Do you remember when the prospect of a no-deal Brexit was supposedly so remote that it was scarcely worth discussing in advance of the referendum? “The day after we vote to leave,” Michael Gove said in April 2016, “we hold all the cards and we can choose the path we want.”

As Theresa May began her negotiations with the European Union, no deal next became a theoretical possibility that had to be “kept on the table” as part of the poker game. As Boris Johnson told the Commons in July 2017: “There is no plan for no deal, because we’re going to get a great deal.”

Then, during the Conservative leadership contest, Johnson declared that the chances of leaving the EU without an agreement were “a million to one against” – Bullingdonese for “quite likely, I suppose, but I do wish you’d stop asking”.

Now, at last, we have entered a quite different strategic and doctrinal zone, in which no deal is presented not only as an outcome that is endurable, but – for many Brexiteers – positively desirable. They contemplate the prospect of a “clean” exit not with a sense of impending collective failure, but the millenarian zeal of a religious cult on the verge, at last, of reaching the hill upon which they will build a new Jerusalem (while feasting on chlorinated chicken sandwiches).

To squeeze in an election before Brexit day would require a vote of no confidence as soon as the Commons returned

In Johnson’s pledge that the UK will leave on 31 October, “no ifs or buts”, there is at least a bracing clarity. We know, finally, what we are dealing with: a prime minister, aided by the reassembled Vote Leave campaign masquerading as a government, who will do absolutely anything to achieve this primary and defining objective.

What might his methods include? I do not believe that the prime minister and his team are as enthusiastic as some suggest about an early autumn election. That said, Johnson is throwing cash about like a politician preparing for electoral battle – witness the £2bn boost for the NHS he announced in the Sunday Times. And the Friday meetings in Downing Street chaired by his de facto chief of staff, Dominic Cummings, clearly have a focus and ferocity consistent with preparations to go to the country.

He is reportedly confident that he can neutralise Nigel Farage’s Brexit party, and it is certainly true that the need for a separate provisional wing of the pro-leave movement is now much less obvious than it was under May.

But Johnson and his team also know that Labour, frozen in aspic under Jeremy Corbyn, may now have reached its moment of maximum vulnerability. Cummings is said to believe that the Liberal Democrats, resurgent and unambiguously pro-remain, will eat disproportionately into Labour’s vote, to the net benefit of the Tories. On Sky News’s Sophy Ridge on Sunday, James Cleverly, the Tory chairman, conspicuously declined to rule out a general election.

Let us say, in any case, that the choice is not in No 10’s hands. When parliament returns on 3 September, the government will certainly face a vote of no confidence if it is still on course for a no-deal Brexit. After last week’s byelection in Brecon and Radnorshire, Johnson’s majority – which, never forget, depends upon the tetchy support of the Democratic Unionists – has been sliced to one.

Bear with me on the technicalities: under the Fixed-term Parliaments Act 2011, a vote of no confidence in the government would trigger a two-week scramble to form a new administration. If that quest failed – as it would – an election would be triggered. The Electoral Registration and Administration Act 2013 requires 25 working days between the dissolution of parliament and polling day. To squeeze in an election before Brexit day would require a vote of no confidence as soon as the Commons returned; the pre-emptive cancellation of the party conferences; a fortnight of pointless attempts to form an alternative government ending on, say, 17 September; and a snap election held after the minimum five-week campaign on Thursday, 24 October. Johnson wins, and Britain leaves a week later.

How likely is it that this precise sequence will fall into place? How often does politics observe such neat patterns? It is more likely, indeed, that 31 October could fall in the middle of an election campaign – or even (since it is a Thursday) on polling day itself.

No-deal Brexit can still be averted, Labour says Read more

Geoffrey Cox, the attorney general, believes there is no legal impediment to the UK leaving Europe even as rosette-bearing politicians crisscross the nation in battle buses. Mark Sedwill, the cabinet secretary, reportedly dissents from this opinion, on the grounds that convention precludes ministers from taking any “major policy decisions” in the prelude to an election. To which Cox would reply: the decision was taken by the British people in June 2016 and the legislation to implement that decision is already in place.

Already, the pro-remain campaigner Gina Miller is investigating the potential for a judicial review of this grotesque possibility. For how odd would it be for an election about Brexit, triggered by a confidence vote caused by Brexit, and framed by the prime minister’s readiness to embrace a no-deal Brexit, to be made both redundant and ridiculous in real time by Brexit happening anyway, in the thick of electoral battle?

One might ask, more pithily: how the hell did we get here? Yet such are the times in which we live, and such are the worse ones towards which we are heading.

• Matthew d’Ancona is a Guardian columnist