There is a touch of life-or-death for the UK about June’s European council, because talks on our future relationship with the EU would be halted, in the absence of sufficient negotiating progress to maintain an open border between Northern Ireland and the Republic.
That is the significance of the Telegraph’s scoop that Theresa May’s war cabinet has agreed the offer of a new “backstop” proposal to the EU - to potentially replace the EU’s plan, which May rejects, that Northern Ireland should in effect remain in the customs union and single market after Brexit.
May’s counter-offer to the 27 EU government heads will be that after transition, on 31 December 2020, there would be a temporary period of the whole UK retaining most of the important obligations of staying in the customs union for a limited period.
So even though by then the UK could have negotiated new free trade deals with Australia or even the US, we would not be able to waive tariffs - we would have to still levy the EU’s tariffs on their goods when they enter the country.
And that is one reason why this backstop idea was so toxic to Brexiter cabinet members, especially Gove and Johnson, and will be toxic to Brexiter MPs, like Rees-Mogg.
Now for the avoidance of doubt, although this is a significant victory for May over the arch Brexiters in her government, it solves very little of substance in respect of the passionate arguments over what Brexit should be in practice.
Remember this backstop is supposed to be a bridge from 2020 to whatever our permanent new customs arrangement with the EU will be. It is not a choice between NCP (being the EU’s tariff collector forever) or Max Fac (tech solutions to prevent border checks). That decision is yet to be made - though all my money is on Max Fac being the eventual choice.
But perhaps more importantly, I simply cannot see this backstop being deemed adequate by the EU27 unless it is accompanied by a pledge from the UK to maintain full alignment with the EU’s product and food standards for just as long as the backstop is needed (I should point out here that the PM retains a hope that all new customs systems could be in place by the end of 2020, and the backstop would then be academic - but few UK or EU officials agree with her).
So you will immediately grasp why Brexiters see this backstop as a Trojan Horse to keep us in the single market, even perhaps forever - if the Max Fac tech never does what it is supposed to do.
In other words, May still has to decide whether to face down her Brexiter colleagues, by opting for a soft Brexit, or spurn the rest of the EU, by rejecting their notion of how to keep the Irish border open.
All her war cabinet has achieved with its agreement on the Irish backstop is a gentle tap on the infamous can - which she’s nudged a little bit further down the road. We continue to wait for the Godot of May’s big Brexit choice.