Towards the end of Sunday’s second televised US presidential debate, Hillary Clinton said something that political candidates often say, but which in 2016 is no longer the usual banality. “This is not an ordinary time,” said Mrs Clinton. “And this is not an ordinary election.” If anything, this was an understatement. The second debate between her and Donald Trump, and the days running up to it, have been extraordinary living and livid proof of that.

Rarely in any democratic country, never mind in the world’s most powerful democracy, can the substance and the temper of the debate have been so low, so dark, so personal and so damaging as it has now become in the US race. The responsibility for this cannot be dismissed as six of one and half a dozen of the other. The responsibility for it rests squarely with Mr Trump, his campaign and his personality. To take just one example: in most democracies, the tape that exploded into the public arena at the end of last week, in which Mr Trump was heard boasting about his sexual aggression towards women, would have destroyed his candidacy. He would have been forced to quit, partly because of the offensiveness of his words and views, and partly so his party’s other candidates can save their electoral skins.

Yet not only did Mr Trump brazen the tape out at the weekend, but on Sunday night he deliberately went lower and darker still. Shortly before the debate, Mr Trump held a press conference championing women who claim to have been Bill Clinton’s past sexual targets. This attempt to fan the stone-cold embers of arguments that distracted and demeaned America nearly 20 years ago was a clear signal. It showed that Mr Trump will fight as dirty as he can, all the way to November. It also suggested that his focus is on firing up the angriest and most paranoid parts of the Republican vote. This was confirmed once the debate was under way, when Mr Trump insulted, abused and patronised Mrs Clinton at every opportunity, both in his words and by the intimidatory platform manner that his admirer Nigel Farage revealingly likened to the dominant behaviour of a silverback gorilla.

There have been other bitter presidential contests in the US. Yet this contest has become a break with the past that will not be easily repaired and for which America will pay a price at home and abroad, whatever the outcome next month. When before did one candidate say of another in debate that they have “tremendous hate” in their heart? Or refer to his opponent as the devil? And when before did one candidate say, as Mr Trump did, that, if elected, he would try to see his opponent prosecuted and put in jail. That’s what happens in autocracies and dictatorships. It’s the way leaders behave in countries with no respect for the rule of law or the separation of powers. But it has not been the way, until now, in America.

Mr Trump does all this partly because that is the kind of person he is: impulsive, rude, aggressive, extreme. He does it partly because there has always been something violent and vengeful about the white right in the US. And he does it partly because his rise has been one manifestation of a global anger against democracy’s failures to control the rich and compensate the poor.

But it is no accident that this is happening in the first US presidential race in which a woman may win. Of course, Mr Trump would behave aggressively if his Democratic opponent were a man too. He’s that kind of bully. But his anger through the campaign, and in Sunday’s debate, is the anger of a man who cannot treat women as equals. In another remark in the debate Mrs Clinton said her vision of America is of somewhere where everyone has a place. Mr Trump’s view of women’s place does not bear thinking about – and should not be voted for.