The far right does not seize power. It is invited in to power by mainstream conservatives, who boast of their commitment to free societies. They do it for partisan gain. They do it because they hate and fear the left more than they hate and fear the far right. But most of all they do it because they have run out of ideas. The energy and the votes appear to lie with radical rather than “respectable” conservatives. The future is extreme, and, like prostitutes turning a trick, conservatives would rather lose their respectability than their chance of staying in the game.

Leftish condemnations of “neoliberalism” miss that the Thatcher/Reagan ideology of the 1980s is over. Conservatives rarely admit it, in public at any rate, but an idea is still dead even if no one turns up for the funeral. Who can now pretend hopes that a small state and free markets would bring prosperity to the mass of people are anything more than a hollow joke? The 2010s have been the worst decade for wage growth in 200 years. The real value of average wages has still not staggered back to its 2007 level. The web’s enabling of fake news gets all the attention. But if it had never been invented, there would still have been a reaction against the emptiness of the promises of the old ruling order.

Put yourself in the place of the conservatives who thought Ronald Reagan’s and Margaret Thatcher’s certainties would sustain them. They have learned the lesson of the 2010s that fear beats hope. They have heard the audience cheer when they bash immigrants and the EU, and fall silent when they talk of compromise and tolerance. They wonder what would happen if its rage were directed at them rather than convenient scapegoats.

Is an endorsement of a Trump, Salvini, Farage or Orbán such a high price to pay in these circumstances? Traditional conservatives can mock them in private and drop careful hints in public that they come from an altogether classier version of conservatism. But when the choice has to be made, they will go with them rather than fight them. Better that than become a historical curiosity: the left-behind of rightwing politics.

A Sicilian aristocrat in Giuseppe Tomasi di Lampedusa’s great novel, The Leopard, says: “If we want things to stay as they are, things will have to change.” The line is trotted out when writers want to encapsulate how an old ruling class must adapt to survive the arrival of democracy, the rise of the middle class or the demands of the working class; in other words, how it must change to accommodate movements you can broadly describe as progressive. But radical shocks to the old order don’t always come from “the left”. Nor does the urge to destroy. Thatcherism, Islamism, Hindu, Christian and Jewish religious fanaticism and today’s populism show that for the last 50 years the counter-revolution has outpaced the revolution more often than not.

The Leopard begins with Garibaldi’s red shirts arriving in Sicily in 1860. Its final scene is set in 1910. In 1922, the Italian king Victor Emmanuel III refused to allow the military to stop Mussolini’s forces marching on Rome and allowed him to take power instead. For things to stay the same, he realised the change the old Italian aristocracy had to endorse was the world’s first fascist state. Lampedusa looked on with approval. “Even if a revolution breaks out, no one will touch a hair on my head or steal one penny from me,” he wrote in 1925, “because by my side I have… Mussolini!”

Boris Johnson played with fire to become prime minister and must keep fanning the flames if he is to survive

Times change but the survival instinct does not. The capitulations of conservatism are so commonplace we barely notice them. For the record, it is worth mentioning that the few principled conservatives left in the United States keep lists of their former friends who could not sustain their opposition to Donald Trump.

What unites Senator Lindsey Graham, say, with Paul Ryan, and Rupert Murdoch’s employees at Fox News is that, when it came to the moment of decision, all their talk about free trade and free markets, fiscal discipline and family values counted for nothing when set against the danger of alienating the new forces on the right.

The autocracies in eastern Europe have flourished under the protection of Angela Merkel and the impeccably well-mannered conservatives in the European People’s Party. Like Donald Trump, Viktor Orbán is against everything they believe in – or say they believe in: a free press, independent judiciary, a free market where corruption has no place. Yet European conservatives protected Orbán from sanctions. Nurtured by the respectable right, Europe’s populist states celebrated their invitation to the high table by blocking the appointment of the Dutch diplomat Frans Timmermans as European commission president for fear he would force them to live by the democratic standards that conservatives pretend to share.

In Britain we have the abject figures of George Osborne, Matt Hancock and Damian Green who know a no-deal Brexit is a disaster but are endorsing Boris Johnson because they want his patronage. Journalists who claim to understand Johnson say he is at heart a liberal. Assuming he has a heart, he may be, but his motives no longer matter. He played with fire to become prime minister, and must keep fanning the flames if he is to survive. Like many others, he found that the way to win was to direct hatred at the EU. He will discover that the way to avoid a reckoning with the failures of the old order will be to keep anger directed at foreigners.

“I belong to an unlucky generation,” says a character in The Leopard, “astride between two worlds and ill-at-ease in both.” Whatever the cost to their integrity, whatever the suffering they inflict on others, the worst of today’s conservatives are determined to ensure that they are at ease with the world the radical right creates and it is at ease with them.

• Nick Cohen is an Observer columnist