Purnell breaks from the pack to plunge the knife

To answer my own initial question: Purnell has broken from the pack. He has done what David Miliband, conceivably Andy Burnham, and maybe John Hutton (of whom more in a moment), might have done and must have been thinking of doing.

Purnell has plunged a knife that has been waiting for such an exercise for some considerable time.

David Miliband was so badly bruised by events last autumn that I think he has effectively given up any ambition he had to become leader (and I’m not sure he had much in the first place).

Burnham is still too untried to have made much difference – hence the Burnham-Miliband cries of support for Brown in the aftermath of Purnell’s resignation.

So James Purnell becomes the front runner to position himself at least as the leader of the Blairite faction and maybe more.

Alistair Darling has seen off a serious bid by Brown to defenestrate him. It would have been very bad for the appearance of the government’s management of the economy. He has a better record as chancellor than brown himself thus far.

(Read Martin Kettle Guardian online: “Darling should stay but will be sacrificed for his honesty.” It spells out why in the end, despite its headline, Brown’s hands were tied).

The ambitious Ed Balls will now almost certainly never become chancellor of the exchequer. And that will in large part be due to his own involvement in “dark arts” mentioned in my earlier blog.

So that leaves the resignation of John Hutton, a nice man who reached the summit of his ambition in becoming defence secretary. He’s gone without much explanation and so far without negative comment on Brown.

But his mere removal adds to the sense of Brown’s powerlessness: a cabinet reshuffling itself.