Nick Clegg's wildly oscillating political career has taken its deepest dive downward.
This weekend a year ago he was fleetingly the most powerful politician in the land, the leader of a third party in a position to sway tumultuous events.
Now Clegg fights for his party's survival as a distinct and potent national force. Liberal Democrats are suddenly much weaker in local government.
In the aftermath of the election Clegg was hailed for negotiating a brilliantly ruthless, cunningly executed deal with the Conservatives.
In retrospect he was exhausted, and in the grip of fast-moving events. The Conservatives got everything — crucially, support for their plans to wipe out the deficit in a single Parliament and for a programme of public-service reform that implied a revolutionary recasting of the relationship between state and citizen.
The subsequent simplistic accusations of betrayal that were applied to Clegg were wide of the mark. He is a committed public figure who at times has fought assiduously behind the scenes for fairer policies.
In the immediate aftermath of this weekend's trauma, Clegg will be committed to a series of genuinely radical measures.
Unlike Blair/Brown, he dares to utter the word “redistribution” and will exclude the low-paid from income tax. His objectives for improving social mobility are almost revolutionary in their sweep.
He is a radical constitutional reformer and turns his sights on the Lords. He is incomparably more progressive about crime, prison reform and banks than Labour was in Government.
This is one of the big tests in the coming year. Can Clegg prevail in policy areas that trouble Cameron's party? If he can, or indeed if he fails, his party might regain distinctiveness and perhaps discover common ground with Labour.