Let’s assume this really is the start of the last act of Theresa May’s premiership. Let’s assume too that her Withdrawal Agreement dies a fourth and final death in the Commons in early June. The Conservatives will then go looking for a new leader and prime minister. There are already no end of candidates.

But I have a question: why would anyone want the job in those circumstances?

If the WA dies, there are only two options left for Britain: leave with no deal on October 31, or revoke Article 50. Anyone who tells you there is a third option is trying to sell you something.

Yes, I know that various people suggest that a better form of exit deal is possible. It’s not.

Nor will the EU27 easily extend again after October for a Conservative PM seeking to change or improve the WA. Why would they? What confidence could they have that any such deal would pass the Commons?

But let’s say they do. Let’s say Angela Merkel somehow summons up the strength and willingness to bend the 27 to her will again and grant one more last chance. Could a new Tory PM survive the decision to accept that fresh delay?

No, for May’s successor, Brexit will be a binary choice: no deal or no exit. The first choice crashes the UK economy and dooms the Conservatives just as Black Wednesday did. The second averts economic disaster but breaks a fragile party. Either choice dooms and defines your premiership.

Of course, anyone who genuinely believes they can be PM must also believe they are a man or woman of destiny, the sort of person who can change history and cheat the odds. Maybe one of our would-be leaders can see a third and better option if the May deal dies. And maybe they’ll be right.

But right now, to this mere mortal, it’s impossible to avoid the conclusion that if May and her deal do indeed fall next month, the premiership of the Conservative who follows her will be even shorter and more painful than hers.