What Bolton’s memoir does reveal is the limits of President Trump’s improvisational and transactional approach to foreign policy. Trump is winging everything all the time, as most keen observers have been able to tell. He may, at some mysterious level, be playing three-dimensional chess on the world stage, but he is conspicuously ignorant on important subjects. According to Bolton, he didn’t even know Britain was a nuclear power.

‘I have two groups of people,’ said President Donald Trump last year. ‘I have doves and I have hawks. John Bolton is absolutely a hawk. If it was up to him, he’d take on the whole world at one time, ok? But that doesn’t matter, because I want both sides.’

President Donald Trump regards himself as America’s CEO in world affairs. In his head, he’s isn’t a hawk or a dove – he’s the big bald eagle who sits atop the greatest military power in the universe and calls the shots. Trump listens to pitches from advisers with different or opposing perspectives, then makes an executive decision, or doesn’t. This approach has its merits: it helps explain why Trump hasn’t got sucked into disastrous wars as his predecessors have done. As we’ve seen with North Korea, to Europe, to China, to Iran, Trump’s modus operandi is to be flexible. It also creates a usefully unpredictable will-he-won’t-he dynamic in his approached to all foreign problems – from North Korea to China to Venezuela and Iran.