Muqtada leads the only real mass movement in Iraq. It's a mass movement of the Shia, who are 60 percent of the population, and of poor Shia - and most Shia are poor. Otherwise the place is full of sort of self-declared leaders, many of whom spend most of their time outside Iraq.

Everything that happens in Iraq affects countries outside.

There are some things that could hold it together, notably oil revenues. But at the moment, the much vaunted surge has had a measure of success primarily, to my mind, because Sunni and Shia Iraqis hate and fear each other more these days than they hate and fear the Americans.

There are sort of Kurdish districts there in Mosul, or there used to be, but the Kurds mostly fled or were driven out. The same is true of the Christians.

It's always sort of amazing, sitting in Baghdad, to watch visiting dignitaries being received in the Green Zone by politicians who have usually very little support and seldom go outside the Green Zone.

Despite the fact that there's billions of dollars sitting in the Iraqi government reserves, somehow they are incapable of getting it out to the people. There are a very large number of people here who are on the edge of starvation. For those sort of people - a sizable chunk of people - that service makes them regard Muqtada as a sort of god.

Young Shia who have been brought up with nothing, who are pretty anarchic, pretty dangerous. In 2004 when they came close to killing me, and of course they have killed very large numbers of other Iraqis. That's a major source of strength for Muqtada.