Allegra Stratton, the former Number 10 press spokesman who resigned tearfully last week, never looked quite right for the job. A Cambridge-educated intellectual with an artsy background – she was named after the daughter of Lord Byron – Ms Stratton wasn’t a typical Tory. She spent most of her career at The Guardian and the BBC. But you couldn’t help feeling that Ms Stratton was badly treated. Sacrificial lambs never looked so meek.

Someone in or close to Number 10 leaked a video of her making light of questions about the party-that-wasn’t-a-party in Number 10 last December. It was merely a dress rehearsal for a press conference that never took place. Indeed, she was moved to another role shortly afterwards. Ms Stratton will at least have a place in history as Boris Johnson’s press spokesman who never actually spoke, yet wrecked his administration.

But the Government is not going to fall over this, at least not over Christmas parties. Boris Johnson has far worse problems ahead. He faces his worst backbench rebellion this week over vaccine passports, the loss of a crucial North Shropshire by-election, and censure for misleading the standards adviser, Lord Geidt over the funding of the redecoration of his Number 10 flat. Not even this Teflon-coated father of seven, after his latest issue, can endure such attrition indefinitely. Labour now has a sustained lead in opinion polls.

The public are furious that there appears to be one rule for Number 10 and another for them. However, Boris Johnson was not personally involved in the infamous party and it remains a disciplinary matter for the civil service. The Cabinet Secretary, Simon Case, is conducting the inevitable inquiry, designed of course to sweep the story from the news pages. Yet no-one is really in any doubt what happened.

Press officers, civil servants and political advisers were working late on December 18, 2020. They were preparing for Boris Johnson’s announcement the next day about the impact of the Kent variant (remember that?) on Christmas lockdown. A staffer was sent to the local Tesco above Westminster Underground station for some cheese and wine. There followed a kind of working party, if you’ll excuse the pun, at which Secret Santa gifts were exchanged and speeches made.

Was this breaking the law? There was an element of pre-planning, with people reportedly invited via WhatsApp. But all of the attendees were working legitimately in Number 10 as essential workers and were taking daily lateral flow tests. People are allowed to eat and hold meetings during lockdown, and while this led, in some accounts, to late-night imbibing it is just possible to claim that no actual Covid rules were broken. The spirit of the rules were breached, but arguably only through an excess of Christmas spirit.

Other parties are, of course, available, including one in Conservative Central Office that sounds positively bacchanalian. Dominic Cummings, the disgraced former chief adviser to Boris Johnson, has been blogging and tweeting about others involving Government servants and the PM. But the media can only handle one scandal at a time and Johnson should weather partygate.

What could bring Johnson down, and partly explains the air of crisis in the Government, is the animosity, bordering on loathing, that many Conservative MPs now feel for their leader. Tory papers like the Daily Mail and The Daily Telegraph are withering in their scorn.

You would never believe reading these pages, reflecting as they do the views of backbench Tory MPs, that Johnson not only delivered Brexit but won a historic landslide victory two years ago. They treat him like an alien.

Why? It is partly his chaotic style, his casual association with the truth and his jokey bumptiousness. But it is more than that. After all, no-one could have been in any doubt about Boris Johnson’s dodgy integrity. He was sacked from the Daily Telegraph for lying and again from a junior ministerial post for being fast and loose with the actualite. He is essentially a showman – a gifted journalist with a witty turn of phrase. He was never a details man.

After the meticulous drudge Theresa May, Tories had had enough of micro-managers. They wanted someone with Churchillian flair. What they didn’t want, and what came as a genuine shock, was to discover that not only is he not Winston Churchill, Boris Johnson isn’t really a Tory. They were just about prepared to accept the increased role of the state during the pandemic, but what Tories cannot thole is what they regard as Johnson’s addiction to public spending.

This Tory PM has raised taxes to their highest level since the 1950s. He is spending over 40 per cent of all public service spending on the NHS, which most Tories believe is a financial black hole. Businesses have been hit by a double whammy. He’s ramped up corporation tax to 25%, reneging on promises by previous Tory Chancellors to cut business taxes. The increase in employers’ National Insurance in the Budget hit many businesses hard just they were having to increase wages because of the

post-Brexit labour shortage.

This was why Johnson’s Peppa Pig speech to CBI bosses last month was such a disaster. When he wasn’t actually losing his place, the PM recycled his COP26 lecture about climate change with added waffle and jokes. Business leaders accept that net zero is a good thing, but suspect they’ll be paying for it. They believe that public spending on the NHS is only possible because they generate the wealth and taxes that finance it. Hostility to taxation is so ingrained in Tory thinking that it is almost an article of faith.

There is a mirror image here of what happened to Labour after Jeremy Corbyn took over as leader in 2015. Many Labour MPs were simply embarrassed by him and loathed his leftist cliches. The Shadow Cabinet staged a mass resignation – called the “chicken coup”. It failed because there was no credible successor to Corbyn, and because he had strong backing from a well-organised left.

Johnson will also survive pro tem because there is again no credible successor, despite premature talk of Rishi Sunak and Liz Truss being “on manoevres”.

But he doesn’t have much grass-roots support – at least not any more. The joke has turned sour. Tory leaders are supposed to be sober, responsible men of substance and vision. People vote for them because they are good at managing the economy and don’t rack up unpayable public debts.

Right now, public debt is higher than it has ever been at nearly 100% of GDP. In 2007, under Labour’s Gordon Brown, it was 36%. Economic growth, following an initial spurt after lockdown, has ground almost to a halt. The latest semi-lockdown over Omicron has been the final straw for many Tories, who think it will wreck the recovery altogether.

Many Conservative MPs regard vaccine passports as totalitarian invasion of personal liberty. Why, they say, did we vote for Brexit only to get a European-style big state with even more regulation and higher taxes? Nor do they fully share the PM’s green agenda, which they think is naïve.

Boris Johnson is now finding himself in a culture war with his own party. There can be only one winner.