I said on Good Morning Britain (when I could get a word in edgeways with Labour MP Rupa Huq) that I couldn't recall a worse week for a British Prime Minister in living memory. Theresa May leaves Brussels today humiliated, and not for the first time. I have no idea why she thought it would be any other way. At least this time, I suppose Donald Tusk didn't humiliate her on Instagram with a bowl of cherries. No, this time it was Jean Claude Juncker briefing out that he wore a green tie to express solidarity with the Irish.

To go cap in hand into a negotiation is rarely going to end well. Pleading never works either. Not only did the Prime Minister not get any commitment to "clarify" the EU attiude to the Northern Ireland backstop, there were few warm words to emerge either. And even worse than that, someone (no doubt close to the Beast of Berlaymont, Martin Selmayr) leaked the track changes on the final summit communique, just to rub salt into the British wounds.

Embed from Getty Images

The original draft said:

The union stands ready to examine whether any further assurance can be provided.

It was replaced by a call to...

...work on preparedness at all levels for the consequences of the UK's withdrawal to be intensified, taking into account all possible outcomes.

It doesn't get much more hostile than that. And there's more...

One thing is clear. If they really wanted to help Theresa May out of a hole, it would have been relatively easy to do. Instead, they see a fellow political leader holed below the political water line. They chose not to bail her out, but punch a few new holes for good measure. Fine. Perhaps after two years of this sort of treatment, Theresa May will now finally realise that they've been playing her all along. She's capitulated on virtually everything, and now she's suffering the consequences.

There is no way out of this for her. It is impossible for her to get the Withdrawal Agreement through the House of Commons. Indeed, it seems pointless trying. This means we are entering a real constitutional crisis. The calls of the 'Loser's Vote' lobby will feel renewed wind in their sails, not least because they know there is a group of Cabinet ministers who are on their side. And it's these ministers who Theresa May is increasingly listening to. Therein lies her problem. All she has done is listen to people whose real agenda is to make Brexit work, but to thwart it. What the ERG don't realise is that they're playing into the hands of these ministers.

As clear as night follows day, the agenda in this section of the Cabinet is to argue for a referendum on the Withdrawal Agreement, which would mean extending Article 50. i.e not leaving the EU on 29 March 2019. And of course they will ensure that Remain is on the ballot paper. There are even those who argue that the question on the ballot paper should be beween the Withdrawal Agreement and Remaining, with 'no deal' not even an option. Can you imagine the aggro that would cause?

It is now that maybe the more hardline of the ERGers might wonder if Michael Gove wasn't right all along. Accept the deal, imperfections and all, in order to ensure we actually do formally leave on 29 March. Because once we've left, there's no turning back, and everything else can be sorted after that. That ought now to be the main debate among Brexiteers. Should they hold their noses and vote for the deal or accept that if they don't, we won't be leaving on 29 March.

That is the debate which should rage over the Christmas turkey...