If one image conjures up the disaster that was the Tories' 1997 general election defeat it was Michael Portillo losing his seat.
That night was not only an historic shock to the Conservatives, it pitched Mr Portillo into a period of radical self-examination.
And it is probably fair to say he has never been the same since.
In a personal journey that fascinated Westminster watchers and dismayed many of his previous allies, he transformed himself from the tough-talking right winger into the most powerful advocate of liberal Conservatism.
After winning the 1999 by-election in Kensington and Chelsea he was instantly earmarked as the next leader-in-waiting.
It was a second personal blow when he failed to win through to the final round of the following leadership election which saw the party comprehensively rejecting his agenda.
Even then it was said his heart had never really been in the fight. And he has hinted on many occasions since that he no longer found politics as gripping as he once did.
His friends have long believed he was deeply ambivalent about his future in the Conservative party
His decision to stand down at the next election will undoubtedly have been further influenced by the recognition that, while his agenda may now be incorporated to some extent in the new Tory platform, the party has not followed his route.
The decision will, therefore, come as no great surprise to those who know him best.
They have long believed he was deeply ambivalent about his future in the Conservative party.
He has also spent the past couple of years forging a successful alternative career in the media.
That is almost certainly the direction in which he will now attempt to channel his energies and it would be no surprise to find he already has something mapped out.
Relief and disappointment
His decision is still a blow to the Tory party and Mr Howard in particular.
There will be plenty in the rival factions on the Tory benches who will, frankly, be relieved he is going. And he had his fair share of political enemies.
He has the intelligence, ability and charisma to have made a leader, even a prime minister.
He was always a formidable opponent and clearly has the intelligence, ability and charisma to have made a leader, even a prime minister.
They will be delighted the so-called "Portallistas" have now lost their figurehead - with no one anywhere near as potent ready to take his place.
But if there is one thing the top jobs in politics require it is absolute commitment. There is little room for doubters or the half-hearted.
It will be a disappointment to Mr Howard because having Mr Portillo on his team would have been a massive boost and the clearest possible sign that the party was genuinely uniting.
However, Mr Portillo has insisted his decision is nothing to do with Mr Howard's leadership and most will be happy to accept that.
So what this announcement amounts to is the end of another once golden political career.
In particular it is the end of the political career of one of the Tory party's most effective, charismatic and thoughtful operators.