The North Korean missile test sent people on northern Japan searching for cover. Credit:AP Analysts say it could be Kim and Trump are tussling to define the parameters of any talks. Muscling up, North Korea wants the world to accept it as a nuclear state. "This is mostly a duel between Trump and Kim Jong-un, but both have left the back door open to a deal," says John Delury, a professor of international relations at Seoul's Yonsei University. He says Tillerson's comments last week that North Korea was showing pleasing "restraint", as the US and South Korea proceeded with a military drill opposed by Kim, have "boomeranged and hit him in the face". While the choice of a Japan launch was "a bolt from the blue", he says it is the unrelenting pace of North Korea's missile tests that is unnerving the world.

Japanese Prime Minister Shinzo Abe speaks to journalists after North Korea's firing of a missile over Japan on Tuesday. Credit:AP Renmin University's professor of international relations, Shi Yinhong, sees the missile trajectory over Japan's northern Hokkaido as a bluff. "He will not take action that is suicidal and will not destroy a part of Japan. But he can make a bluff to force the other side to finally accept North Korea as a nuclear state. Negotiations would then be about North Korea becoming more peaceful and having a more reasonable foreign policy," said Professor Shi, an advisor to China's State Council. A woman walks past a TV screen in Tokyo broadcasting news of North Korea's recent missile launch. Credit:AP Both analysts agree that Washington, Seoul and Beijing are in a hard situation.

South Korean parliament was told on Monday that North Korea's Punggye-ri nuclear site appears to have been prepared for a nuclear test. Japanese Air Self-Defence Force officer demonstrates the PAC-3 surface to air interceptors at the US Yokota Air Base in Fussa, Japan. Credit:AP "This is a very difficult diplomatic situation for China," said Professor Shi. He said the threat of military action talked up by Trump over the past three months has failed as a strategy. "No-one has any plausible or convincing solution ... China, under US pressure, has used up almost all of its leverage, up to cutting oil supply, yet there is no indication that North Korea has changed track. On the other hand, North Korea is becoming more and more hateful against China."

Professor Delury says North Korea's hyperbolic statements have left open that it could negotiate - but in the context of the US ending its "hostility". As for what next, he says in Washington there is a view "this could be Kim's last little spasm because he is worried about sanctions hitting". Washington will wait, he says. "The idea is Kim Jong-un will come to us [the US] ... But from Kim's perspective, he is doing the same thing. If there are negotiations it's because you guys [the Americans] want it more than me. His country will bear the sanctions." In South Korea, the new liberal President Moon Jae-in, who had pledged to open the door to dialogue with North Korea and revive inter-Korean exchanges and trade, is instead falling into the trap of his predecessors of threatening a tougher line at each rebuff from Pyongyang, Delury says.

Loading This is playing into North Korea's game. "It is very reactive now."