absorbed by individuals at Hiroshima had required
greater reliance on calculations than the
Japanese soil, concrete and roof-tile measurements
which began to reach accurate levels and thereby
inform researchers, in the 1990s.Many other
investigations into cognitive outcomes, such
as Schizophrenia as a result of prenatal exposure,
have been conducted with "no statistically
significant linear relationship seen", there
is a suggestion that in the most extremely
exposed, those who survived within a kilometer
or so of the hypocenters, a trend emerges
akin to that seen in SMR, though the sample
size is too small to determine with any significance.
== Hibakusha ==
The survivors of the bombings are called hibakusha
(被爆者, Japanese pronunciation: [çibakɯ̥ɕa]),
a Japanese word that literally translates
to "explosion-affected people".
The Japanese government has recognized about
650,000 people as hibakusha.
As of March 31, 2018, 154,859 were still alive,
mostly in Japan.
The government of Japan recognizes about 1%
of these as having illnesses caused by radiation.
The memorials in Hiroshima and Nagasaki contain
lists of the names of the hibakusha who are
known to have died since the bombings.
Updated annually on the anniversaries of the
bombings, as of August 2018, the memorials
record the names of almost 495,000 hibakusha;
314,118 in Hiroshima and 179,226 in Nagasaki.If
they discuss their background, Hibakusha and
their children were (and still are) victims
of fear based discrimination and exclusion
when it comes to prospects of marriage or
work due to public ignorance about the consequences
of radiation sickness or that the low doses
that the majority received were less than
a routine diagnostic x-ray, much of the public
however persist with the belief that the Hibakusha
carry some hereditary or even contagious disease.
This is despite the fact that no statistically
demonstrable increase of birth defects/congenital
malformations was found among the later conceived
children born to survivors of the nuclear
weapons used at Hiroshima and Nagasaki, or
indeed has been found in the later conceived
children of cancer survivors who had previously
received radiotherapy.
The surviving women of Hiroshima and Nagasaki,
that could conceive, who were exposed to substantial
amounts of radiation, went on and had children
with no higher incidence of abnormalities/birth
defects than the rate which is observed in
the Japanese average.
A study of the long-term psychological effects
of the bombings on the survivors found that
even 17–20 years after the bombings had
occurred survivors showed a higher prevalence
of anxiety and somatization symptoms.
=== Double survivors ===
Perhaps as many as 200 people from Hiroshima
sought refuge in Nagasaki.
The 2006 documentary Twice Survived: The Doubly
Atomic Bombed of Hiroshima and Nagasaki documented
165 nijū hibakusha (lit.
double explosion-affected people), nine of
whom claimed to be in the blast zone in both
cities.
On March 24, 2009, the Japanese government
officially recognized Tsutomu Yamaguchi as
a double hibakusha.
He was confirmed to be 3 km (1.9 mi) from
ground zero in Hiroshima on a business trip
when the bomb was detonated.
He was seriously burnt on his left side and
spent the night in Hiroshima.
He arrived at his home city of Nagasaki on
August 8, the day before the bombing, and
he was exposed to residual radiation while
searching for his relatives.
He was the first officially recognized survivor
of both bombings.
He died on January 4, 2010, at the age of
93, after a battle with stomach cancer.
=== Korean survivors ===
During the war, Japan brought as many as 670,000
Korean conscripts to Japan to work as forced
labor.
About 5,000–8,000 Koreans were killed in
Hiroshima and another 1,500–2,000 died in
Nagasaki.
For many years, Korean survivors had a difficult
time fighting for the same recognition as
Hibakusha as afforded to all Japanese survivors,
a situation which resulted in the denial of
the free health benefits to them in Japan.
Most issues were eventually addressed in 2008
through lawsuits.
== Memorials ==
Hiroshima was subsequently struck by Typhoon
Ida on September 17, 1945.
More than half the bridges were destroyed,
and the roads and railroads were damaged,
further devastating the city.
The population increased from 83,000 soon
after the bombing to 146,000 in February 1946.
The city was rebuilt after the war, with help
from the national government through the Hiroshima
Peace Memorial City Construction Law passed
in 1949.
It provided financial assistance for reconstruction,
along with land donated that was previously
owned by the national government and used
for military purposes.
