BORIS Johnson has tonight suffered not just the resignation of his most important minister, the Chancellor of the Exchequer, Rishi Sunak, but also that of a former Chancellor, Sajid Javid. It only took one, Sir Geoffrey Howe, to destroy Margaret Thatcher back in 1990. She was one of the Tory Party’s most successful leaders, too.

Surely the time is up now for Johnson. The “greased piglet”, as he was described by his predecessor, David Cameron, has finally been caught. But has he? Is the grip firm enough? Could he yet wriggle free?

As a sweaty Westminster waited last night for more resignations to follow Sunak and the Health Secretary, Javid, no-one was quite willing to state the obvious: that no prime minister can shrug off a rebellion on this scale. Certainly not the Tory leader of the House, Jacob Rees-Mogg.

Rees-Mogg strode magisterially into the TV studios insisting that the Prime Minister had no need to consider his position, that the departed ministers were “eminently replaceable” and that the PM had his own “mandate” from the 2019 general election.

The Mogg cited cases of Prime Ministers, right back to Lord Salisbury in the 19th century, losing substantial chunks of their cabinets and carrying on regardless. The Culture Secretary, Nadine Dorries, and the Deputy Prime Minister, Dominic Raab, led the cabinet loyalist in declaring their continuing faith in Johnson.

But the truth is that Johnson’s authority, never very great, is completely destroyed. The discontent on the backbenches is fulminating. The Tory MP Andrew Bridgen forecast that Johnson would be out of office before the summer recess.

Of the two resignation letters, Sunak’s is the more intriguing. He makes clear not only that he was appalled by the Prime Minister’s lack of integrity, but also that he had profound concerns over the management of the economy and his stewardship of the nation’s finances.

Sunak is clearly fed up with the please-everyone, spendthrift policies favoured by his boss. “Our people know”, he wrote,” that if something is too good to be true it isn’t true”. It appears that the recent £31billion cost-of-living giveaway was the last such policy that this fiscally conservative Chancellor could thole.

“Difficult decisions” needed to be taken - a reference, presumably, to the National Insurance increases that many Tory MPs want reversed. “I firmly believe the public are ready to hear that truth”,Sunak went on, concluding that could not go ahead with the scheduled joint statement on the economy with Johnson next week. That is about as damaging a condemnation of a Prime Minister as it is possible for a Chancellor to make.

The proximate cause of this latest leadership crisis was the latest sexual harassment scandal to hit Westminster. The former top civil servant, Lord McDonald, revealed that Boris Johnson had been Told about the allegations of sexual misconduct levelled at the disgraced deputy chief whip, Chris Pincher. It was hardly a surprise.

“Pincher by name, Pincher by nature” is what Johnson is reputed to have remarked about his behaviour. The PM claimed that he had simply forgotten about being told about Pincher’s behaviour, which sounds so implausible that it may even be true. He is not a details man.

But it hardly matters. After Partygate, tractor porn and numerous sexual harassment cases it was just all too much. Javid, who had resigned before as Chancellor in 2020 over Dominic Cummings's machinations with his staff, made clear that it was the Prime Minister’s conduct and personal lack of integrity that made it impossible for him to continue as Health Secretary. “The country needs a strong and principled a Conservative Party”, he wrote, "and the Party is bigger than any one individual”.

So what happens now? Neither of the resignees appeared to be making a bid for the Tory leadership. Indeed, Sunak said he didn’t expect another cabinet post, which suggests he will be off to California and Silicon Valley whence he came.

A poll by the website Conservative Home this week revealed that the only declared contender for the battered Tory crown, Jeremy Hunt, would lose against any of the present cabinet. There is a serious chance, according to this poll, that the Defence Secretary, Ben Wallace, could end up as a caretaker leader and Prime Minister. For those who remember his service as a relatively obscure MSP in the Scottish Parliament twenty-odd years ago, that might come as a shock.

But politics is all about being in the right place at the right time, and right now the Conservatives are all over the place as Johnson’s crazy thrill-ride comes to a sticky end.