IT WAS NEVER likely that Theresa May would get much out of this week’s European Union summit, just three days after she pulled a vote on the Brexit deal in Parliament and only a day after she won a tight confidence vote in her party. Summits need more preparation and time than this. Yet, although she gamely insisted that the summit’s conclusions were “welcome”, the truth is that they offered less even than she had hoped for. Her chances of securing more changes in a few weeks’ time are not looking good.

The bone of contention, and the reason why so many MPs are so loudly against the deal, is the Irish backstop, a plan to avert a hard border in Ireland in any circumstances. Under the backstop, the United Kingdom as a whole would stay in a customs union with the EU, and Northern Ireland would maintain near-complete regulatory alignment with the club’s single-market rules. EU leaders confirmed this week that the backstop was not intended to be used and that, if it were, it would take effect only temporarily. But they rejected Mrs May’s request to set a one-year time limit for how long it might last, arguing quite reasonably that to do so would negate the backstop’s purpose.

Worse, the summit leaders removed from the draft of their formal conclusions any reference to the backstop not being desired by the EU, as well as any reference to their being ready to offer further assurances to help Mrs May ratify the deal in Parliament. Their mood was one of exasperation with the British prime minister. Donald Tusk, the president of the European Council, declared flatly that there was no scope for any renegotiation of the Brexit deal. And Jean-Claude Juncker annoyed Mrs May by accusing the British of being “nebulous and imprecise” over what they wanted.

Beyond these testy exchanges, EU leaders would like to help Mrs May get the deal through. Two things constrain them. The first is that they are unwilling to make legal changes to the carefully drafted text of the Brexit withdrawal treaty, which includes the backstop. All they will do is agree to some form of clarification, decision or perhaps a joint interpretative text that would qualify but not change the treaty’s legal form. The second is the fear that no matter what new documents they might issue, the deal will still be shot down in Westminster—a view that naturally limits their readiness to be helpful now.

What next? Mrs May talked of needing further work in the weeks ahead, but she also repeated that she would put the Brexit deal to a vote in Parliament before January 21st (government whips now talk of January 14th). It will be hard for the EU to come up with more assurances about the backstop before then. So the likelihood is that MPs will vote the deal down. Mrs May will then have to return to Brussels, perhaps for an emergency summit in late January, to ask for further help. Especially if the defeat is large, she may not get it.

Since Brexit is due to happen on March 29th, this timetable inevitably raises fears on both sides that Britain will end up crashing out with no deal. The European Commission will next week publish further plans for coping with a no-deal Brexit. Neither side wants this. Indeed, since it would happen at a time when the European economies are fragile, it could trigger not just chaos but recession in Britain and in some other EU countries. Wiser voices in Brussels and London are making reassuring noises about some way being found to avoid such a disastrous outcome, perhaps by extending the timetable. But as historians of Europe know well, accidents can and do happen.