The Iraqi Government tries to give the impression that normality is returning. Iraqi journalists are told not to mention the continuing violence. When a bomb exploded in Karada district near my hotel, killing 70 people, the police beat and drove away a television cameraman trying to take pictures. Civilian casualties have fallen from 65 Iraqis killed daily from November 2006 to August 2007 to 26 daily in February. But the fall in the death rate is partly because ethnic cleansing has already done its grim work and in much of Baghdad there are no mixed areas left.

More than most wars, the war in Iraq remains little understood outside the country. Iraqis themselves often do not understand it because they have an intimate knowledge of their own community, be it Shi'ite, Sunni or Kurdish, but little of other Iraqi communities. It should have been evident from the moment Bush decided to overthrow Saddam that it was going to be a very different war from the one fought by his father in 1991. The war of 2003 was bound to have radical consequences. If Saddam was overthrown and elections held, then the domination of the 20 per cent Sunni minority would be replaced by the rule of the majority Shi'ite community allied to the Kurds. In an election, Shi'ite religious parties linked to Iran would win, as indeed they did in two elections in 2005. Many of the US troubles in Iraq have stemmed from its attempt to stop Iran and anti-American Shi'ite leaders such as Muqtada al-Sadr filling the power vacuum left by the fall of Saddam.

The US and its allies never really understood the war. Their armies had an easy passage to Baghdad because the Iraqi army did not fight. Even the so-called elite Special Republican Guard units, well paid, well equipped and tribally linked to Saddam, went home. Television coverage and much of the newspaper coverage of the war was highly deceptive because it gave the impression of widespread fighting when there was none. I entered Mosul and Kirkuk, two northern cities, on the day they were captured with hardly a shot fired. Burnt-out Iraqi tanks littered the roads around Baghdad, giving the impression of heavy fighting, but almost all had been abandoned by their crews before they were hit.

The war was too easy. Consciously or subconsciously, Americans came to believe it did not matter what Iraqis said or did, though most Iraqis did not think of themselves as having been defeated. There was later to be much bitter dispute about who was responsible for the critical error of dissolving the Iraqi army. But at the time the Americans were in a mood of exaggerated imperial arrogance and did not care what Iraqis, whether in the army or out of it, were doing.

In those first months after the fall of Baghdad it was extraordinary, and at times amusing, to watch the American victors behave exactly like the British at the height of their power in 19th-century India. A friend who had a brokerage in the Baghdad stockmarket told me how a 24-year-old American, whose family were donors to the Republican Party, had been put in charge of the market and had lectured the highly irritated brokers, most of whom spoke several languages and had PhDs, about the virtues of democracy.

Most Iraqis were glad to be rid of Saddam. He had been a cruel and catastrophically incompetent leader who ruined his country. All Kurds and most Shi'ites wanted him gone. But it did not follow that Iraqis of any description wanted to be occupied by a foreign power.

There was a misconception among Iraqis about the depth of the divisions in their own society. Sunnis would accuse me of exaggerating their differences with Shi'ites, but when I mentioned prominent Shi'ite leaders they would wave a hand dismissively and say, "But they are all Iranians or paid by the Iranians." Al-Qaeda in Iraq regarded Shi'ites as heretics as worthy of death as the Americans.

The Sunni defeat in the battle for Baghdad in 2006 and early 2007 was the motive for many guerrillas, previously anti-American, suddenly allying themselves with US forces. They concluded they could not fight the US, al-Qaeda, the Iraqi army and police and others at the same time. There is now an 80,000-strong Sunni militia, paid for and allied to the US but hostile to the Iraqi Government. Five years after the US and British armies crossed into Iraq, the country has become a geographical expression.

Independent