But the anti-war activism which girdled the globe didn't prevail. The invasion went ahead. Three years later, everything the demonstrations warned against has happened.

Nothing that pro-war campaigners promised has come about.

Bush and Blair have had to grit their teeth and acknowledge there were no weapons of mass destruction. What they haven't admitted is, they lied.

Memoirs and memos and minutes have exploded the notion that they genuinely believed in the case that they made. They are as contemptuous of honest truth as they are of human life.

The war has mired millions of Iraqis into misery as deep as they'd endured under dictatorship. Tens of thousands have been detained without trial.

Thousands, at least, have been tortured. A hundred journalists have been killed.

The sinews of civilised living have been shredded. Social collapse, rising disease, random murder and unspeakable cruelty are the order of the day.

Every survey of Iraqi opinion, including those conducted by the occupation forces, shows that a majority of the people want the occupiers out.

Blair composes his face into a rictus grin and talks of "a turning point". But every turning he has taken has led on to new horror.

Bush now concedes that 30,000 Iraqi civilians have perished in the cataclysm he created. But last month, Counterpunchmagazine concluded from data gathered by US academics that the "best estimate for deaths inflicted to date as a result of the invasion and occupation stands at 183,000".

In the second half of last year, there were more than 400 US air strikes inside Iraq. In the last two years, the 3rd Marine Aircraft Wing alone has dropped more than half a million tons of explosives , , compared to two million tons in the entire course of Vietnam. Iraqi towns have been pummelled by pitiless bombing.

Phosphorous has rained on Fallujah, stripping women, men and children to the bone, seared flesh falling away.

All across the Muslim world, the war has embedded the ideology of terrorism which its proponents had been adamant it would extirpate.

They say now . . . it's the last refuge of the pro-war scoundrels . . . that, despite all, Iraq is a better place than it was when ruled by Hussein.

Even if this were true, and it's by no means clear, it wasn't the reason for going to war and it justifies nothing in retrospect. What kind of moral measurement is this anyway? Are these the only alternatives Bush and Blair can conceive of for the people of Iraq? As the US activist, Dylan biographer Mike Marqusee, mordantly observed last week, "For the dead, injured, impoverished and abused, this kind of calculus never adds up."

Many have been dispirited by the failure of 15 February.

We were in the majority, we have been vindicated since, but the war happened anyway and the occupation continues. What's the point of protest? I suspect this is the reason demonstrations have become smaller. It's not opposition to the war but faith in democracy which has faded.

But the most important achievement of 15 February lay not in how it affected or failed to affect the trajectory towards conflict, but in the fact that it put on display an unsuspected superpower that has not yet flexed its muscles fully, the international mass movement for peace and against oppression which has grown in the shadow of capitalist globalisation, and upon which our best hopes for a better future now depend.

In London in December, along with Kay Duddy, Alana Burke and Regina McKinney from the Bloody Sunday families, I attended a huge meeting at which the diverse voices of rising Iraqi democratic resistance rang out. Hanna Ibrahim of the Iraqi women's group Woman's Will, held up a picture of Condoleezza Rice:

"I don't belong to the same gender as this woman. She kills our children. She talks of women's rights while her teeth bleed with the blood of my people. Her and her government brought terrorism to my country. I hear that if the US loses 5,000 troops they will withdraw from Iraq. So we need to kill 3,000 of them to make them leave? What kind of civilisation is this, that needs killing for there to be peace?"