To hear Donald Trump speak of Kim Jong Un is to imagine a cartoon character — a “rocket man” on a “suicide mission”. To watch the US president’s deeds, however, is to discover that the North Korean dictator is not as crazy as he makes him out to be.

I am thinking here of Mr Trump’s expected refusal to certify that Iran is in compliance with the nuclear agreement reached with world powers in 2015. If you are Mr Kim, you would conclude that you have been right all along: the US cannot be trusted, even when it puts its name to an international agreement.

Seen from Pyongyang, the only way to deter an American invasion has always been to establish North Korea as a nuclear power that is both capable and willing to strike first or retaliate devastatingly. That is why China argues against excessive pressure on the regime. Mr Kim, says one official, would “prefer to die standing” than give in to the US.