Iraq is full of sad memorials to Britain's disastrous invasion of the country in the First World War. In military cemeteries along the Tigris and Euphrates are buried some 31,000 British and Indian soldiers who died in battle or of disease in four years fighting.
I used to visit one cemetery in Kut where a British army of 9,000 surrendered to the Turks in 1916. The swamp water had submerged the graves, leaving only the tops of tombstones protruding out of the green slime.
The second and equally ill-judged British intervention in Iraq, this time as an ally of the US, which started in 2003, looks as if it is going to be slightly shorter than the first. By the end of 2006 the new Iraqi Prime Minister, Nouri al-Maliki, says that US and British troops will have handed over security to Iraqi forces in 16 out of 18 provinces.
In fact 8,000 British troops could be withdrawn even earlier since there is no reason for them to stay in Basra, which they do not control and where they are likely to take casualties. Inside the city the militia are already predominant. The motive for British soldiers staying is presumably so the US can have at least one ally with troops on the ground.
Why was Mr Maliki more assertive about the timetable for withdrawal than his predecessors? Certainly he needs to offer something concrete on a US withdrawal to Sunni members of his government. Tariq al-Hashimi, the Sunni Arab Vice-President, said that "there have been real signs by the US and British governments that a decision was taken to withdraw foreign forces". He said this was enough for the armed resistance to talk to the US about the withdrawal and the role to be played by the insurgents after it is complete.
A word of warning here: one of the many problems of bringing peace to Iraq is that the Sunni community, though it launched a ferocious guerrilla war against the occupation which killed or wounded 20,000 US soldiers, does not have a coherent leadership, unlike the Shia and the Kurds. There is little sign that elected political leaders like Mr Hashimi can do more than plead with the insurgents.
But his overall point is important. Opinion polls have consistently shown that an overwhelming majority of Iraq's five million Sunni Arabs support armed attacks on US forces. This figure may wobble a bit as some Sunni look for American protection against Shia death squads, but overall the Sunni remain against the occupation.
There are now signs that the Shia, totalling 60 per cent of Iraqis, also want to see the occupation ended sooner than seemed likely six months ago. The US has become a major obstacle to them using their election victories last year to get a permanent grip on power in Baghdad. The US sided with the Kurds and the Sunni in forcing out the former prime minister Ibrahim al-Jaafari, though it was not able to divide the Shia coalition permanently.
The US and British armies in Iraq have both failed, though they could argue that the root of the failure is political rather than military. Three years after the overthrow of Saddam Hussein, they control extraordinarily little territory. Watching American forces in Baghdad since 2003, it always seemed to me that they floated above the Iraqi population like a film of oil on water.
Shia animosity towards the American and British forces is now beginning to look like that of the Sunni at the beginning of the guerrilla war. In Basra, crowds spontaneously dance and cheer when a British helicopter is shot down, just as the Sunni used to celebrate the destruction of every US Humvee in Baghdad (even then Tony Blair and George Bush claimed that the insurgents were just a small group of foreign fighters and Saddam loyalists).
The problem about the withdrawal is that it may be coming too late. The White House and Downing Street never took on board the sheer unpopularity of the occupation and the extent to which it tainted the Iraqi government, soldiers and police in the eyes of ordinary Iraqis. The Iraqi army and police are 230,000 strong, and this figure is due to rise to 320,000 men by the end of next year. But in reality the allegiance of these forces is to the Sunni, Shia and Kurdish communities, and not to the central government. The problem has always been loyalty rather than training.
The US and British armies in Iraq are becoming less and less relevant to political developments good or ill. Their presence is not acceptable to most Iraqi Arabs. They clearly cannot stop a civil war that has already started in the centre of the country. The main reason for keeping them there is to avoid a scuttle which would look like America's last days in Vietnam.