In April, North Korea will hold a national celebration...
...to mark the birthday of the country's founding ""eternal president"" Kim Il-sung 
But 2018 will also mark another milestone
North Korea will have nuclear missiles that can reach American soil 
We'll see an alarming game of nuclear brinkmanship...
...between two of the world's most hot-headed leaders...
...Supreme Leader of North Korea, Kim Jong-un...
...and President Donald Trump
We need to be ready for anything that could happen over the next year...
...and recognise that this is a very dangerous time
As the crisis comes to a head, will 2018 bring cold war or nuclear disaster? 
Kim Jong-un is the man with a merciless character 
The world should pay attention
Communist North Korea is a secretive state of 25 million people 
Increasingly, North Koreans are fleeing the tyrannical regime 
Thae Yong-ho is one of the highest-ranking officials to defect to the West
He has unique insight into the inner workings of Mr Kim's government...
...and its nuclear ambition 
In 2018 North Korea's Kim Jong-un will test fire...
...his Inter Continental Ballistic Missile, ICBM, and its nuclear test
Kim Jong-un is really desperate to finish his goal...
...of acquiring the ability to attack America from North Korean territory 
The country is already believed to have the means to deliver nuclear warheads...
...at short and medium range
In 2017 with the world watching, Mr Kim successfully tested his long-range missile 
In 2018 he will perfect and demonstrate the ability to fit a nuclear weapon on a missile...
...and fly it all the way to the American mainland 
San Francisco and Los Angeles will be in its reach 
Kim Jong-un thinks that the ICBM and nuclear weapons...
...will be vital for his long-term survival 
The road ahead will be defined by the pugnacious personalities of Mr Kim and Mr Trump
North Korea has long been known for hurling insults at world leaders 
Mr Kim has described Mr Trump as ""a mentally deranged US dotard"" 
The President has surprised many...
...by responding to the taunts with equally provocative language
Played out in public, the war of words is unprecedented 
We will strike a merciless blow at the heart of the US
They will be met with fire and fury
The so-called ""rocket man"" is often ridiculed in the West...
...but he's proven himself to be calculating and callous 
If he thinks something really threatens his survival, he's the sort of man to do anything
He even killed his uncle and his half-brother 
It's very important that as rhetoric heats up we not allow that to tumble into a situation...
...that would create an opportunity for miscalculation
Despite the bluster and posturing...
...there is nothing to suggest either leader wants to go to war
In 2018, Donald Trump must choose between military action and diplomacy 
China is key to Mr Trump's diplomatic route
As supplier of virtually all North Korea's oil, China could curb Mr Kim's behaviour 
But so far China has been reluctant to reluctant to intervene...
...because it wants to avoid the collapse of the regime...
...which could result in a united Korea, with American troops on China's border
There is a chance, however remote, that in the year ahead, America could order...
...pre-emptive surgical strikes against North Korea's nuclear missile facilities
If we light that keg we can't assume we'll be able to dampen the fire that ensues quickly or easily
The impact of an American military intervention would have devastating consequences
North Korea has vast conventional artillery at the ready 
North Korean military officers are all trained to press their buttons if there is any attack...
...even a very limited attack by America 
North Korea would retaliate by firing missiles already positioned to hit Seoul...
...South Korea's capital
The mega city of 10 million people is only 56 kilometres from the North's border 
If North Korea chooses to attack Seoul, an ally and partner of the United States...
...the response would be devastating and overwhelming
America has 28,000 troops stationed in South Korea 
President Trump is capable of deploying cruise missiles, submarines and carriers within hours 
Kim Jong-un would reach for his stockpile of chemical...
...biological and eventually nuclear weapons 
The death toll would rise into the millions...
...until American and South Korean forces eventually overwhelm the North Korean military
But war in 2018 is unlikely 
The North Korean leader may be pushing the limits of inflammatory behaviour...
...but there is no evidence that he is irrational
Kim Jong-un knows that if he uses nuclear weapons against South Korea or America...
...then he would be the immediate subject of total destruction  
I do not think that he may initiate that kind of attack 
The appropriate response from America should not be military bravado...
...but old-fashioned cold war deterrence and containment 
Downgrade diplomatic relations with the regime
We need to make very clear that there is no way that Kim Jong-un will ever gain...
...from the use of his nuclear and missile capabilities
I think 2018, America should continue its maximum pressure policy
It can make a very negative environment for Kim Jong-un to continue his process
In the year ahead...
...America and China should increase pressure on North Korea with tougher sanctions
In 2018, the world can avoid catastrophe
