Missives met with missiles

North Korea’s latest intercontinental ballistic missile test, after a three-month lull, puts paid to optimism that pressure was finally working on Kim Jong-un and he was beginning to see sense. On the contrary, as US Defence Secretary Jim Mattis says, the highly provocative launch reveals significant technical advances since the previous test — it flew higher and for a longer duration, 54 minutes, than any of Pyongyang’s earlier ICBM tests before splashing into the Sea of Japan 1000km away. According to David Wright of the Union of Concerned Scientists, the missile, like earlier ICBM tests, had a “lofted trajectory”, which meant it was fired almost straight up. Had it been flown to maximise reach, it had a potential range of 13,035km, or the ability to strike Washington, DC. The US capital is 11,000km from Pyongyang. Potential targets in Australia are about 7000km away.

That reflects the gravity and urgency of the challenge implicit in Kim’s latest act of defiance. It underlines the need for Donald Trump and, hopefully, Chinese leader Xi Jinping to redouble their efforts to bring the demented despot in Pyongyang to heel.

It is, of course, a quantum leap from test firing ICBMs that end up in the Sea of Japan to turning them into weapons of mass destruction with nuclear warheads capable of striking targets across the US and Australia. But Mr Mattis’s highlighting of the technical advances North Korea has made emphasises the urgency of halting this program. Mr Trump’s 12-day Asian odyssey clearly has done nothing to deter Kim. Neither has anything Mr Xi has done on the economic front. With the winter biting and China (it says) cutting back on oil supplies, Kim remains obdurate. He appears unmoved by Mr Trump’s restoration of North Korea to the US list of state sponsors of terrorism alongside Iran, Syria and Sudan.

US Secretary of State Rex Tillerson declared “diplomatic options remain viable and open, for now”. The key to ending the escalation in North Korea’s technical advances in this nuclear crisis remains, as always, in China’s use of its leverage to rein in Kim.