It is sometimes said that public figures who live to a great age, no matter how reviled in their day, eventually become respected, even loved. Michael Foot is a testament to the acuity of that observation. Not many British politicians have been more reviled than the donkey-jacket wearing, unpatriotic, election-losing Foot. And yet there was not the faintest edge of ancient grudge in any of the generous tributes paid to the former Labour Party leader yesterday from across the political spectrum.

So how can this remarkable transition from national rejection to national embrace be explained? The answer lies, partly, in the fact that Foot belonged to quite a different political era, one that was so comprehensively ended by the Thatcher revolution and so deeply buried by New Labour. The sense of threat which Foot's brand of socialism once instilled faded long ago. His views became something of a historical curiosity, rather than something to keep people awake at night.

The change in mood towards Foot is partly, too, because the passing of time confers a broader perspective. People can look back now and recognise that, whatever his failings, Foot lived the fullest possible life, indeed, one of the great public lives of the 20th century. He straddled radical politics and radical journalism for 60 years; a man of letters who believed that his job was not to interpret the world, but to change it. His wartime pamphleteering was in the great liberal tradition; populist and excoriating. And his writing talents lifted Tribune, the Daily Herald, and Beaverbrook's Evening Standard.

Foot also had a long, mostly rebellious, career in Parliament. This disciple of Aneurin Bevan had the whip withdrawn because he opposed increases in defence spending and later refused to serve in Harold Wilson's first two administrations for similar reasons of principle.

Foot also founded the Campaign for Nuclear Disarmament and supported a "no" vote in the 1975 referendum on Britain's membership of the European Economic Community. Although he was on the losing side of most battles, he was described by Enoch Powell (no shabby orator himself) as "the outstanding parliamentarian of our time". His oratory is still recalled with awe today by those who were around to hear it.

But by the time Foot became party leader in 1980 he was simply the wrong man for the times. He had stood as a unity candidate but was unable to provide the strong leadership that was needed to keep the party together. The Gang of Four broke away to form the Social Democratic Party. The militant left were rampant. And it all ended in the worst defeat for Labour in half a century after the party put forward an unreconstructed left-wing manifesto. There followed Neil Kinnock and the party reforms which would eventually sweep away all the crumbling pillars of Foot's socialist worldview. It is a truism that all political careers end in failure, but Foot's failure, as a party leader at least, was monumental.

Yet the trauma of his time as leader never twisted him personally. He was always a palpably decent human being, shaped by his enthusiasms outside the narrow confines of party politics. Foot is now seen as an admirably authentic political figure and a great 20th century radical. It might not be the legacy he would have chosen when he set out on his public career all those decades ago. It is, nonetheless, the one he deserves.