With the irreversible fact of Brexit and the formation of the May government, British politics has undergone a regime change more fundamental than the one signalled by Margaret Thatcher’s coming to power in 1979. Like Thatcher, Theresa May and those advising her have “glimpsed the future and run with it” – as Martin Jacques wrote of the Thatcherites three decades ago. But this is not a rerun of Thatcherism: quite the contrary. If it delivers on half of its prospectus, this will be the first British government that is definitively post-Thatcherite. By abandoning the fiscal orthodoxy that shaped official thinking from Blair and Brown to Cameron and Osborne, accepting the need for a national industrial strategy and reasserting the role of the state as the final guarantor of social cohesion, the May government has broken with the neoliberal model that has ruled British politics since the 1980s.

It is telling that the break with neoliberalism has come from the right. Today, as in the late 1970s and early 1980s, the left has yoked itself to failed projects and dead ideas. Then, they were nationalisation and unilateral nuclear disarmament. Now they are the European Union and a bien-pensant approach to immigration that denies the costs of the uncontrolled movement of labour to working people. Labour moderates are as tethered to these positions as the Corbynites. Taking the delusion and denial gripping the shattered centre left to an absurdist conclusion, Owen Smith made rejoining the European Union once Brexit has been completed a central theme of his leadership campaign and suggested Britain should consider entering the eurozone and the Schengen area. He forgets the millions of Labour voters who rejected Britain’s membership of the EU in the June referendum.

Talk of realignment on the centre ground exposes a failure to understand how the ground has shifted. With Corbyn’s re-election and an ensuing campaign to deselect MPs whose loyalties are suspect, Labour will not split, but become fully Corbynised – an inchoate, anti-capitalist mass movement with a shrunken and cowed parliamentary wing. Equally, despite rumblings against grammar schools from washed-up Cameroons and George Osborne surfacing in the media to resume his career as a political gambler, there is zero likelihood of any breakaway movement among the Tories; the realistic prospect of decades of unopposed power is much too tempting to jeopardise. Paddy Ashdown and others who dream of forming a new centrist grouping belong in an ancien régime that vanished without trace along with Cameron’s petulant but welcome decision to quit as an MP. The only possible realignment in British politics – the disappearance of the centre left as a significant force – has already occurred.

The debacle of the left is one of the defining facts of our time. The irony is that it has come about because of a crisis in capitalism. Anyone who thought the near-collapse of the global financial system would open up a “social-democratic moment” had not bothered to consider what voters want in times of economic upheaval. More sceptical in their thinking than progressive elites, most people are unimpressed by visions of an ­imaginary egalitarian capitalism. They turn instead to the power of the state to protect them from the anarchy of the market.

The resurgence of the state is one of the ways in which the present time differs from the “new times” diagnosed by Martin Jacques and other commentators in the 1980s. Then, it seemed national boundaries were melting away and a global free market was coming into being. It’s a prospect I never found credible. A globalised economy existed before 1914, but it rested on a lack of democracy. Unchecked mobility of capital and labour may raise productivity and create wealth on an unprecedented scale, but it is also highly disruptive in its impact on the lives of working people – particularly when capitalism hits one of its periodic crises. When the global market gets into grave trouble, neoliberalism is junked in order to meet a popular demand for security. That is what is happening today.

If the tension between global capitalism and the nation state was one of the contradictions of Thatcherism, the conflict between globalisation and democracy has undone the left. From Bill Clinton and Tony Blair onwards, the centre left embraced the project of a global free market with an enthusiasm as ardent as any on the right. If globalisation was at odds with social cohesion, society had to be re-engineered to become an adjunct of the market. The result was that large sections of the population were left to moulder in stagnation or poverty, some without any prospect of finding a productive place in society.

History may look on Hillary Clinton’s struggle for the presidency as the closing act in the neoliberal experiment. More than the mistrust she inspires in many voters, or the issues surrounding her health, more even than her Mitt Romney-like dismissal of a sizable section of US voters as “a basket of deplorables”, it is the fact that she is identified with this failed experiment and with those who have most profited from it that casts the longest shadow over her candidacy. Few of those who end up voting for Clinton will do so because they expect her to bring about deep change in the economy. Many will do so from fear of the alternative. But how many other Americans will be ready to roll the dice and opt for Trump, simply in order to impose change of some sort on the entrenched oligarchies and rigged political system that Clinton represents and embodies to them? Until the votes are counted, it is a question that cannot be answered, but it’s a safe bet that there will be more than have yet revealed themselves to pollsters.

If the 1980s were a time when the global market was expanding, our time is one in which globalisation is stalled and fragmenting. Idle dreams of a global free market have yielded to geopolitical rivalries, while anxious populations want safety more than fast-increasing material prosperity. A circulation of elites is under way, in which those that cling to the neoliberal past are being replaced by others that understand the present. The long fag end of the 1980s is over.

In Britain the May government will have to perform a tricky balancing act. In recognising that an unstable global environment requires a reassertion of the protective ­functions of the state, it is ahead of the game. As the Hinkley Point C saga shows, reconciling that role with the need for continuing trade and investment will be a formidable task. But it is the right that has grasped what the new times mean. The left is once again a sideshow.

John Gray is a philosopher and the lead book reviewer of the New Statesman

This article is part of a New Times collection of the future of the left. Read the other pieces here.