Time is running out for Theresa May – she cannot survive another Commons rebellion

She will be fortunate to gather enough support from her own backbenchers even to have something to offer the EU

As a thought experiment, imagine for a moment that the House of Commons passed a bill to repeal the laws of gravity, and ordered the prime minister to go away and implement it. Would she then float gracefully away, leading a proud global Britain into a new, anti-gravitational world of its own? Or would the “will of parliament” itself honouring a vote of the British people to “leave gravity” soon discover the limits of its powers, and return to earth with a great big thump?

The proposed abolition of the Irish backstop in the supposedly completed UK-EU withdrawal agreement is not something rooted in the certainties of Newtonian physics; but neither is it a matter of “negotiation” in the usual sense that there is some middle, or common, ground, where some give and take on both sides can see things “over the line”, as in talks between employers and unions about a pay rise.

The Irish backstop is required because no one has yet come up with a logical, practical method for a country to be outside a customs union next door, and yet to have no controls on the border. It is a simple impossibility.

If and when the technology becomes available to square this particular circle, then the backstop will indeed be unnecessary, and the row about it would dissolve, as the current treaty envisages. But no such solutions have been discovered. The Leavers’ anxiety to win a “freedom clause” allowing Britain just to forget about solving the logical dilemma in a few years’ time suggests that they too have little hope of such technologies being invented.

Theresa May, if all goes well for her – and this seems increasingly unlikely – will soon be able to go to Brussels, Dublin, Paris, the Hague, Berlin and anywhere she fancies, armed with a demonstrable parliamentary majority for a UK-EU withdrawal treaty and an accompanying political declaration about the future trading and security relationships. Sir Graham Brady, chair of her ever more powerful backbenchers, has provided her with a route out of her difficulties by asking for an amendment to the treaty. Or so some think. Jacob Rees-Mogg and the other members of the European Research Group faction have indictated that they will not support Sir Graham’s amendment. Ms May will be fortunate to win any vote that will help her in the negotiations.

The trouble is, the EU has already considered altering or finessing the treaty and rejected it. That is why Ms May signed up to the deal after two years of going around in circles. She is now proposing to go around in circles again, even though nothing, substantially, has changed, because no one has found an answer to the customs union conundrum that presents itself with unique, violent force on the Irish border. Ms May is not going to be arguing with Michel Barnier or Angela Merkel or Leo Varadkar or Emmanuel Macron or Jean-Claude Juncker. Tough as they can be, she has a more formidable opponent, which they merely give voice to: sheer logic. Even a 650-to-nil vote in the Commons cannot trump that.

So she will come back once again, perhaps after presenting another proposal and after another awkward dinner with the European Commission, washed down with some excellent Margaux, near enough empty handed. As she herself has warned, she may even find the Spanish wishing to reopen the Gibraltar question, or that other bits of the unratified treaty have started to unravel. Perhaps most humiliatingly, the upstart European Parliament is certain to veto a new treaty, as an equal partner not just of the EU council and commission, but also of our 800-year-old House of Commons.

There will then be the real crunch vote, towards the end of February. This is the point at which the Commons will have to act, and at which the prime minister will be forced to allow her cabinet colleagues and other ministers a free vote on averting the nightmare of a no-deal Brexit. She is simply not strong enough to survive a mass walkout by Amber Rudd, Philip Hammond, David Gauke, Greg Clark and a score of other ministers. At that moment, absurdly late in the process, push will come to shove, the going round in circles will have to cease and the cliches will run out of steam. It will not be over, though.

The only options then remaining will be an extension of the Article 50 process, because the UK will still have no Brexit policy, almost three years after the referendum. An extension will certainly be granted by the EU – but only provided that it is for a purpose, and is not merely an excuse for the British not to hand in their homework and indulge in weeks more speculation about the Norway and Canada models.

Pausing Brexit is there, in other words, to allow the UK to resolve its internal differences, via due democratic process. As a Final Say referendum on the terms of Brexit is preferable to a general election – which might well resolve nothing – the second referendum will occur for the want of anything else viable. Even so, it is the right thing to do, and the best thing to do, given where we are now.

In reality, pulling back the curtain of parliamentary procedures, the British people, from Europhiles to hard Leavers, deserve their direct say on Brexit as it has turned out, as a concrete proposition, to be set against staying in.

Importantly, too, a “blind” Brexit would be avoided; because the final deal to be put out to the British people should cover the new UK-EU trade and security treaty, which no one has even started to discuss. Remember the mantra “nothing is agreed until everything is agreed”? The “divorce” and new relationship were two sides of a £39bn coin. At the moment we have neither. The House of Commons is, in effect, being asked to approve a future trade deal that does not exist. That really is beyond logic.

The options in a Final Say ballot would need careful and fair consideration; the campaigns would have to be properly regulated by the Electoral Commission, and it would take time to legislate for and organise. But that time would be there, and the country would be more able to be at ease with itself and its place in the world.