Jeremy Corbyn’s Labour Party is now untenable. It is not tenable for 172 MPs to repose no confidence in their leader. It is not tenable for the leader of the Labour Party to accuse his deputy of “baseless conspiracy theories” and his deputy in turn cannot, in all conscience, suggest to the British people that they make Mr Corbyn their prime minister. If Mr Corbyn sees off Owen Smith and is reconfirmed as leader of the Labour Party he will be appointed as its grim reaper. Things have fallen apart. The left cannot hold.

It is not that the case for a new party in British politics has suddenly become good. It is that the case for all the other options is worse. Labour’s deputy