In an era of populist leaders, we are getting used to the idea that nobody ever apologises for anything.

In the past, the etiquette was clear. If you said something wrong, or you made a wrong call and were reversing your policy stance, you were expected to admit it, apologise, and move on. Sure, the apologies could be limited and hemmed in with weasel words, yet it was accepted that not only was this the right thing to do but it was better electorally than having this hanging over your head for ever.