It has been bothering me all day. Donald Trump seemed to win the latest televised debate, by which I mean he put in – at first glance – a stronger and ostensibly more focused performance than Hillary Clinton. Once again, as on the first occasion they debated, there was no knock-out blow from the Democrat and this time Trump appeared to dictate the terms.

Even so, watching the debate and then catching clips later in the day, it needled away at me. Had he really won?

It turned out within a day or two of the first debate that Clinton had won with voters after all, in unusual fashion simply by the clever act of giving Trump enough rope and standing back to watch. She resisted the temptation to spar and come back with zinging one liners. Perhaps she cannot do it. Either way, her strategy worked because in the final third of the first debate he flipped until he was left wittering incoherently about having been a complete pig to women and no-one understanding him. It was pathetic stuff. It doesn’t matter? Debates make no difference? In this election they matter, especially when it involves the whiny Trumpian meltdown of a blowhard buffoon, watched by ten of millions of voters and clipped endlessly for the news networks and social media.

St. Louis was different. Trump was stronger, all over it, asserting himself, playing the hard man, and Clinton seemed ill at ease. What was going on?

And then it hit me almost a day later. Whether it was deliberate or not (it looked planned, we’ll find out in the books on this historic election) she played it muted, letting Trump be Trump in all his inherent ghastliness. His outdated alpha-male strutting became so creepy that he began following her around the stage, crowding Clinton’s personal space and glowering.

Nigel Farage – the leader of UKIP – was on hand as a Trump surrogate for the US TV networks and declared that Trump had dominated Hillary and been a “silverback gorilla” on stage. Farage seemed quite excited by the spectacle of the ape marking out his territory. (Me Tarzan. You Jane.) That Trump as dominant gorilla comment may, unintentionally, be the most psychologically revealing thing Farage has ever said about anything.

At several points, when confronted by Trump, Clinton looked almost worried for her safety, like someone who has stepped into the wrong bar and cannot get out quickly enough to avoid the menacing, macho loudmouth at the bar looking to prove his masculinity.

Even the key cartoonish Trump moment – when he snapped “you’d be in jail” to Clinton – was transgressive and disturbing, like a scene from a Hollywood drama set in the American South in the 1950s or 1960s illustrating the perils of excessive power in the wrong hands. Or the imperious sneer of the baddie when the feisty little woman character dares to come out of the kitchen. In cinematic terms the jail line was the rhetoric of the prison governor in Shawshank Redemption. Or the arrogant local police chief in Mississippi Burning who thinks he makes the rules.

The “you’d be in jail” comment was such a clincher not just because Trump thinks being President means he can arrange to throw people in jail. He was really trying to show his core vote that Clinton should live by the same laws as everyone else, even though he misunderstands the US constitution. What gave it true menace was his demeanour. It suggested overwhelmingly a bad man, a damaged individual lacking dignity or respect for others, who compensates with bragging and bullying. A privileged New York reality TV star who has never served in the military yet who struts about as though he is the hard guy, who swaggers around trying to crush opponents and talks to Clinton in openly menacing terms. Is that man to be put in the White House and left in charge of nuclear weapons?

The initial polls and the turn against Trump since the tape was released on Friday suggest that sufficient American women voters in particular are processing this and – for all their reservations about Hillary – coming to a conclusion similar to that expressed so beautifully by Robert De Niro the other day in his best role since Goodfellas.

Clinton lost in St. Louis only in Trumpian terms. To lose in such circumstances, to such a bully, or what De Niro rightly termed “a punk and a bullshit artist,” is actually to win.

What a year. Thank goodness for women voters.