Elections come with their own rituals. The big night demands Dimblevision and swingometers and some low-budget jape that presumably sounded good in production meetings. But one thing 8 June won’t be is normal. There is no point in journalists reporting this as a horse race, when all the polls predict a bloodbath. It is futile for specialists to pick apart policy promises made in spring 2017 when the next few years’ haggling over Brexit will upend everything from the safeguards on the food we eat to our relations with other countries.

Most important, it is delusional to treat this as just another vote, when Theresa May and her outriders are intent on turning it into a culture war. June is shaping up to become a hinge point in British politics: the moment a venom was injected into public discourse.

To see how culture wars wreck a society, look at Donald Trump’s America. The huckster seized the White House by pitting middle America against the coastal elites, whites against migrants, the Christian right against Muslims and women who want the right to choose. He didn’t need serious policies while he was working through the deck of identity cards. He didn’t bother with a vision because he was too busy orchestrating hate. The pundits who judged him by conventional political yardsticks missed the point. Trump wasn’t playing politics: he was prosecuting a culture war – and a culture war is anti-politics.

This is not how the British do things. On this small island, politics is supposedly about millions of people with opposed interests arguing out their differences before arriving at a resolution. That’s the ideal and, honestly, you don’t need to tell me that the reality often falls short because I’ve moaned enough about it in the Guardian. But what Theresa May offered last week was not even pretending to be politics; she was instead cranking up a culture war.

First came her speech about how “the country is coming together”, even while her political opponents were not. Her cheerleaders were in the press the next day, baying for “Blue murder” and for her to “Crush the saboteurs”. I watched all this from the US; and in the land where Democrats are now routinely labelled “treasonous” it all sounded eerily familiar: us v them; the people v Westminster; leavers v remainers.

Never mind that May is one of those elite professional politicians she is now decrying. Forget that she’d been a remainer. The whole point of culture wars is that the generals look nothing like the people they wish to recruit as foot soldiers: take the people’s billionaire, Donald Trump.

To see where May is leading Britain, I picked up one of the great contemporary histories of America. In Nixonland, Rick Perlstein charts how his country turned to all-out culture war. Perlstein dates the process back to Richard Nixon, who in the late 60s successfully “forged a public language that promised mastery of the strange new angers, anxieties, and resentments wracking the nation”. By 1972 he had won a landslide victory.

I defy any Briton to read Perlstein’s description of this “brilliant and tormented man”, completely devoid of the glad-handing or baby-kissing skills of the natural politician, and not think about a leader closer to home. In 1972 Nixon’s attack dogs destroyed his Democratic opponent, George McGovern, by defining him as the candidate of “amnesty, abortion, and acid”. You can already see how Jeremy Corbyn will be tagged as the friend of Hamas, Hezbollah and tax hikes.

You can already see how Jeremy Corbyn will be tagged as the friend of Hamas, Hezbollah and tax hikes

Nixon appealed to the “silent majority”. In Britain it was the hard-right Nigel Farage who greeted the Brexit vote as “a victory for real people”. May picked that up and turned it into “the ordinary people” rebelling against the elite. And it was her aide, Nick Timothy, who reportedly came up with the line about how “if you believe you are a citizen of the world, you are a citizen of nowhere”. Just as Nixon did, and within a similarly short period of time, the May camp has taken a language previously found only on the fringes of the right, and made it mainstream.

Previous generations of Tories have flirted with identity politics. Margaret Thatcher attacked the miners as “the enemy within”. When pushing through their historic spending cuts, David Cameron and George Osborne claimed they were punishing the “skivers”, not the “strivers” – even though they were taking cash off the working poor and people with disabilities.

But three things are different this time. First, as home secretary May spent six years trialling this form of culture politics – and if she retains any squeamishness, it doesn’t show. Never forget that she deployed into areas of high immigration vans reading “Go Home”. Second, social media has exacerbated the politics of identity. All those Twibbons and shared petitions. All that Facebooking about how I am a Bernie Bro and you are a Deplorable, while she is part of the Pantsuit Nation. This kind of self-identification must be part of the business model for Facebook and Twitter: all the better to direct-market you with.

Finally, the Brexit vote did reveal deep cultural differences between leavers and remainers. A study published last year by the NatCen social research institute found the EU referendum’s 48:52 split was “less about a traditional left-right battle and more about identity and values”. Confronted by a statement such as “young people today don’t have enough respect for traditional British values”, leave voters would be far more likely to nod, leading the report’s author to conclude that this was “a strong sign that the … culture wars of the US have arrived in Great Britain in earnest”.

Such differences in attitudes are hardly new, but the current crop at Westminster no longer know how to deal with them politically. Not after 30 years in which eager young Oxford PPE-ists have seen politics as being all about capturing Mondeo man and not scaring the City.

May’s solution is to turn Britain into a one-party state. After June she will probably have a once-in-a-generation majority, and the mandate to define Brexit any way she wants. A Conservative using the language of the hard right will have won the battle to define the very identity of Britain. That is what makes 8 June unlike any other election I can remember.