A year ago, 53 Conservative MPs voted against Boris Johnson’s tiering plan – the biggest backbench Covid rebellion until yesterday.  The final figure is disputed but over a hundred of them opposed his Covid passport scheme, if tellers are included.

Tory leftists, Tory rightists, former Ministers, the usual suspects, previous loyalists, May supporters, ex-whips and, yes, Red Wallers joined together: the revolt defied faction.  Some were opposed to the Prime Minister’s plan in principle.  Others felt it was incoherent in practice.  Others still believe that the case for it has not yet been made.

Do not believe for a moment, however, that all of them voted on the issues alone – be they passports, masks or vaccination for NHS workers.  It is impossible to believe other than that some wanted to send the Prime Minister a message about his style of government, and their lack of trust in him.

Before the vote, some of them cheered him at a 1922 committee meeting.  And after the meeting, they eventually went into the No lobby to oppose him.  He had spent much of the day making his case personally to potential rebels.  It’s claimed that the whips believed the revolt was retreating.

Johnson is thus personally rebuffed and in perilous territory.  That message of discontent from some backbenchers is a declaration of intent from a slice of them – who knows how many?  They are readying themselves to send letters to Graham Brady demanding a vote of no confidence in their leader. Some will have written already.

The Prime Minister is fortunate in that Parliament breaks for the Christmas recess on Thursday.  So most Conservative MPs will not be at Westminster in the aftermath of that evening’s by-election result from North Shropshire.

In the New Year, we will know more about Simon Case’s investigation into Downing Street and other social events during lockdown, and what Christopher Geidt, Johnson’s adviser on ministerial interests, has to say about the Number Ten flat redecoration controversy (assuming he doesn’t become the second holder of the post to resign).

The Parliamentary Commissioner for Standards, Kathryn Stone, is likely to pitch into the latter , in the wake of the upholding of her judgement on Owen Paterson.  All these development would present the next likely moments of risk for the Prime Minister were it not for Omicron.  Let me explain how the variant potentially speeds matters up.

In the ideal world that doesn’t exist, MPs wouldn’t vote on any future restrictions until it was clear whether or not the new Covid variant was going to produce enough staff shortages and patient admissions to make some hospitals effectively inoperable.

Either this would be happening by the time of the next vote, in which case a big chunk of yesterday’s rebels would back the Government, as agitated e-mails, tweets and phone calls poured in from constituents… (It is unlikely amidst such a sense of national crisis that Graham Brady would receive enough letters to trigger a no confidence ballot.)

…Or else it would be evident that Omicron won’t produce enough admissions and shortages to leave a mass of patients marooned in ambulances outside A & E departments, or waiting on trolleys in hospital corridors as wards fill up – as MPs who opposed restrictions are targeted on social media.

In such an instance, Johnson would presumably claim that yesterday’s package had worked; his backbench opponents would doubtless claim that it was never needed in the first place.  At any rate, there would be no mood of national crisis, so more of those letters to Sir Graham would probably be sent.

At which point, let’s return to the real world – one in which a further set of restrictions may be proposed by the Government before the scale of the challenge posed by Omicron to the NHS is clear.  Such measures are likely to be announced before the New Year.  The Prime Minister has reportedly promised a vote on them.

In such circumstances, we might well see yesterday revisited: namely, Johnson reliant on an unspoken alliance with Labour to push new restrictions through, with a majority of Tory backbenchers voting against his new plans.  I say yesterday revisited, but the internal Conservative debate may well be even more acrimonious a second time round.

In short, the Prime Minister may well soon have to choose between what he sees as his duty to the country and the view of his party, or at least a majority of it on the backbenches.  The easiest course to take would be the path of least resistance: in other words, for Johnson to drop his planned new measures.

But what happens then if Omicron does turn out temporarily to overwhelm the NHS?  Or, perhaps more credibly, if there’s an “NHS crisis” anyway next month, as flu, the backlog of treatments and operations, and Covid all combine to force one, and Labour simply blames it on Omicron – and the Government?

How low do the Prime Minister’s poll ratings plunge then, not to mention the Conservatives’?  What if resignations come from Ministers who believe that new restrictions are essential, not from those who think they’re unnecessary?  Or from both?  In such circumstances, might Sir Graham not receive enough letters to force a ballot?

It is impossible to contemplate the future without grasping that Tory MPs also face a choice.  Is a majority of backbenchers now determined to vote against major new restrictions come what may?  Have they come to view those who warn of a collapsed NHS as just so many boys crying wolf?

I understand why many of yesterday’s Conservative rebels believe so – or think at any rate that the case for vaccine passports hasn’t been proved.  Nonetheless, the landscape may look very different in a week or so.  After all, the point of the fable is that the wolf eventually turned up.