In 1949, a design was selected for the Hiroshima
Peace Memorial Park.
Hiroshima Prefectural Industrial Promotion
Hall, the closest surviving building to the
location of the bomb's detonation, was designated
the Hiroshima Peace Memorial.
The Hiroshima Peace Memorial Museum was opened
in 1955 in the Peace Park.
Hiroshima also contains a Peace Pagoda, built
in 1966 by Nipponzan-Myōhōji.
Nagasaki was also rebuilt after the war, but
was dramatically changed in the process.
The pace of reconstruction was initially slow,
and the first simple emergency dwellings were
not provided until 1946.
The focus on redevelopment was the replacement
of war industries with foreign trade, shipbuilding
and fishing.
This was formally declared when the Nagasaki
International Culture City Reconstruction
Law was passed in May 1949.
New temples were built, as well as new churches
owing to an increase in the presence of Christianity.
Some of the rubble was left as a memorial,
such as a torii at Sannō Shrine, and an arch
near ground zero.
New structures were also raised as memorials,
such as the Nagasaki Atomic Bomb Museum, which
was opened in the mid-1990s.
== Debate over bombings ==
The role of the bombings in Japan's surrender,
and the ethical, legal, and military controversies
surrounding the United States' justification
for them have been the subject of scholarly
and popular debate.
On one hand, it has been argued that the bombings
caused the Japanese surrender, thereby preventing
casualties that an invasion of Japan would
have involved.
Stimson talked of saving one million casualties.
The naval blockade might have starved the
Japanese into submission without an invasion,
but this would also have resulted in many
more Japanese deaths.Japanese historian Tsuyoshi
Hasegawa argued that the entry of the Soviet
Union into the war against Japan "played a
much greater role than the atomic bombs in
inducing Japan to surrender because it dashed
any hope that Japan could terminate the war
through Moscow's mediation".
A view among critics of the bombings, that
was popularized by American historian Gar
Alperovitz in 1965, is the idea of atomic
diplomacy: that the United States used nuclear
weapons to intimidate the Soviet Union in
the early stages of the Cold War.
Although not accepted by mainstream historians,
this became the position in Japanese school
history textbooks.Those who oppose the bombings
give other reasons for their view, among them:
a belief that atomic bombing is fundamentally
immoral, that the bombings counted as war
crimes, and that they constituted state terrorism.
== Legacy ==
Like the way it began, the manner in which
World War II ended cast a long shadow over
international relations for decades to come.
By June 30, 1946, there were components for
only nine atomic bombs in the US arsenal,
all Fat Man devices identical to the one used
in the bombing of Nagasaki.
The nuclear weapons were handmade devices,
and a great deal of work remained to improve
their ease of assembly, safety, reliability
and storage before they were ready for production.
There were also many improvements to their
performance that had been suggested or recommended,
but that had not been possible under the pressure
of wartime development.
The Chairman of the Joint Chiefs of Staff,
Fleet Admiral William D. Leahy had decried
the use of the atomic bombs as adopting "an
ethical standard common to the barbarians
of the Dark Ages", but in October 1947, he
reported a military requirement for 400 bombs.The
American monopoly on nuclear weapons lasted
only four years before the Soviet Union detonated
an atomic bomb in September 1949.
The United States responded with the development
of the hydrogen bomb, a nuclear weapon a thousand
times as powerful as the bombs that devastated
Hiroshima and Nagasaki.
Such ordinary fission bombs would henceforth
be regarded as small tactical nuclear weapons.
By 1986, the United States had 23,317 nuclear
weapons, while the Soviet Union had 40,159.
By 2017, nine nations had nuclear weapons,
but Japan was not one of them.
Japan reluctantly signed the Treaty on the
Non-Proliferation of Nuclear Weapons in February
1970, but it still sheltered under the American
nuclear umbrella.
American nuclear weapons were stored on Okinawa,
and sometimes in Japan itself, albeit in contravention
of agreements between the two nations.
Lacking the resources to fight the Soviet
Union using conventional forces, the Western
Alliance came to depend on the use of nuclear
weapons to defend itself during the Cold War,
a policy that became known in the 1950s as
the New Look.
In the decades after Hiroshima and Nagasaki,
the United States would threaten to use its
nuclear weapons many times
