Saturday 15 February 2003 saw the largest public protest in British history.
About a million people marched in London in opposition to an impending war against Iraq. That historic day in the UK's capital has been made the setting for Booker prize-winning author Ian McEwan's new novel, Saturday.
Speaking about the book, the author says he was opposed to the war, although less resolutely than many friends and colleagues.
The US-led coalition toppled Saddam Hussein's regime in three weeks, but the justification for war - the alleged possession of weapons of mass destruction - proved baseless.
In Iraq the battle continues, now against insurgents. At the same time, Iraqis themselves no longer live under Saddam's murderous regime and last Sunday saw the country's first free elections in 50 years.
So two years on, how do those who protested now feel about the war? And - below - if you didn't go on the march, tell us about your thoughts on the last two years.
32-year-old teacher Simon Green
I was there to show my disgust and distaste at the war and the whole premise behind it, i.e. the weapons of mass destruction. I didn't approve of Saddam's reign, but I certainly didn't approve of all the excuses given for the war. It has gone very, very badly. They call it anything but a war in the media, but there is continual loss of life. We don't know how we can withdraw while things are the way they are. It's a Vietnam situation - there is no real way out. I think it has been handled in an extremely messy way. Yes, you have democratic elections and democracy, but at the same time people are being blown up virtually daily.
Anna Hoyles, 26, homeless shelter worker, south-east London
I think it's great they got rid of Saddam and there have been elections, but I really don't think the future is that bright for Iraq. I cannot see America leaving in the foreseeable future. The reason they were doing it was to get the oil for US companies - they are not going to give that up. They are not going to have spent all that money on a war and just say, 'Here's democracy. Goodbye.' The march made a difference. We heard afterwards how close they were to not going to war, how worried Blair was about public opposition. Maybe he will think again next time.
John Brook, of Weybridge, Surrey, who marched with his girlfriend Michelle Haeems
I have been on a few of the smaller marches as well, and I would do it again all day long. We both feel very, very strongly about it. I lost a little bit of heart, because no-one listens. But there is value in trying to get heard that you are against the war. Two years on, there is more violence in Iraq and more of our boys being killed. For what? A little bit of oil. I think it's disgraceful in light of what happened with the tsunami. The money that's going to those countries is just a fraction of the billions we are chucking into a war.
Donald Chambers, 33, town planner, London
I went on the march with a group from my church. I still argue that the war was wrong, but now that it's happened, that Saddam has gone and that the elections have been held, it's the West's responsibility to make sure that it works out. It will be a great day if Iraq becomes a peaceful country and able to control its own destiny free from violence and tyranny.
Historian Charles Loft, 40
Irrespective of whether the war has had good outcomes or bad, I have no doubt that it was illegal. Blair's defence, I think, is that it was at least morally right. Maybe it will turn out to be better for those people who haven't been disabled or killed in Iraq. But if you are going to say the end justifies breaking international law, where do you stop?
Iraqi student Wasan Osama, 18, Leeds
My whole family didn't vote because we weren't happy with the elections. The Americans and British were trying to show the world that elections are taking place and that Iraq is democratic - it isn't. The security is just not there. The news showed a lot of people that were going to vote, but a lot of people did not feel happy going out because of the threat to their lives. Whatever results come out are not actually going to be representative of Iraq's whole population. When we talk to people in Iraq, they say, 'We cannot even provide the fundamentals of living, never mind going out to think about democracy at the moment.'
Mithran Samuel, 28, of Morden, south London
It was amazing to get so many people out on to the streets on the same day, across the world. The anti-war movement can take great credit for the critical attitude to the war and occupation that the media and politicians have since taken up. Where it led they followed. I hope it has also ensured that Britain at least will not join America in attacking Iran. The elections are a great step for Iraq but they cannot justify the war. It was illegal, based on false premises and has rather predictably led to thousands of civilian deaths and fostered terrorism in Iraq and elsewhere.
If you weren't on the march, what are your views of it now, and of the events of the past two years?
I thought the recent elections were an outstanding success when one considers the undemocratic Iraq under Saddam Hussein. People will always say, 'What about the WMDs?' but now who cares? Sometimes the end does justify the means.
Dan Cuddeford, Loughborough
All of the above have their beliefs but how many of them would be able to say those beliefs if they were living in Iraq pre-war? You take your liberty too much for granted.
Chris Page, London, UK
As a political consultant in Washington during the war, and now in London, I was against this war. The removal of Saddam was no bad thing, but the bloodshed, lack of hope, and motives of the 'coalition of the willing' all act as evidence that this war should not have taken place. No-one has gained from this other than American corporations, and the Iraqi people, American and British citizens, and allied forces have all suffered. However, I have to disagree with Wasan Osama's comments on the recent election. Whilst she suggests that the elections did not represent the population of Iraq, it must be noted that the turnout was much higher than anyone could have imagined. The turnout in and around Baghdad was more than the UK or US elections. Whatever people thought of the war, it has now happened, and there is no point continuing to attach blame. It is time to do what is best for Iraq. Now this mess has started, it is up to the nations responsible to link with the international community to clean it up, however long it takes. So 'yes' to elections, and 'no' to our troops pulling out and leaving a disaster zone in which Iraqis have no future.
Oli Winton, London, UK
I wonder how many of those who marched in opposition to the war were not moved as I was by those lines of smiling, cheerful Iraqi women in their traditional Islamic dress waiting to vote for a genuine choice of candidates for the first time in their lives. We in safe western democracies take so much for granted.
Tony Church, Lochranza, Scotland
Two questions for the marchers: Did they want Saddam out of power or were they comfortable with him remaining in power, knowing that he was responsible for 400,000 Iraqi deaths? If they wanted him gone, how were they planning on achieving his removal?
Two years later, there is still so much rhetoric. I was anti-war, and still am, but I don't keep repeating soundbites because that gets us nowhere. People throw around statements about oil and legality without knowing any facts about these matters, and that just weakens the anti-war movement by making us look like a load of whiny Michael Moores. If you're truly anti-war then learn the facts more, and don't moan for moaning's sake. Maybe then we can be viewed as a legitimate force for change.
It's remarkable how many people on both sides of the argument suddenly become experts when asked for their opinions on the war in Iraq. The only real experts, are the Iraqis who have had the misfortune to live through this whole horrific ordeal.
Rob Holman, Chislehurst, Kent, England
Many of those who marched vaguely assert that they were opposed to Saddam's regime. But the question is, how many of them marched or protested against him when he was in power? They should ask themselves why they didn't put half the effort into attempting to prevent the actions of a murderous tyrant as they did in attempting to stop those of democratically elected governments.
David Batchelor, Norwich
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