Before the general election, the Brexiteers would boast that everything had gone their way. Yes, those wretched judges had forced MPs to vote on whether to trigger Article 50 - but they had done so by a majority of 372. The Treasury-forecast recession hadn't occurred. And polls showed the public backing Brexit by a comfortable margin. After Theresa May, the Leavers' adopted empress, called an early election, they anticipated a remorseless march to victory.

But the Brexiteers' forward march was instead halted. Though 85 per cent of voters backed parties committed to Brexit (if not to the Tories' version), the political atmosphere has been transformed. The government is negotiating from a position of weakness, rather than of strength, and the mood is newly volatile.

Rather than making grandiloquent predictions of success, the Brexiteers are already preparing the ground for failure - and identifying scapegoats. In the House of Commons this morning, International Trade Secretary Liam Fox declared: "Some elements of our media would rather see the UK fail than Brexit succeed." A fortnight earlier, his cabinet colleague and fellow Brexiteer Andrea Leadsom denounced broadcasters for being insufficiently "patriotic". Behind such Trump-esque remarks lies the fear, as Vote Leave director Dominic Cummings recently put it, that "In some possible branches of the future leaving will be an error".

Two months after May hastily triggered Article 50, it is becoming ever clearer that the imperative of "sovereignty" cannot be reconciled with that of prosperity. In a speech this morning, the EU's chief negotiator Michel Barnier delivered a series of hard truths to the Brexiteers. "I have heard some people in the UK argue that one can leave the single market and keep all of its benefits - that is not possible," he said. "I have heard some people in the UK argue that one can leave the single market and build a customs union to achieve 'frictionless trade' - that is not possible." After backing down on the Brexit timetable, the UK will soon have to pay a sizeable divorce bill if it wishes to make further progress. The promised £350m a week for the NHS will gave way to c.€100bn for the EU.

The UK's economy, meanwhile, is showing signs of strain. GDP growth fell in the most recent quarter to 0.2 per cent, household income is falling at the fastest rate since 1976 (owing to the pound's post-referendum depreciation) and productivity growth is at its worst since the Napoleonic era. The British public, who, as Chancellor Philip Hammond has correctly noted, "did not vote to become poorer", are becoming just that. Not unrelatedly, a Survation poll showed 54 per cent would vote Remain in a second referendum, while just 46 per cent would vote Leave. Though they claim the backing of "the people", the Brexiteers become tellingly defensive when the possibility of consulting them again is floated. Labour's advance has made them newly fearful of public opinion.

The chances of Brexit being stopped are still small. Under Jeremy Corbyn's leadership, Labour will unambiguously back withdrawal, while the Tory Brexiteers are stronger and better-organised than their Remain counterparts. But more than at any time since the referendum, the Leavers are beginning to feel the wind turn against them.