It is a serious mistake for Trump to undermine his own Secretary of State and seemingly rule out all peacefully agreed solutions to the crisis with North Korea.

It will not be possible to stop the proliferation of nuclear weapons simply by threatening war. Yet he now appears to be on the verge of compounding that error by an action which, at a single stroke, will weaken America, splinter his allies and give Kim Jong-un every incentive to fulfil his nuclear ambitions.

In the coming days, Trump seems set to announce that he will no longer certify that Iran is complying with the nuclear deal the country signed in 2015 with six world powers, including Britain and America. Under this agreement – the Joint Comprehensive Plan of Action (JCPOA) – the Iranians agreed to dismantle or scale down their nuclear programme in return for the lifting of sanctions.