I'm sorry Sam Parker feels that Tony Blair robbed a generation of their faith in politics. But he seems to be confused about the reasons why the disillusionment set in.

More than a million people marched against war in Iraq, and yet our democratically-elected government didn't allow that to change foreign policy. "Naively", he writes, "I thought a million people people marching past his window would be impossible to ignore."

Well, yes, that was a naive expectation. But he was 16 at the time, so a degree of naivety can be expected. But to look back at those events from the perspective of a world-weary 26-year-old and to come to the same conclusion as his teenage self did in 2003? That's rather... interesting.

The question that springs to my mind first of all is, who told young Parker that a demo would change government policy? What precedents existed at the time to give such confidence to the marchers? The protest marches against Vietnam, or pit closures? Or for nuclear disarmament? Even the anti-poll tax demonstrations would have had no effect if opinion polls had given Thatcher a glimmer of hope of overtaking Labour.

By historical standards, the march through London on 15 February 2003 was certainly large. But did the marchers seriously expect to change Britain's foreign policy? Did we, even then, want a prime minister who would abandon his convictions, however much they disagreed with them, at the first whiff of public protest?

This is a very modern political paradox: opinion polls and received wisdom tell us the public want politicians of conviction. And also politicians who will listen to the people. But also politicians who won't decide every policy by focus group or opinion poll.

You see the problem?

But a million marchers? Surely unprecedented? Perhaps Mr Parker believes a sliding scale should be adopted as a constitutional mechanism for deciding policy? More than 750,000 out on the streets, then it's a done deal - the marchers' views are immediately implemented by ministers. Between 500,000 and 750,000 would force the government to launch a public consultation on whatever issue so infuriates the protesters. Fewer than 500,000? Well, that's their fault for not organising well enough, obviously...

Parker's article reheats some of the tired old arguments about poodles and Dubya and Blair: The US president eventually made "us" despise our prime minister as a result of their association. The writer doesn't quite identify who he meant by "us" - given Blair's record-breaking third election victory two years later, I guess he meant the anti-war protesters rather than the population as a whole.

"When the president said he believed Iraq had weapons of mass destruction, Blair said he believed it too." And here we have the familiar re-writing of history through the prism of the subsequent non-discovery, post-invasion, of Iraq's WMDs: no-one except the US (and therefore, subsequently, Blair) believed Saddam would ever be so beastly as to own WMD. Except that at the time, the vast majority of people and nations - even most of those who opposed war - accepted they existed. Those whose families had actually been wiped out in their thousands by them had particular reason to believe they were real and not a figment of Bush's imagination. It is only now, ten years after the failure to discover the presence of what most western intelligence services concluded existed, that the arguments of 2003 have been subtly revised. I lost count of the number ofd times I took part in TV and radio discussions with opponents of war, and I can't recall one who claimed that the WMD didn't actually exist. Far more often came the rather unpleasant and absurd argument that sure, Iraq may have WMD, but so has Israel! What are you going to do about that, eh?

So Blair came to the conclusion that Iraq owned WMD not because Bush told him (to be fair, Parker's article is the only one I've ever read that posited such a ridiculous scenario) but because the British - and many other nations' - security service told him so. In the run-up to war the argument wasn't between those who wanted to disarm Iraq and those who said he had nothing to disarm, but between those who wanted to disarm Saddam and those who didn't.

And since Parker cites the "peaceful Swede", Hans Blix, who "swept into the darkening saga like a comforting beam from a lighthouse", it's worth at this point quoting from his report into Saddam's regime, delivered to the UN on 27 January 2003:

"Iraq appears not to have come to an acceptance - even now - of the disarmament which was demanded of it and which it needs to carry out to win the confidence of the world and to live in peace." On the subject of chemical weapons, Blix reported: "The discovery of a number of 122 mm chemical rocket warheads in a bunker at a storage depot 170 km south-west of Baghdad was much publicised. This was a new bunker and therefore the rockets must have been moved there in the past few years, at a time when Iraq should not have had such munitions."

On biological weapons: "I have mentioned the issue of anthrax to the Council on previous occasions and I come back to it as an important one. Iraq has declared that it produced about 8,500 litres of this biological warfare agent, which it states it unilaterally destroyed in the summer of 1991. Iraq has produced little or no evidence for this production and no convincing evidence for its destruction. There are strong indications that Iraq produced more anthrax than it declared and that at least some of this was retained after the declared destruction date."

And on the issue of missiles: "In particular, Iraq reconstituted a number of casting chambers, which had previously been destroyed under UNSCOM supervision. They had been used in the production of solid fuel missiles. Whatever missiles these chambers are intended for, they could produce motors for missiles capable of ranges significantly greater than 150 km... Iraq also declared the recent import of chemicals used in propellants, test instrumentation and guidance and control systems. These items may well be for proscribed purposes. That is yet to be determined. What is clear is that they were illegally brought into Iraq, that is, Iraq or some company in Iraq circumvented the restrictions imposed by various resolutions."

In recent weeks, I have been contacted by constituents who have asked me to represent their anti-equal marriage views in parliament. I have had to remind them that I am a representative, not a delegate; democracy is as much about being accountable to the electorate for decisions already made as it is about sticking a finger in the air to decide which way the wind is blowing and then to vote accordingly. Had everyone who feels strongly against same sex marriage taken to the streets of the capital last weekend, it's quite possible they could have numbered more than a million. But supporting the Second Reading of the Marriage (Same Sex Couples) Bill would still have been the right thing to do.

That's not a reason to lose faith in politics. And at the risk of causing offence to Mr Parker, is he sure that he is so representative of his generation that he can authoritatively state that his loss of faith in politics was also the experience of everyone else of his generation? Reduction in turnout at elections continues on its historically inevitable downward trajectory, but is the increase in disillusionment among his own age group that much greater than in every other?

Is not getting your own way really reason enough to disillusion anyone about democracy? For my generation, defeat on issues about which we felt strongly was painful, but we never assumed we had some God-given right to get our own way just because we really, really cared. There is surely a better reaction to defeat than shouting "It's not fair!" then slamming the door and taking your ball home.

Parker is representative, however, of one group of people: of an anti-war movement which thrives on misrepresenting Blair and those who followed him into the lobbies as America's "poodles". The truth is that we did what we thought was necessary to deal with a regime that had already caused millions of deaths in the region and, all evidence suggested, would cause more if left to its own devices. Do not assume that those who took to the streets in February 2003 were any more sincere in their views than those of us who, with heavy hearts and grim determination, walked into the "Aye" lobby a month later.

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