Boris Johnson’s vantage is commanding.  His party has a Commons majority of 79.  Labour has still not gained a clear poll lead. The last four by-elections suggest that the left remains divided and the right united – until or unless the Reform Party, or something like it, takes off.

Johnson himself is integral to that position.  Had Theresa May remained Prime Minister, the Conservatives would not have “got Brexit done”, and the Red Wall would still be Labour.  Johnson reaches parts of the electorate that other Tories don’t reach.

So why is that it is suddenly more likely than not that another Conservative MP will lead his party into the next election?  Very simply, because while Tory MPs will tolerate a leader who is not “on your side”, at least for a while, their patience with one who isn’t on theirs, as they see it, is very limited indeed.

The fate of the Government’s housing plans was a sign that a majority of the best part of a hundred is not what it was.  The patience of the Parliamentary Party is fractured by short-term developments, such as the strain that lockdown put on party management, and longer-term ones, like the death of the post-war culture of reflexive loyalty.

The challenges confronting the Government are formidable: managing Brexit, Covid, and the threat of an economy undone by unsustainable spending, debt and taxes.  And this morning, there comes evidence that Labour may be working its way back, for all of Keir Starmer’s lack of inspiration, to that traditional mid-term polling advantage

Such leads can go as suddenly as they come. What would make that less likely is a breaking of the magical bond between Johnson and voters (or enough of them, at any rate, to maintain his party’s dominance).  To date, the old charge that it’s one law for politicians, and another for the rest of us, hasn’t stuck to him.  Will it do so now?

Barnard Castle dented Johnson’s Teflon.  The Matt Hancock saga would have inflicted further damage had the former Health Secretary not resigned himself.  The saga of the Downing Street parties may be third time unlucky.  It hits many people where it hurts.

I don’t need to stress the point that Covid has seen a mass of job losses, squeezed incomes, and harrowing deaths: if the virus itself has been especially rampant among older people, its effects have been particuarly damaging on younger ones, especially among those who can’t work from home and aren’t in public sector employment.

The furious e-mails from constituents who aren’t simply the usual suspects is one thing.  The possibility that they may be sustained is another.  What will keep it going is the likelihood of new revelations, the confidence of Parliament’s new regulator class in the wake of the Owen Paterson debacle, and potential police action.

Plus the probability that Ministers’ authority to manage Covid restrictions is shot.  Furthermore, Johnson, unlike Margaret Thatcher, has no reliable bedrock of media support, not even at his “real employer” – the Daily Telegraph.  The support of this website isn’t remotely enough to sustain him.  And for what it’s worth, he can’t take it for granted.

How many parties during lockdown took place at Downing Street or maybe Chequers – let alone elsewhere in government offices or Ministers’ homes?  Who was there?  Why won’t they follow Allegra Stratton’s lead – and resign?  What will Tory MPs do when Labour start tabling Commons motions demanding that they do?

What will worry them most is a growing view that Number Ten can’t stick to anything and doesn’t tell the truth – not so much to voters (which I’m afraid they will take more or less for granted), but to them, whether the matter to hand is Downing Street wallpaper, parties, Afghan dogs, Paterson, “buyer’s remorse” or the football Superleague.

A different kind of Prime Minister might be able to offer the usual sort of evasion tactics: reshuffle the Cabinet, change the Number Ten team, relaunch the Government.  But Johnson isn’t that kind of conventional politician.  His problem isn’t Dan Rosenfield.  Or Simon Case.  Or Ben Gascoigne.  Or others who most voters have never heard of.

Or the Cabinet, come to that.  No: Boris Johnson’s problem is Boris Johnson.  To which Dominic Cummings is adding a subversive coda: Boris Johnson’s problem – according to his enraged, insightful, self-interested, destructive and obsessive former chief adviser – is Carrie Johnson.

Cummings has been painting a picture since leaving government, mostly via Twitter and substack, of Number Ten as a kind of latter-day Versailles, with the Prime Minister cast as a weak Louis XVI, who will do almost anything to placate a volatile spouse, and his wife as a modern-day Marie Antoinette.

Whether the row to hand touches animals, wallpaper, holidays, parties, advisers or almost anything else, Cummings has a way of popping up to tell anyone willing to listen that Carrie Johnson is to blame.  I scarcely need to add that he is not a disinterested witness.  And that he has a willing audience of institutional sexists.

But most Tory MPs don’t fall into that category, whatever you may read in the papers, and are rational actors (at least most of the time).  They are looking closely at a leader who, within fewer than 24 months, has divorced, remarried, nearly died, had a child – and whose life, never tidy at the calmest of times, has seen a lot of change.

Chaos is a gaping pit waiting to swallow us all, a horrified Varys exclaims in Game of Thrones.  No, replies Littlefinger: chaos is a ladder.  And though a few Conservative MPs think that they’re Littlefingers, most of them are actually Varyses, in instinct if not character: they want calm, order – and re-election.

If chaos really is a ladder, Johnson has certainly climbed it.  But the Parliamentary Party has an itch for convention that it is persistently tempted to scratch.  It sees before it a government which is doing many good things, a few bad ones, and is under attack from bits of Britain’s scattered Remain Ascendancy in Britain’s institutions.

I’m in danger of deploying Game of Thrones analogies to exhaustion and beyond, but there is a danger that Tory MPs will come to see Johnson if not as Littlefinger, then as a sort of real world Robert Baratheon, who is letting the kingdom slide while he parties his life away.

That would be to underestimate the Prime Minister’s endurance, cunning, survivability – and, yes, his work rate.  Furthermore, there is no replacement available with proven Heineken appeal.  The bottom line is that the last election result gave Johnson a mandate which endures.

I’m not in favour of regicide, which would threaten the kind of bitterness that consumed the party, after it deposed Margaret Thatcher, for a generation.  And a Sunak or Truss leadership, say, would lack legitimacy with the electorate – in terms of electoral validation, anyway.

Nearly always, the best course to take in life is to keep calm and carry on.  To which some will answer: carry on where – to Johnson being washed out by a tide of investigations, revelations and inquiries?  And a few, taking their cue from Cummings: Carrie on with whom?

They will say, doubtless correctly, that the Cabinet will cower rather than try to force an internal restructuring that wouldn’t work anyway.  The least bad course now for Johnson would be to fling open the doors and let the investigators in – to sift all the evidence and claims.  But even his friends may not be able to save him from himself.