The political landscape is littered with the remains of men who might have been, even should have been, prime minister but who, for any number of reasons - ill luck, ill health, miscalculation, the loss of a parliamentary seat at a crucial moment - never made it.
Michael Heseltine, who yesterday announced his intention to give up his Commons seat at the next election, is one of the most conspicuous members of this fraternity. He never made prime minister; he never made party leader. The reference books will record that he reached at peak the status of deputy prime minister in a government that was decaying and a party that would take many years to resuscitate.
Yet despite this defeat, Heseltine will be better and more vividly remembered than some who got where he couldn't: John Major, for instance, who beat him to the job he most coveted but did that job with so much less swagger and style and sense of occasion; and so much less vision.
Some politicians are stronger on style than content; others are the other way round. Michael Heseltine always had bagfuls of both. His annual conference speech was one of the guaranteed treats of the political season.
Many who came to scoff ended up mesmerised. It was always so good to watch: that recalcitrant lock of hair, gradually escaping from his coiffure, swishing impertinently into his eyes, then swept back into place with a fine imperial gesture.
Later, as he grew older, the lock of hair was replaced by another teasingly eye-catching device: the pair of half-glasses, slipping steadily down his nose as he grew more and more excited, until they seemed certain to slip to the floor - when at the very last moment he would haul them back into obedience.
But it wasn't just the theatre: there was juice in the content too. Learned - but entertaining - excursions into Victorian history or the wars of old Europe, for instance, put there not just for their colour and spice but because they chimed in with essential Heseltine themes, of which the most prominent always were industry, the state of the inner cities, and Europe.
Even that was not the whole of the story. From the mid-70s on, every Heseltine speech had the dangerous tang of a leadership bid about it. The programme would say he was there to reply to the party's debate on industry, or the environment, or whatever department or shadow department was then in his charge.
Once he got going, the whole agenda of politics, at home and abroad, was there for his taking. These were not the compartmentalised thoughts of a mere head of department, but the eager commitments, the foaming enthusiasms even, of a man who meant to be boss.
Nor were these the only dramas. There was Heseltine in a flak jacket, a suitably military figure to have charge of defence. (He had once been an officer in the Welsh Guards, though only on national service.)
There was Heseltine, the friend of the great city in trouble: dispatched to Liverpool after the riots, he produced a passionate and incisive report, demonstrating with a logic which embarrassed some of his colleagues how the city had suffered as great Liverpool-based institutions like Martin's Bank and Tate and Lyle transferred their headquarters (and with them, their way of thinking) to London.
Then there was Westland: that rare occasion, the resignation of a cabinet minister on a matter of principle. It happened in the course of a cabinet meeting: he gathered his papers and swept out of the room. The principle on which he resigned - the conduct of government - was certainly crucial: but so, too, was his personal commitment to Europe; his sense of himself; his ambition.
He was out of the party hierarchy for more than four years, at the end of which he emerged, even more dramatically, as Margaret Thatcher's assassin. Not without skilled accomplices: Geoffrey Howe, whose decision to take no more of her punishment opened the final act; Thatcher herself, for her stubbornness over Europe and over the poll tax. It was Heseltine, though, who by pledging himself to stand against her precipitated the contest which finished her.
After that, he was, for a swathe of his party, "that traitor": the outcast, the man who had slain the queen. He bided his time, serving John Major faithfully (though without disguising his hope that he might yet land the top job himself) and helped shore him up when vicious critics were out for his blood. And for all the venom against him, he came tantalisingly close to winning the leadership.
When Major resigned after Labour's victory, Heseltine was the obvious choice - far more formidable a figure than Major, and, though still a staunch European, more flexible on Europe than Kenneth Clarke. And a way of postponing the really decisive contest until Michael Portillo and Chris Patten, both general election casualties, were back in the House.
What did for him then was ill health. The television pictures which showed him being borne home, haggard and ashen, made it clear that the game might be up. And now he is going, leaving a local party in Oxfordshire which has shown signs of restlessness with him as he went on banging the Euro drum in a party increasingly hostile to the whole European involvement. He announced his decision not to them, not to William Hague, but on one of the battlegrounds he had most enjoyed: the studios of the BBC Today programme.
Wherever he goes after this (the Lords is a clear possibility)
he will have the time and the freedom - given good luck with his health - to bring his crusading passion to a cause which clearly has desperate need of it.