Like soccer, the US presidential first term is a game of two halves. In the first two years, the president tries to leave his mark on Washington and enact his promises. In the second, re-election becomes the goal. In this respect only, Donald Trump is conforming to type. In all others, he is blazing a unique trail.

Mr Trump’s presidency has been a garish spectacle that could just as easily lead to his impeachment in the months ahead — or his resignation in exchange for immunity — as in his re-election in 2020. Much like Britain, which faces outcomes as extreme as a no-deal Brexit and a second referendum, America is in the throes of radical uncertainty. With Democrats taking over the House of Representatives, and Robert Mueller’s Russia collusion probe nearing its end game, the Trump presidency now faces far greater volatility. To paraphrase one of his predecessors: “We ain’t seen nothing yet.”

His biggest turning point was the Democratic “blue wave” in November. Having pulled out every trick in his box, including sending troops to the US-Mexico border, Mr Trump was un-able to stop a Republican defeat in the House of Representatives. He blamed everyone but himself for a campaign that he had ensured was about anything but a booming economy. That defeat has sharply reduced his ability to intimidate friends and foes alike.