In November of 2002 I was getting a little ahead of myself, and writing about war crimes. The excuse, then and subsequently, was that I was not the only one. The other extenuating circumstance, granted the retrospective justification of five long and horrible years, is simple: every fear was then fulfilled. Worse, foresight required no cleverness on anyone's part.

The list was commonplace. No weapons of mass destruction, thousands dead, resistance, terrorism, inevitable regional unrest, bloody religious strife and the certainty, sooner or later, of civil war: that was the miserable bet. Democracy, peace and stability were not on any of the cards. Instead, for answer, we got astounding complacency, remarkable military incompetence and a series of deceits. What we did not get was a surprise.

As the fifth anniversary of shock, awe and invasion rolls around with no plausible end to the occupation of Iraq in sight, that detail is too easily forgotten. These days the culprits gladly confess their errors (always well-intentioned, of course), but they overlook this part of the tale.

They were warned, warned repeatedly, warned when they were hustling Hans Blix's inspectors from the scene, warned when they mounted the charade of seeking a second UN resolution. Anti-war protests were the visible, public aspect of a global argument in which every serious question went unanswered and every prediction went unheeded. Five years ago, as the bombs began to fall, it was already clear that the conquest of Iraq had been part of the George Bush game-plan from the start. Even the hunt for Osama bin Laden - this piece of cynicism remains breathtaking - was rendered a secondary issue. Bush wanted his war.

By that time, many people on both sides of the dispute were reduced to repeating themselves. Positions were established even before the killing started, even before the excuses for the invasion had become a kind of regressive series of increasingly incredible untruths. Before the shooting, remember, Tony Blair was telling the Commons that regime change in Iraq formed no part of Britain's desires.

In November of 2002, in any case, I wrote the following: "The argument, to hear the White House and Downing Street tell it, runs like this. Saddam is a monster; Saddam is probably a dangerous monster; therefore, somehow, numerous Iraqi dead are the price we' must pay to see him off. It's his fault, not ours, and we're really very sorry. But nothing remotely resembling a crime could possibly be involved."

It was a crime in the making even then, by all the usual standards. Britain and America were not under attack. Having spent years bombing Iraq in a piecemeal way, they had no evidence that an attack against them was imminent. And they lacked the UN's endorsement. Those, crudely, are the rules.

As time went on, however, the two governments began to prefer the monster theory, the humanitarian justification. They began, in fact, to heed self-styled liberal interventionists who had derived an ad hoc policy from a simple observation. Saddam was a beast: no-one disputed it. The western powers, therefore, had a moral obligation to end his tyranny after years of encouraging and tolerating the thug. Intervention might not be strictly legal, but it would be wholly legitimate. Why should a divided and disreputable UN have a veto over justice?

It was, and remains, the only good argument ever mustered for the war. Even today it is still deployed as a last resort, as the moral clincher that excuses an entire catastrophe. Would you rather, they ask, have preferred for Saddam to stay in power?

The liberal interventionists knew what they were about. They understood public opinion. They still do. Who has not demanded that "something must be done" when the latest warlord commences the latest unspeakable act? Who opposes an end to ethnic cleansing, mass murder and genocide? The sole excuse for the Iraq war - and Blair himself grasped for it in the end - was the Hitler parallel, the Pol Pot comparison. Who talks of democracy and then stands aside?

It was not enough, five years ago, to point out that the United States and its coalition were selective indeed in their choice of enemies. The liberal interventionists, the smart ones, would grant you that. Yes, they would concede, there is hypocrisy at work. Yes, it's true, the west has tolerated and fostered some filthy regimes. But does any of that matter when the prize is Saddam's downfall? The end, some alleged, matters far more than the motives of George Bush.

Five years on, with the commanders of America's Iraq "surge" fearing - an exquisite euphemism - a "reverse surge", we can see where high-minded war-mongering took us. International law means precious little to any government, least of all the most powerful government of them all. The UN is relevant only in so far as it assists US presidential candidates with their promises, if any, to remake their country's image.

Elsewhere, a Nobel economics laureate, Joseph Stiglitz, puts the cost of Iraq to the world at $6 trillion (and asks if the money might just have been better spent). In Britain, meanwhile, on-the-books spending on two wars leaps by 94%, to £3.297bn while The Herald's Ian Bruce reminds us of all the other, vastly greater, human costs. The official figure is disclosed - who didn't see this coming? - just after a young royal has been repackaged as Prince Valiant.

The price to the Iraqis that some worried about in 2002 and 2003 is in dispute still. In dispute, that is, if you really require to attach precise numbers to grim adjectives. For the survivors, there is nothing resembling a functioning society. In July, when the American surge abates, the slide towards civil war will continue. Meantime, in addition to the 16,000 US casualties Bush never mentions, there are various figures to account for the nameless and innocent.

As of October last year, the Iraq Body Count project said 74,000 to 81,000 dead. As of July 2006, the Iraqi Health Ministry was estimating 100,000 to 150,000. Others have come up with vastly greater totals, totals you could reduce by half and half again while still applying the word massacre. Opinion Research Business, a British outfit, has concluded that by September of last year 1.2 million Iraqis had perished.

A price worth paying to salve the guilt of westerners determined to challenge tyranny? Or just a reminder that sometimes intervention can make a dire situation worse? Perhaps, equally, the revolting statistics that form our limited understanding of western activities in Iraq and in Afghanistan offer a very simple answer: motives always matter.

After all, the one truth that no-one guessed five years ago was perhaps the most damning of all. Bush, with Blair in tow, had no plan for the aftermath. Reconstruction and a country's recovery were somehow meant just to happen. Liberty's balm would heal all. But neither Britain nor the US ever meant to take responsibility for its application.

The result has been five years of occupation, death and misery, with no end in sight. At this point in a previous, better war we already knew that Hitler was done and Europe saved. Liberal interventionists no longer make the comparison. They no longer have much to say, in fact. Some of them are as silent as the countless graves.