IT is my fervent hope that one of these days it will be possible to discuss something other than Brexit. I’m not sure, however, that I’ll live to see it. We may face decades yet entangled in things that sound like thriller titles Robert Ludlum rejected: The Brady Amendment, The Malthouse Compromise, The Backstop Reconfiguration.

It took us 40 years to decide we’d rather get out of the EU, though, and it wouldn’t surprise me if we spend 40 more arguing about whether we have, in fact, left or not. When he was Prime Minister, James Callaghan – as his then son-in-law Peter Jay injudiciously revealed – saw himself as Moses, leading his people through the wilderness. Theresa May is even less likely casting in that role, but you’ll remember that Exodus had 40 chapters, and we’re still quite near the beginning, perhaps round about the stage in the story where people threaten to smite the borders with frogs. Lamentations will come later on.

Unfortunately, while Exodus had the most reliable author possible, we’re getting a narrative on which no one – even its authors – agrees. The votes this week, for example, were hailed by politicians and commentators as killing off the withdrawal agreement, giving it another stab, fatally undermining it, showing a way to fix it, making no deal less likely, making no deal almost certain, improving the chances of the EU offering concessions, encouraging the EU not to shift an inch, and anything else you can imagine.

It would have been a good deal more honest to say, we don’t know. Which is, alas, what we ought to say to most of the suggestions for how Brexit might play out. Still, some aspects of the story are possibly a little clearer, and some future developments in the plot more likely than others.

I have no idea, and nor does anyone else, whether the EU will make any significant changes to the withdrawal agreement, which it says cannot be renegotiated. But it is the EU which said at the beginning that nothing is agreed until everything is agreed, and who voiced approval when Parliament insisted on having its say in the deal. Bearing that in mind, the fact is that the shape of a possible deal on an orderly – as opposed to a “no deal” – exit, is very slightly clearer.

Or, at least, there is a clear mandate from the Commons for what they don’t want: they don’t want to remain, they don’t want to extend Article 50 (Yvette Cooper’s idea), they don’t want a second referendum, they don’t want “no deal”, but they may be prepared to vote for Mrs May’s deal if she can secure changes to the Irish backstop.

A lot of sceptics describe this set of priorities as a unicorn, meaning no such thing can exist in reality. That, I think, is to mistake what reality is. Reality includes a lot of things, including unicorns, which people imagined and then wrote down. Treaties and trade agreements – though this is, let’s not forget, not a deal about our future relationship with the EU, merely about how we leave – are not fixed natural features of the landscape, they’re things people invent and bring into being. If it comes to that, even physical features like national borders are artificially created.

Those who imagined that a second vote, or simply remaining, could happen should now concede that the parliamentary arithmetic makes that a more fanciful idea than some amended version of the withdrawal agreement going through. The prospect of some sane Norwegian or Swiss-style Brexit, unfortunately for those of us who hoped for that, also looks much less likely now.

The same is not true of the vote disapproving of no deal in principle, however, and not just because it was advisory, and has no legal force. It’s theoretically possible that – if no adjustments are forthcoming on the backstop – Parliament will try to vote to call the whole thing off, or at least to delay. But given the difficulty of finding any mechanism to avoid no deal so far, it’s hard to see how, especially given that there are enough MPs – including Labour rebels, judging by the majority this week – who think that the political fallout of not leaving will be even worse than any disruption a no-deal Brexit might bring.

Parliament, whatever individual MPs may want or think, is clearly not prepared to imagine a hard border in Ireland. But if they’re insisting there shouldn’t be one, it should make it obvious that the only group arguing for this horrible prospect are the EU.

The strangest aspect of the argument over the border is how seldom anyone points out that it already exists, with restrictions on goods and differences in taxation on either side, and that there was free movement of people across it long before either Ireland or the UK joined the EU. If it becomes a more difficult border in future, it will be for one reason only: the preservation of the EU’s single market. That’s also, by the way, an indication that the single market is not some idealistic free trade area, but a protectionist tariff arrangement for the benefit of EU member states.

The question is which of the two stories told by the Commons votes the EU chooses to listen to. One is that there is, potentially, a Commons majority for the withdrawal agreement – which, I should point out, is a truly terrible deal for all sorts of reasons which have nothing to do with the backstop, and probably worse than either staying in the EU or leaving without any exit deal – but only if they will drop their claims to enforce and police a section of the UK indefinitely. The other message is that there’s a narrow majority against no deal at all.

That second declaration doesn’t strengthen the EU’s position in resisting any changes in what has so far been put down as much as it might like, however. There was a much bigger majority against the Cooper amendment; that is, against any delay in leaving. The story could, judging by its improbable twists and turns so far, go in almost any direction now, not many of them involving a happy ending. But the only one that avoids no deal and ends this sorry chapter is rewriting the current withdrawal agreement.

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