If Sue Gray’s report is bad enough (or even if it isn’t) there are now at least 54 Tory MPs ready to call a vote of no-confidence in Boris Johnson. His attempts to shore up his position are not going well and exposing the shallowness of his personal support. “If Nadine Dorries is your main cheerleader,” says one minister, “you really are sunk.” But he isn’t: not yet. The would-be mutineers are waiting for a reason. They need to work out not just what would follow, but how bad the fighting would be – and whether the party could survive it.

The old Tory omertà, whereby MPs bury their grievances and differences for the sake of party unity, is already collapsing and the damage has started. Did Gavin Williamson really say he’d refuse to build a school in Bury if its MP didn’t vote with the Government? Did the Tory chief whip really tell Nusrat Ghani that her “Muslimness” had been raised as a problem in Downing Street? These are serious – and grim – allegations that voters may not forget in a hurry.

What Theresa May once called the “nasty party” seems to be making a comeback. Tory whips are being accused of bullying, which may sound like accusing a boxer of fighting. While most governments have whips who represent all wings of the party – using flattery as well as threats – No 10 only chose Johnson loyalists who had a weakness for bluntness. This led to plenty of resentment, much of which may soon come out.

Margaret Thatcher had the wets and dries, Cameron had modernisers and traditionalists, and Johnson had Brexiteers and Remainers. His unusual means of dealing with this was to fire all 21 of them by withdrawing the whip. This pained him, but he’d justify this to colleagues by comparing it to the purges of Augustus Caesar: brutal but bringing years of peace. The flaw in his analogy was that they also meant dictatorship.

Most Tory leaders make a show of party unity in their Cabinet choices, but Johnson has filled his team with those who backed him in the leadership contest. “He never even tried to be the unity candidate,” says one exiled ex-Cabinet member. “He has run a factionalist government, so divisions have grown.”

The Red Wall MPs provided the Tories with their majority and some talk of themselves as a new guard coming in to refresh the old party’s blood, creating a new, genuinely One-Nation conservatism. Liz Truss is generally seen as the champion of the new intake, but her problem may be how she promises low taxes – likely to be her signature theme – while supporting the high-spending policies that Johnson has sold.

This is a common Southern Tory complaint: that the Red Wall MPs like high spending and low taxes, and won’t accept the contradiction. “You talk to these guys and do a double-take,” says one Tory. “They always want more spending. You think: what party do you think you’re in?” They might respond: Boris Johnson’s party, and the mandate he personally won richly entitles him to push through his own blend of higher-tax, high-spend Toryism. One of the many arguments that would be played out in a leadership campaign.

Even among the low-tax Tories there’s a split, embodied in the row between Liz Truss and Rishi Sunak over the impending National Insurance increase. In a Cabinet meeting, Truss said the party should honour its manifesto pledge not raise taxes and let borrowing take the strain. This led to quite a fiery response from Sunak, who told her such an approach was fundamentally un-Conservative. This marks a Tory dividing line that runs far deeper than is commonly understood.

One of Sunak’s most strongly held political beliefs is that serious spending commitments must be funded (via tax or cuts) rather than dumped on the next generation via national debt. This is why he’s for the National Insurance rise: he thinks it holds up a mirror to the decision to spend all of the extra money. This model could be taken further, so all extra NHS spending is funded by increasing what would, in effect, become a special NHS tax – thereby focusing Tory minds next time they want to shower the health service with cash.

Should it come down to Truss vs Sunak, this would be a main debating point. She might be joined by Kwasi Kwarteng, Iain Duncan Smith and others offering lower taxes to party members and being relaxed about paying for this with a deeper deficit. It would all work out eventually, they’d argue, because lower taxes tend to mean more growth and, ergo, higher revenue. Sunak and others would argue that this is economic vandalism, more Reaganite than Thatcherite. It’s a very Tory argument, recited in David Davis vs David Cameron in 2005, but passions do run deep.

Then we have the more enthusiastic Brexiteers, dismayed that so little has been done with Brexit powers (David Frost quit the Government over this point) and keen to suspend the Northern Ireland Protocol rather than see more sovereignty eroded. Then Scotland: almost every single Tory in Holyrood has come out against Johnson, and at least some of these rebels have flirted, in the past, with the idea of breaking away from the “London Tories”. Such tension is a 
bad look for the supposed party of 
the union.

So we have a recipe for multi-dimensional Tory wars: high spenders vs the frugal, Scots vs English, Northerners vs Southerners, Brexit radicals vs incrementalists, free traders vs protectionists. All fought, quite plausibly, with a toolkit of dirty tricks. The “Partygate” scandals so far emanate from just one building: 10 Downing Street. Might similar soirées have been held in other government departments? If rule-bending activity in lockdown is enough to end political careers, there may be a few more ministers worried about what may come out.

Perhaps this is why some of Johnson’s allies are saying that his enemies can forget about any smooth transition. That he’d hang on to the last, maximising the agony, then there would probably have to be a snap election. Do they really want all that now? Après moi, le déluge: hardly the most optimistic message to keep his party together. But over the next tense few days, it might be the best he has.