All over the world there are countries that rely on the protection and leadership of the US. But dependable old Uncle Sam seems to have gone on a long vacation — and his malicious twin, Uncle Donald, has taken up residence in the White House. The result is confusion and soul-searching among some of America’s closest allies.

Three countries — Britain, Australia and Japan — exemplify the problem. All three pride themselves on their close relationships with the US. All three are currently led by centre-right governments that would normally expect good relations with a Republican president.

And yet all three have seen their prime ministers humiliated or put in excruciatingly awkward situations by Mr Trump. The most recent example came with the president’s retweeting of anti-Muslim videos from a far-right group in Britain. The result has been an unseemly, unprecedented and wholly unnecessary row between the US president and the British prime minister. Mr Trump’s much-deferred “state visit” to Britain is now disappearing into the dim-and-distant future.