John Major, Tony Blair and Gordon Brown have warned of the dangers of Brexit. But where is the former prime minister who called the referendum that will blight Britain for as far ahead as anyone can see? Whatever happened to that likely lad? David Cameron doesn’t want to talk about it, one of his friends tells me. “He doesn’t defend the referendum, but won’t say he made a mistake either. Europe is like a family scandal. We know what’s happened but we don’t say a word: it’s his no-go zone.”

At a personal level, the consequences swirl around him. I may be exhausting your capacity for compassion but the smallest of the casualties of Brexit has been the good fellowship of the Chipping Norton set. Naturally, the Cotswolds’ wealthy Leavers are grateful. But Cameron must resent them. He must know that he has been the useful idiot who succumbed to the demands of Rupert Murdoch’s Rebekah Brooks, a member of the local nouveau gentry by virtue of her converted barn, in the crashingly stupid belief that no harm would come from his surrender.

Invitations to “kitchen suppers” from Remainers, however, can only include Samantha Cameron’s name – if, they are extended at all. Tania Rotherwick invited the Camerons to her pool at the magnificent Cornbury Park estate before she split from her husband and Cameron split Britain from Europe. She is now particularly contemptuous, I hear.

Cameron’s memoirs were meant to be published this month but have been delayed until next year. The early signs are ominous. A book has to be coherent if it is to find a readership: its opening must prefigure its conclusion. As described in the publishing press, Cameron’s effort will have no consistency. He will tell the story of the formation of the coalition, his contributions to economic, welfare and foreign policy, his surprise victory in the 2015 election and then – as if from nowhere – the conventional memoir will end with the author carelessly deciding he will settle the European question, without planning a campaign or preparing an argument and, instead, launching a crisis that will last for decades. Nothing will make sense. Nothing will hang together. It’s as if a romcom were to conclude with serial killers murdering the cooing lovers or Hilary Mantel were to have aliens invade Tudor England on the last page of her Thomas Cromwell trilogy.

The book Cameron cannot write would accept that his political battles and achievements were as nothing when set against his decision to appeal to the worst of the Tory party. It would begin with Cameron honouring the decision that won him the Conservative leadership in 2005. He would confess that he should have known better than to pull the Conservatives out of the centre-right group in the European parliament and align them with Law and Justice, the know-nothing Polish nationalists who are reducing their country to an ill-governed autocracy. The manoeuvre was pure Cameron: tactics above strategy; appeasement instead of confrontation.

The pattern continued throughout his premiership. He thought he could buy off the right by refusing to explain the benefits of EU membership to the voters. At one point in 2014 he threatened to leave the EU. He then turned around in 2016 and asked the public to believe that leaving would be a disaster and was surprised when 17.4 million men and women he had never treated as adults worthy of inclusion in a serious conversation ignored him.

If he were being honest, Cameron would admit too that Brexit ought to bring an end to a British or, to be specific, English, style that is by no means confined to the upper class, but was everywhere present among the public-school boys who ruled us.

‘One Etonian led the Remain campaign and another led the Leave campaign, and the English couldn’t see why that was wrong.’ Photograph: Frantzesco Kangaris/The Guardian

I mean the ironic style that gives us our famously impenetrable sense of humour (which we will need now the rest of the world is laughing at us). The perfidious style that allows us to hide behind masks and has made England superb at producing brilliant actors for the West End but hopeless at producing practical politicians for Westminster. The teasing style of speaking in codes that benighted foreigners can never understand, however well they speak English. The cliquey style that treats England as a club, not a country, and allowed Jeremy Corbyn to say that Jews cannot “understand English irony”, however long their ancestors have lived here.

The deferential style that allowed one Etonian to lead the Remain campaign and another to lead the Leave campaign and for the English to not even see why that was wrong. The life’s-a-game-you-shouldn’t-take-too-seriously style that inspired Cameron to say he holds “no grudges” against Boris Johnson now the match is over and the covers back on the pitch. The gentleman amateur style that convinced Cameron he could treat a momentous decision like an Oxford essay crisis and charm the electorate into agreeing with him in a couple of weeks, as if voters were a sherry-soaked don who could be won round with a few clever asides. The effortlessly superior style that never makes the effort to ask what the hell the English have to feel superior about. The gutless, dilettantish and fatally flippant style that has dominated England for so long and failed it so completely. The time for its funeral has long passed.

A politician who bumped into Cameron said he thinks the referendum result must be respected, but that Britain should protect living standards by going for the softest Brexit imaginable and staying in the single market. This is a compromise well to the “left” of Theresa May and Corbyn’s plans and is worth discussing. Whatever his critics say, David Cameron is a former PM. He not only has the right to offer his solution but a duty. If he is to earn the right to a hearing, however, he must first find not only self-knowledge and courage, but an un-English seriousness of purpose he has evaded all his life.

• Nick Cohen is an Observer columnist