Mealy-mouthed protestations by the Johnson camp that he and his followers do not want to unseat Mrs May simply won’t wash. Nor will the defiant stance taken by Number 10 in response, with the familiar platitudes about “serious leadership”. This is the beginning of the end for her premiership. Johnson’s condemnation of her Brexit blueprint as handing “victory” to the EU, “waving the white flag” and leaving Britain with “diddly squat” could hardly have been a more explicit pitch to be Tory leader.
It has been clear throughout his entire career that Johnson believes he has some sort of divine right to be Prime Minister. For him, it has never been a matter of “if”, simply a question of “when”. No matter that his dismal record in office, most recently as one of the worst foreign secretaries of any party in living memory, should disqualify him from getting anywhere near 10 Downing Street, nor that he is poison to large parts of the electorate.
Poison, too, to a substantial element of his own party, with the former attorney-general, Dominic Grieve, already on record as saying he would not serve under Johnson. It might be different if he, or any of his fellow hard-line Brexiteers, had some sort of coherent plan for leaving the EU, but they don’t.
Johnson is the worst sort of politician – the type that only knows how to wreak destruction in pursuit of personal ambition, with no skill for building consensus or setting a clear direction.
There can be no question that he knew exactly how destructive yesterday’s attack on Mrs May would prove, or that his supporters will encourage his leadership ambitions.
But if he somehow achieves his goal, Johnson is going to find it a Pyrrhic victory, because the Tory party is all but ungovernable, mostly as a result of his own malign influence.
Festering discontent over decades about Britain’s relationship with Europe, and the bitterness that the Brexit debate has wrought – much of which is directly attributable to Johnson – has rendered the Conservatives incapable of setting a clear direction of travel that a majority of its MPs can back.
They can replace Mrs May, and hand Johnson the prize he has so long coveted, but it won’t make any practical difference. The arguments and enmities will still exist, just in a different form.
And meanwhile the country drifts towards Brexit, without proper direction, despite the dire warnings of business that it will cause huge economic damage without a sensible deal being struck with the EU.
Mrs May can’t have regarded today’s return of Parliament after the summer recess with anything other than trepidation.
The next few weeks were always going to be torrid, with the Conservative conference looming, as well as next month’s crunch meeting of the European Council at which a Brexit deal is due to be struck.
Against a backdrop of reports that Ukip supporters are infiltrating local Conservative associations to push for a hard Brexit, and a lukewarm response by the EU to the Prime Minister’s Chequers plan for leaving, things were already formidably difficult for her.
It is a measure of Johnson’s ruthlessness that he chose to stick the knife in at a moment when things could hardly be worse for his party, or for the Government of which he was so recently a member.
Nobody sensible would now bet on the survival of Mrs May as Tory leader beyond the next few difficult weeks, and if she is toppled, a general election must surely follow because the Government’s credibility will be completely shredded.
The country cannot accept Boris Johnson being installed as premier by a cabal of his supporters at a time when the most important political negotiation since the Second World War is in such disarray.
Only the electorate can decide who is fit to lead the country under these extraordinary circumstances – and it may yet be that the scale of the mess is such there will be a growing public clamour for a second referendum to decide on the form Brexit should take, or if it should happen at all.
Yesterday was about Boris Johnson casting himself as not just the saviour of the Tories, but of the mythical vision of Brexit he sold in the referendum campaign two years ago. His party should be wary of such hubris. Instead of its saviour, he might well be the man who causes it to crash out of office.