Hats off to the Cabinet Minister who told this site in May that the Government would win a customs union vote.  “I think we can burn off a few of ours plus get a few Labour votes and, equally important, absentions,” he told us.  Yesterday’s victory makes a confidence vote in Theresa May less likely before the recess – the Commons rises next Tuesday – and gives Conservative MPs a chance to breathe, pause and think.  They should make the most of it.

For the fact remains that there is very unlikely to be a majority for the Prime Minister’s White Paper proposals in the Commons.  A lesson of the week is that while Remain-orientated rebels can sometimes defeat the Government (Phillip Lee beat it yesterday with his European Medicines Agency amendment), Leave-supporting ones have Ministers at their mercy.  That Brexiteering frog has leapt out of the boiling water, and has parked itself on their backs.  Were this not so, the Government whips would not have swallowed Monday’s ERG amendments.  And if those White Paper plans wouldn’t command a majority, nor would the watered-down version of them that the EU Commission and 27 are almost certain to insist on – at least without an even bigger Conservative revolt than over the White Paper ideas.  That would leave the Party on the verge of a split.

That leaves three possibilities for Tory MPs to chew over as they ponder the coming months.

First, Theresa May agrees a diluted variant of her proposals with the EU, either in the autumn or later, and gets them through the Commons with the aid of the Chris Leslies and Wes Streetings and Chuka Umunnas.  That would bring the party system to the verge of realignment.

Second, the Prime Minister brings such a deal to the Commons, and is defeated.

Third, there is no agreement with the EU at all.

In either of those last two cases, Ministers and backbenchers should ask themselves what the odds are, in those circumstances, of, at the one extreme, Brexit being postponed or cancelled altogether; or else, at the other, of a “Doomsday Brexit” in which shortages of medicine, food and fuel wreak havoc.

If they conclude that either or both possibilites are more likely than not, they have no alternative but to look for a Plan B.  Here is one.

The Government tears up Plan A, and seeks to park the UK in the EEA for, say, four years.  At the end of that period, the UK would trade with the EU on basic WTO terms, if a David Davis-style Canada Plus Plus Plus deal had not been agreed.  This would give Ministers more than enough time to put the necessary No Deal arrangements in place.  If these won’t be ready by next March, the reason is that Downing Street and the Treasury have assumed since at least last December that there will be a deal; that there will therefore be a transition or implementation period until March 2021, and that Britain, therefore, doesn’t need to be “Ready on Day One” on March 29 next year. This site, Charlie Elphicke and James Arnell have advised them endlessly to the contrary.

It goes without saying that this stopgap plan is not perfect, to put it mildly.  In our view, EEA membership wouldn’t honour the spirit of the referendum verdict.  But it would satisfy the letter.  It could offer a port in a storm.  The Government would be able to look voters in the eye and say that Brexit had been delivered: after all, the EEA counties are not EU members.  Britain would be out of the CAP and the CFP and the home and foreign affairs pillars.  A plus: the EEA three are not in the Customs Union.  Britain would have a latitude on trade deals that the White Paper plan does not deliver.  A big minus: the EEA requires free movement, unless that fabled “emergency brake” is applied.  We do not need to repeat our view of why such a brake is not a proper immigration policy.  But were we to join the EEA, we would have little alternative but to apply it – and face the prospect of retaliatory action.

It is a statement of the obvious that Theresa May could not deliver such a scheme.  It is not in the Conservative manifesto and she has ruled out EEA membership.  She would have to go.  Her replacement would need to be a convinced Brexiteer, since only such a person could persuade the public that the EEA was a resting-point in the Brexit journey, not its end.  He or she would ideally be uncontaminated by the Government’s bungled handling of leaving.  This new plan would almost certainly require a general election.  On this timetable, the UK would leave the EEA for WTO basic, if necessary, in 2023 – a year before an election in 2024.

Dominic Raab might qualify as the new Tory leader.  Boris Johnson would say that he has not been involved in drawing up the Government’s Brexit strategy, and is therefore uncontaminated by its failures.  Michael Gove and Penny Mordaunt, though leavers, support the White Paper.  Either would therefore have to persuade a sceptical public and party that they did not plan to make EEA membership permanent.  So would, say, Sajid Javid and Jeremy Hunt, as former Remainers.

ConservativeHome doesn’t need to be told that such a plan is very risky indeed.  Jeremy Corbyn might win that election. The Fixed Terms Act provisions might frustrate calling it in the first place.  The Commons has already voted against the EEA.  The EEA countries might not be willing to have us.  The EU might seek to obstruct what would in effect be a new EEA deal for Britain (we are of course an EEA member now).  Though a potential plus for the EU is that the EEA is a tried-and-tested arrangement, and it wants to dine table d’hote, not a la carte.

All in all, if Conservative MPs believe that no deal with the EU, or a deal that is defeated in the Commons, would be followed either by a Doomsday Brexit or by no Brexit at all, they can only conclude that the risks of gambling on this Plan B are less than the risks of sticking with Plan A and with the Prime Minister.  If they do, they could wait until September or perhaps later until acting – though they might look back then, and regret not moving decisively now.

It may well be that they decide instead that the Government and Parliament, in the event of No Deal, would not seek to postpone Article 50, and that the practicalities are manageable.  Jacob Rees-Mogg believes that the timetable, the passing of the withdrawal legislation, and government monopoly on moving legislation mean that a basic WTO settlement, or something like it, is the inevitable consequence if a deal is not agreed or is voted down.  If Tory MPs think he is right, and that No Deal catastrophe is no more grounded in reality than was the Millennium Bug, then they should roll the dice and take their chances on Plan A.

And if anyone has a better Plan B, we’d like to know what it is.