An intriguing theory has recently taken hold, fast calcifying into received wisdom. Hillary Clinton, so it goes, lost the US election because she “played identity politics”.

This idea has been enthusiastically endorsed by, among others, Bernie Sanders (“It is not enough for somebody to say, ‘I’m a woman, vote for me,’” he said, as if Clinton ever – even once – argued this), and Mark Lilla in the New York Times (who described as “a strategic mistake “Clinton’s tendency “to slip into the rhetoric of diversity, calling out explicitly to African-American, Latino, LGBT and women voters at every stop”).

Like I say, it’s a fascinating theory, in its underlying insinuations and its demonstrable wrongness. (To point out that – in the vast, vast main – the identity politics sceptics are white men, whose articles are filled with quotes from other white men, doubtless sounds like I’m playing the identity game, too; and yet it is one of those awkward things called “facts”.)

Leaving aside that far more people voted for Clinton than Donald Trump (an inconvenient truth for any sweeping argument about why Clinton lost), the real issue is not that Clinton lost the election. On the contrary, it’s that playing identity politics is precisely how Trump won the election. Anyone who can’t see that is revealing that they think the white straight male as the baseline norm. Thus anyone else – women, people of colour, LGBT people – is merely a niche distraction, a gimmicky aberration, a game (“as if the centuries’-long push toward enfranchisement, civil rights, equal pay, and reproductive autonomy, and against domestic, sexual, and police violence were a game”, Rebecca Traister recently wrote). They are not, as the political phrasing goes, real people.

It boggles my brain that this even needs pointing out: political elections have always played identity politics. The difference is that the game was heretofore entirely weighted towards the white straight male, which I guess is why it comes as such a shock to that demographic when they are not at the absolute forefront of every single political discussion now.

Lilla, for example, in his much-discussed article, suggested that the politicians who “very skilfully” bridged identity divides were – wait for it – Ronald Reagan and Bill Clinton. Ah yes, this would be Reagan, who enthusiastically blew the racial dog whistle by referring to “a Chicago welfare queen” and “a strapping young buck” who used food stamps to buy steaks. And Clinton, who to prove that he was tough on crime interrupted his own 1992 campaign to return to Arkansas to preside over the execution of Ricky Ray Rector, an intellectually impaired black man. Both reinforced discrimination against LGBT people.

But this was not divisive identity politics, apparently, because white straight voters don’t have an identity – they are just people. This, I guess, is why some seem unable to see that Trump (and his new BFF, Nigel Farage, this country’s most expert practitioner in the sport) ran campaigns this year entirely predicated on identity politics.

No, no, Trump’s campaign was about the economy, his defenders cry! And indeed it was, in that Trump promised the old manufacturing jobs would come back to the overwhelmingly white rural areas (which almost certainly won’t happen), and massive tax cuts to the white super-rich (which almost certainly will). See if you can spot the common denominator in those demographics.

Discussions about identity politics are the new arguments about political correctness, which, as Moira Weigel detailed at length in this paper this week, have long been a means for the male, white and right mainstream to shut down any suggestion that others are worthy of a voice. For Clinton even to acknowledge that she was the first female candidate of a major political party – which is very different from saying people should vote for her because she is a woman – was, according to the sceptics, to play the identity game.

What is less acknowledged by these people – and can be fatally forgotten by some on the left – is that class is as much a part of identity politics as race, religion and sexuality. This has been Sanders’s point since the election: “Yes, we need more candidates of diversity, but we also need candidates to be fighters for the working class,” he says, which is all well and good. But the working class is not an ethnically homogeneous group, and within those divisions there are distinct differences and needs. As Jamelle Bouie wrote this week, “not all inequality is created equal. On average, inequality and poverty among black Americans (as well as native groups and undocumented Americans) is of a different scale and magnitude than inequality and poverty among white Americans.”

And yet 88% of African-Americans and 65% of Latinos voted for Clinton. That Clinton lost the election is further evidence that the electoral college system is itself bogged down in identity politics, given its bias towards white voters, with one vote in the white rural states worth as much as three votes in states such as California with racially diverse big cities.

The so-called alt-right – which I think is Latin for “old racism” – movement likes to suggest that identity politics are just about overly sensitive minorities whining over hurt feelings: college students protesting against the cultural insensitivity of serving sushi in the school cafeteria, say. It is to the left’s detriment that it has allowed these absurd extremes to obscure the real point, which is that where one begins in life – and how far one can generally go – is still determined by identity: racial, economic, gender and sexual, in pretty much that order.

In general, a white man automatically has an economic advantage over a woman or person of colour from the same class, although God help anyone who dares to point that out to certain white men. As writer Ta-Nehisi Coates tweeted on Thursday, “Notion that white dude’s issues are ‘economic’ and everyone else is just trying to discuss their feelings is, well, sorta deplorable.”

Identity politics sceptics ask why we can’t just emphasise what we have in common instead of focusing on the differences. And what a delightfully kumbaya vision of the world that is. Sadly, that’s a little tricky, given that white American voters just elected a man whose campaign repeatedly insulted Muslims, Jews and women, and whose cabinet choices unanimously oppose LGBT rights.

So when people say identity politics exacerbates differences, it’s hard not to suspect that what they’re objecting to is not the acknowledgement of differences but the existence of differences, full stop.