Brexit has never been deliverable under the terms that were promised. For more than two years, its political champions have sought to evade and disguise this reality. On 11 July 2016, David Davis, the Brexit Secretary, wrote that the UK could “negotiate a free trade area massively larger than the EU” by 2018. As recently as 20 July 2017, Liam Fox, the International Trade Secretary, predicted that a new British trade deal with the EU would be “one of the easiest in human history”.

The collision with reality has been painful. Britain has been forced to agree to a £35-39bn “divorce bill” and to a 21-month transition period (during which it will abide by all EU laws, including on trade and free movement). The higher NHS spending promised by Theresa May will not be funded by an illusory “Brexit dividend” but by tax rises.

In spite of these reversals, the Brexiteers have maintained that it will be possible for the UK to leave the single market and the customs union without imposing economic harm and without creating a hard Irish border. As these promises have proved irreconcilable, Tory Leavers have blamed everyone but themselves: the media, the House of Lords, the judiciary, the civil service and the Prime Minister.

On 2 July, Jacob Rees-Mogg, the leader of the Conservatives’ hard Brexit wing, issued one of his periodic threats to Mrs May. In a column for the Daily Telegraph, he invoked the fate of the former Conservative prime minister Robert Peel, who was forced to resign in 1846 after splitting his party over the repeal of the Corn Laws. Should Mrs May fail to uphold the “righteous cause” of Brexit, it was implied, she would be similarly ousted.

After Tory MPs condemned Mr Rees-Mogg for his arrogance, Boris Johnson defended his colleague as “principled and dedicated” (qualities to which the opportunistic and truculent Foreign Secretary is a stranger). Mr Rees-Mogg is, at least, unfailingly wrong. The historical analogy he drew diminished, rather than exalted, his cause.

Mr Peel is rightly revered as a prime minister who put country before party. While most Tory MPs favoured the Corn Laws (tariffs on imported food and grain), which ensured lucrative profits for landowners, free traders demanded their repeal to protect the poor and, most urgently, to alleviate the Irish famine. As Mr Rees-Mogg himself concedes, “it was a policy that worked”. Yet he nevertheless maintains that Mrs May should support an unworkable one. Were the Prime Minister to oppose a hard Brexit, she would certainly split her party – but she would also protect the economy and living standards.

This is not to diminish, as some do, the EU's profound flaws. It has been too opaque in its decision-making, too austere in its fiscal policy and too remote from its citizens. Yet as the UK is now discovering, there are worse alternatives to membership of an imperfect – but necessary – institution.

The Brexiteers conjured up an image of a cost-free utopia that does not exist. As this illusion unravels, the blame resides solely with them.