What do you mean you had no idea that there was another member of the Johnson clan in politics? And he’s an MP?

Yes, he is, although he is now no longer a minister, having resigned from the government on Friday evening. His departure has already been dubbed JoJexit. This is the latest chapter in the endless saga of the Johnsons, who seem to think the rest of us are mere extras in their family story.

Jo Johnson – brother of erstwhile Brexit leader Boris – said that the Brexit talks have been so poorly conducted that the resulting potential deal represents the worst British policy failure since the conduct of the Battle of Hastings. Or was it Suez? He’s a Remainer and now demands a second referendum to heal British democracy. Incidentally, if he thinks voters being asked to vote again to deliver the “correct” answer this time will heal British democracy and society, then he needs his head examining.

But for all that Brexiteer Tories will try to say this episode is of little significance because of Jo’s relative lack of fame, it matters, potentially rather a lot.

Why? It increases the chances of those wanting to vote down a deal in the Commons. Consider what it does to the government’s calculations on the numbers on the vote when it comes to a deal – if it ever appears. Number 10 already knows the furious DUP is in play and might not vote for the deal. There’s a group of hardline Tories prepared to vote against. It remains to be seen whether that group numbers twenty or as many as forty. Add the sprinkling of hardline, fanatical anti-Brexit Tory backbenchers, and the government then needs an awful lot of Labour support to get a deal through. Unless Corbyn whips in favour of a deal. Imagine it.

Now, with Jo Johnson’s surprise resignation, the situation gets even more dangerous and unpredictable. Who will be the next to walk? How large is the as yet unspecified group of anti-Brexit Tories lurking inside government waiting to quit on the same basis as Johnson? Pass.  Are there also a few pro-Brexit ministers primed to walk too in the coming weeks to vote against May? Sounds likely. The hunt is now on, creating an even more difficult scenario for Tory chief whip Julian Smith and his team to game.

Not everyone has figured this out. One ministerial source unwisely told Sky News: “We haven’t got an offer yet, so this is a meaningless resignation. Quite why he chose to do it now is beyond me.”

Think harder. It’s obvious why Jo Johnson has chosen to do it now. This is clearly part of a coordinated programme by the People’s Vote crowd to undermine the tail end of extremely difficult Brexit talks this month, when May is in France hoping for a little help from President Macron on the fringes of the Armistice commemorations.

More on all this, and how Brexit now hangs by a thread, in my weekly newsletter for Reaction subscribers out tomorrow.

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