Theresa May's Salzburg humiliation confirms that a full blown political crisis is coming

When the prime minister is sweating profusely, tripping over her words and chewing on her own gums as if lost on the way back from the dance tent at Glastonbury at 4am, well, it’s not unfair to come to that conclusion

Theresa May’s problem is that she is fundamentally a decent, functional human being. She is not struck down with the Messiah complex. She does not lie easily or well.

So when she stands on stage at a press conference, her teeth gnashing, her eyes wide and wild, as if everything has gone utterly terribly wrong and she hasn’t got the first clue what she is going to do about it, then you can be absolutely sure it’s because everything has indeed gone utterly terribly wrong, and she hasn’t got the first clue what she is going to do about it.

She had been humiliated, and then she was forced to humiliate herself. She had thought this informal summit of EU leaders in Salzburg would be the final breakthrough on an exit deal from the European Union.

But there has been no breakthrough. There is still a chasm of empty space between her red lines and the European Union’s. The question of the Irish border appears unresolvable.

Either Northern Ireland stays in the single market and the customs union, or the whole of the UK does, or there is no deal. None of these options are satisfactory for the UK.

It is for this reason that pundits and politicians have spent much of 2018 predicting a full blown political crisis in the United Kingdom this autumn. And when the prime minister is sweating profusely, tripping over her words and chewing on her own gums as if lost on the way back from the dance tent at Glastonbury at 4am, well, it’s not unfair to conclude that that is exactly what is coming.

On Monday night, by the way, the BBC broadcast its Panorama programme, in which it had spent two weeks shadowing with the prime minister. One scene now springs to mind, and that was the meeting of her Brexit ”war cabinet”, in which her smooth, ever so slightly oleaginous Brexit Whitehall supremo, Olly Robbins, informed her that “in Brussels the white paper has been a game changer”.

That white paper is the one that set out how a frictionless border could be maintained on the island of Ireland, without Northern Ireland remaining in the customs union. She had gone to Salzburg on this advice, where she found out, in the full glare of the public spotlight, that the game remains exactly the same. As the phrase goes, nothing has changed.

It was unnervingly close to a full-on public meltdown. It was, at moments, Keeganesque. By the end, she may even have told the assembled crowd that Donald Tusk is going to have to go to Middlesbrough and get something.

Indeed, the football analogy is an appropriate one. At the end of the contest, both managers had to give press conferences. Donald Tusk was calm, assured and slightly sad as he said the “Chequers agreement will not work”, and that it risks undermining the single market. It is an unconventional fixture, because a defeat for one is a defeat for both, but after Salzburg, you can’t be in any doubt about which side needs it more.

That Theresa May was reduced to a brittle husk of anger is because this kind of pure frustration emerges only when you know there is no one left to blame. No one else at whom the finger can be pointed, because the defeat is entirely your fault. A customs border in the Irish Sea, whilst humiliating in any circumstances, is simply impossible when your government depends on Northern Irish MPs because you squandered your parliamentary majority.

Especially when it appears, and this is the really shameful part, that David Davis and Boris Johnson have resigned because they were right all along. That the precious Chequers agreement, which nobody ever agreed on, was dead on arrival.

May stated, several times, that “there will be no second referendum” and that “the people have already made their choice”. Politicians can end up with catch phrases like this because they are constantly asked the same question. Like David Cameron, saying over and over again that he would not quit if he lost the referendum. And Theresa May, saying at least 20 times that she would not call a general election.

They are forced to repeat these answers so many times because nobody believes them. Over the coming months, the more you hear Theresa May ruling out a second referendum, and the more she seeks to shift the blame on to Labour, heaping pressure on them to clarify their position, you can be sure it is because the likelihood of a second referendum is growing.

It may yet be the only way out of the mess. And the mess has never been clearer to see, more nakedly demonstrated, than in Theresa May’s eight mad minutes in front of the cameras in Salzburg. It was the lowest moment of her premiership thus far, and that very much includes the time she was being openly mocked by a lord with a bucket on his head.