One of the great myths of the parliamentary battles over Brexit is that there is going to be one big-bang vote that solves the problem. If only Theresa May and her acolyte ministers can cajole a few Labour or Lib Dem or SNP votes to counter the Tory MPs implacably opposed to Europe, all will be well.
But it won't be. The 30 months of contemptuous treatment of the opposition parties by the prime minister on the question of Brexit – and her scorn for any suggestions from the likes of Jeremy Corbyn, Nicola Sturgeon or Vince Cable – have ground away any possible support for her Brexit deal.
John McDonnell made that clear on Radio 4's Today this morning. McDonnell and Corbyn, life-long supporters of a united Ireland, are now in an alliance against nature with the ultra unionist DUP.
The contortions of McDonnell's view that Labour can negotiate a different deal, one that rejects core EU values on freedom of movement and other EU rules to allow a unique Labour cake-and-eat-it version of Brexit, are not important. The fact he and Corbyn are sending billets doux to the DUP is.
It shows that a new front of implacable anti-May opposition is firming up.
The opposition parties look at the 117 Tory MPs who voted against their party leader and realise her time is up. They will not do her any favours. In the 19th century, Randolph Churchill said the duty of the opposition is to oppose. That is precisely what 300 opposition MPs plus the DUP are now doing.
It now looks close to impossible for the "meaningful vote" on the Brexit deal to go the government's way. The backstop won't be changed as Dublin has the united support of 27 sovereign European states that they will do nothing that risks a return to tension and violence in Ireland.
More words can be added to the "Political Declaration" on our future relationship. But even if that succeeded in peeling off some Labour MPs it would only need a handful of the 117 Tory MPs determined to be rid off their leader for the government to lose the vote.
In addition, and never mentioned by the BBC nor most coverage of the parliamentary politics of Brexit, is a raft of legislation that is needed to go through the Commons to give effect to the deal, plus all the necessary changes in law for the UK to be fully and legally outside EU rules.
It is now clear that there is no majority in the Commons for this legislation. So the Conservatives as a party have to decide if they really want to blunder on, making the kind of spectacle of themselves we have seen this week.
Or do they save their party from internal collapse? The best way to do that is to hold a People's Vote. Perhaps even Theresa May will come round to seeing that handing this mess back to the people is now her only escape route from going down in history as the woman who destroyed the Tory party.