At the end of the worst week of his political life, Gordon Brown is still standing – just. The question is whether he can still govern. That must be answered because, with the challenges it is facing, Britain desperately needs a government.

After a wipe-out at the polls and a walk-out from his cabinet, the prime minister’s authority is in shreds. As Friday’s bungle of a reshuffle demonstrated, Mr Brown plainly does not have the power to choose his own cabinet. Conservative leader David Cameron’s jibe that ministers were reshuffling themselves was a bull’s-eye.