“Never,” Rod Liddle writes in his jeremiad on the “betrayal” of Brexit, “have so many blameless people in this country been held in such contempt, or been subject to such vilification by an elite.” Really? Who wrote in 2014 of Britain as “a nation of broken families clamouring about their entitlements siring ill-educated and undisciplined kids unfamiliar with the concept of right and wrong”? Who described with relish “the hulking fat tattooed chavmonkey standing in the queue at Burger King”? Who characterised the British masses as inhabiting “a dumbed-down culture”, being in thrall to “the background fugue of idiocy, the moronic inferno, of celebrity fuckstories”, and spending their time “watching TV, masturbating to pornography on the internet, getting drunk”? That would be Liddle in his last book, whose title, Selfish Whining Monkeys, may just possibly have had a slight whiff of contempt and vilification.

But that was then, this is now. Liddle’s “chavmonkeys” have been redeemed by the Brexit referendum. Their “fugue of idiocy” is now a swelling symphony of reasserted sovereignty, their “dumbed-down culture” a fount of wisdom. The man who saw a “the moronic inferno” now champions the people against the “stereotype of the decrepit moron Leave voter”. For now, apparently, it is liberal remainers who commit the unforgivable sin of calling those voters stupid, “uneducated thickos” – and racists to boot. The evidence for this contention, as for everything else in Liddle’s polemic, is vanishingly thin. Yet the claim is central to his diagnosis of “a grotesque and unprecedented betrayal of the country” by the BBC, parliament, the judiciary, the civil service, Theresa May’s government and of course the “Irish spite” embodied in that “oily little shit”, the taoiseach Leo Varadkar.

Liddle recalls that on the morning of the referendum result in 2016, he posted a one-line message on his Facebook page: “Betcha we don’t leave.” He now adds that he and his wife agreed that “they won’t let it happen”. Thus his narrative of Brexit betrayed is not a response to events since that (for him) glorious morning. It is the chronicle of a death foretold. And in a sense, this intuition of inevitable failure was quite right. Failure was baked in. The promise of a Brexit that delivered all the benefits of EU membership with none of the costs could not survive contact with reality. Brexit was not “betrayed”. It was dead on arrival.

What makes Liddle’s book so dishonest is that he seems well aware of this, but persists with his pre‑prepared tale of treachery nonetheless. He accepts that Donald Tusk “had a point” when he spoke of a special place in hell for those who urged people to vote leave without having a plan for Brexit. He concedes that the leave campaign was “utterly lost” in the aftermath of its victory: “There was no sense of direction, no notion of a strategy, no notion as to how to proceed from here.” How can a non-existent project, one that is already “utterly lost”, be betrayed? Can a strategy that has never been created be thwarted by traitors?

Facebook Twitter Pinterest Rod Liddle now champions ‘the people’ against the ‘stereotype of the decrepit moron Leave voter’. Photograph: Colin McPherson/Corbis/Getty Images

Tellingly, Liddle specifies the moment of perfidy. The conspiracy, as he sees it, began as soon as “the establishment” started talking about a “hard Brexit” and a “soft Brexit”, “whereas hitherto we had simply been talking about Brexit”. In other words, the betrayal started as soon as “Brexit” acquired any actual content. Once “Brexit means Brexit” became “Brexit means this or that”, it was being sold out. There is here a kind of truth – the pure, unbetrayed Brexit could exist only in the abstract. To give it concrete meaning was to sully it. Nowhere does Liddle ever tell us what he himself actually thinks Brexit means in the real world. How could he, since by his own definition that would be an act of betrayal?

Of a piece is Liddle’s suggestion that Brexit was betrayed because its implementation was allowed to pass into the “hands of politicians … and away from the people who had voted”. How exactly does he think “the people who had voted” were supposed to negotiate the mutual rights of citizens, the divorce bill, the UK-Ireland border and a vastly complex trade deal? Even conceding that the people who were, in Liddle’s pre-Brexit rantings, so sunk in idiocy five years ago, are now intellectual giants, how might this process be managed? Might the people, perhaps, elect delegates to some kind of representative assembly which in turn would choose an executive?

Liddle is as untroubled by facts as by logic. He repeatedly cites the figure of £9bn as the UK’s annual net contribution to the EU – it is £7.9bn. The House of Commons library report of 24 June on the net contribution says the £9bn does not take account of EU funds given to non governmental agencies in the UK (universities and so on). He thinks Ireland was “forced” by the EU to hold another referendum on the Nice treaty in 2001 – it wasn’t. He thinks the DUP speaks for “the Northern Irish”, even though it gets a third of the vote and does not represent the strongly anti-Brexit majority. He claims Britain could have negotiated a trade deal with the EU before it discussed a withdrawal agreement, even though the EU can’t do a trade deal with Britain until it has actually left. His understanding of the border question – blockchain can solve “almost all” the problems – is childish. He even seems oblivious to the basic history of the UK: “Our boundaries have not shifted much over the years.” (So Ireland neither joined the UK in 1801 nor left it in 1922?)

Facebook Twitter Pinterest A shop in Dudley in the West Midlands, where the majority of the 2016 referendum voters opted to leave the EU. Photograph: Christopher Thomond/The Guardian

At the heart of Liddle’s new pose as defender of the people is his righteous rage against “the allegations that Leave voters were all racists”. His only actual source for this “allegation” is Diane Abbott, who Liddle quotes as saying that “people who intended voting Leave ‘want to see less foreign-looking people on their streets’”. Abbott did not say this about people who intended to vote leave. She said it on Question Time in April 2017, long after the vote. She did not say it about leave voters as a whole – she actually said: “The people that complain about the freedom of movement will not be satisfied because what they really want is to see less foreign-looking people on their streets.” And she also added that she would “never say that people voted to come out because they were racist”. This is the sole foundation for Liddle’s core argument.

Equally disingenuous, though, is his contention that racism and xenophobia played no role at all in the leave vote. The grossly misleading posters showing brown-skin hordes supposedly queueing to get into the EU were “a matter of taste rather than accuracy”. He acknowledges that the use by the official leave campaign of Turkey’s allegedly imminent membership of the EU was “a little bit speculative”. But, he adds, it did not affect “a single vote, apart maybe from some Kurds”. He does not tell us how he knows this or whether he has explained to Nigel Farage, Boris Johnson and Dominic Cummings how they wasted so much money and effort in appealing to a non-existent xenophobia.

It is just as well that it does not exist. If it did, people might misunderstand the benign nature of Liddle’s questions about whether immigrants can have proper feelings for “the nation”: “If you are a fairly recent arrival in this country, does its long existence as a nation state matter very much to you? Do you have a stake in our history? Is the UK’s history as an independent country as impinging as it might be on someone whose family has lived here for countless generations?” He insists on giving one despised anti-Brexit campaigner her full name: “Gina Miller, née Singh” though he never refers, for example, to “Theresa May, née Brasier”. Otherwise readers might not realise that beneath Miller’s English-sounding name lurks a woman with no stake in “our” history. Here we face the underlying toxicity of the myth of betrayal. Without the treachery of those who do not belong to “us”, Brexit would always have been wonderful. Since it is not, we know who to blame.

• The Great Betrayal is published by Constable (£14.99). To order a copy go to guardianbookshop.com or call 0330 333 6846. Free UK p&p over £15, online orders only. Phone orders min p&p of £1.99.