The recent high-profile spat with the US over the Hollywood film "The Interview" painted North Korea's enigmatic young leader Kim Jong-un as impetuous.
The film told the story of a fictional plot to assassinate Kim Jong-un. Hackers broke into film company Sony's computers, and weeks later threatened to target any cinema which screened the film.
An FBI investigation concluded that North Korea was to blame for the cyber attack. North Korea responded angrily, with Kim Jong-un calling President Obama a "monkey".
What do we know about his ambitions? Four insiders offer their insight into what Kim Jong-un wants.
'Survival': Foreign journalist Jean Lee
Jean Lee was born in America to South Korean parents and grew up hearing stories about Korean families separated by the war in 1953. A few years ago, she became the first foreign journalist to open a bureau inside North Korea.
She was in the crowd when Kim Jong-un was first introduced to the Korean people at a military parade, and says he has had to work hard to establish his own power base.
"When he came out there was just a complete sense of shock and awe among the people at the plaza. They had never seen a picture of him. They had only really known of his existence, officially, a few weeks earlier.
"It was quite a shock to see somebody so young who was being groomed to be the next leader. He was not the oldest son, so wasn't the obvious shoo-in. There's clearly something about him, ambition, perhaps a kind of ruthlessness, some qualities that his father saw in him that he thought would carry this country into the next generation."
The world saw that ruthlessness a year ago, when he ordered the execution of his uncle for allegedly trying to overthrow the state. And the regime is known to use violence to quash dissent among ordinary people too.
But Jean Lee says it would be a mistake to think Kim Jong-un maintains control only through fear:
"One of the things that I've seen on the ground over the past couple of years is all the construction of these skating rinks. There's actually a skateboard park, the ski resort of course that opened last year, massive projects. I see all of this as an investment that they're making in their future. He is a young man. If he is going to win the support of the future generations of North Koreans who are going to be his power base, he's got to find a way to win their loyalty and this is part of that."
'A stronger economy': Businessman Geoffrey See
Geoffrey See is a Singaporean who has been travelling back and forth to North Korea for the past seven years, working with young entrepreneurs. He says North Koreans are now thinking more innovatively about the economy:
"About six years ago when we first started our programme, our counterparts would often start off with a very long spiel about socialism and how this is the system they have and they are never going to change it.
"In recent years instead of saying that, people talk about... trying to bring in what's best from overseas, and try to adjust it to fit into the system. So I think that's a very interesting change in terms of thinking."
Where this new investment is being targeted is also interesting.
"If you look at the economic zones that North Korea was investing in, one of the key areas is Wonsan. So this is an economic zone on the east coast of North Korea. It faces Japan and it borders South Korea. So it is kind of almost the furthest location you can have from China. So we believe that it's part of this broader aim to balance off Chinese economic influence in North Korea."
Kim Jong-un has also been making overtures to Russian President Putin. Two years ago, Russia wrote off 90% of North Korea's debt. But Geoffrey See says there aren't many foreign investors willing to engage with the country's idiosyncratic business environment:
"We would email the North Koreans two, three, four times and we [wouldn't] get a response, and we used to get very worried about it. We wondered if they are reading our messages, if things are moving ahead.
"We would go in like three months later from the first set of emails. When we meet with them we ask them, 'Did you receive our emails?' The response is always like, 'Oh, you are coming in three months' time, we didn't feel the need to send a response because we can just chat when you're back in here'."
'The big prize: reunification': Supporter Kim Myong Chol
Kim Myong Chol was born and lives in Japan, but is ethnically Korean.
He has been to North Korea more than 20 times in the last 40 years, and says he has met representatives of the country's elite as well as, in his words, the two Kims - Kim Jong-un's father and grandfather. He hasn't met the third Kim yet, but praises his "guts, determination and intelligence".
Some describe Kim Myong Chol as an unofficial spokesman for the leader.
"What makes him different from the two Kims," he argues, "is that he will succeed in getting what he wants. The reunification of Korea, without foreign interference. Eventually the US will leave Korea and the Korean peninsula will be re-unified.
"[The US will] realise the futility, the senselessness of American military presence in Korea. North Korea [will] become too strong for America. We have now nuclear weapons, we have intercontinental ballistic missiles, we have hydrogen bomb.
"We are victims of American aggression. North Korea is a most sanctioned country. Brutalised, criminalised, isolated by America."
He insists Kim Jong-un's unpredictable behaviour is part of his strategy to fight back:
"North Korea is a very small country. The USA is a big country with nuclear weapons. How to defeat the enemy? Outsmart them. That's the only way North Korea can survive, outsmart America."
'Friendly neighbours': China analyst Yanmei Xi
Yanmei Xie is senior China analyst for the International Crisis Group in Beijing.
She argues that Kim Jong-un can do little without China's support.
"North Korea relies on China for survival. If China cut the fuel supply across the Yarlu River which is between North Korea and China, then the regime... will collapse in a matter of weeks. So Beijing plays a very crucial and vital role in the Korean Peninsula."
And when North Korea does something that China doesn't like, its punishment is swift and exact:
"When there were reports and intelligence saying North Korea could be on the brink of a fourth nuclear test, China slowed down fuel supply and food aid.
"But before it did that, China looked into the fuel supply and harvest of grain and calculated the amount of reduction in order to make sure that the reduction would not cause instability. [This] was meant to send a signal of displeasure but not to destabilise the regime or cause real pain."
This is because China also needs its neighbour: North Korea stands between China and the 28,000 US soldiers stationed in South Korea.
"North Korea used to be a military buffer for China in terms of heading off any potential advance of US armies. Now in the age of naval and air dominance of United States, a land war is not as important, but North Korea remains a political buffer in that it is a buffer between China and South Korea, which remains a US ally.
"So China shares interest of managing Kim Jong-un. But I think sometimes people confuse that with signs that China is ready to abandon the Kim Jong-un regime. But actually it's the opposite. China is... stabilising the regime... to prolong, to preserve the current status quo."
The Inquiry: What does Kim Jong-un Want? was broadcast on the BBC World Service on Tuesday 27 January, 2015.