Ammar winds up a ten-minute harangue against Saddam Hussein with questions to his students. “How many of you had relatives executed?” asks the 33-year-old history teacher. Eight put up their hands. How many lost relatives in the Iran-Iraq war? Twelve hands rise. How many think Saddam was a bad man? All 24 students assent.

Their sincerity, though, is hard to gauge. This is no normal class, despite the Harry Potter books in Arabic on the shelves.

Ammar’s pupils wear bright yellow jumpsuits with plastic sandals and white identity bracelets around their wrists. They are among the rapidly multiplying number of child fighters held in the Camp Cropper detention centre near Baghdad airport.

The children, who are aged between 11 and 17, stand accused of offences ranging from acting as lookouts for kidnappers to planting bombs and shooting soldiers. The US military is sending them to school to reeducate them, to rid them of jihadist cant, to clear their brainwashed heads of, for example, the notion that Saddam was a glorious leader who defied an evil and aggressive superpower .

“We want them to be able to think for themselves so they’ll pick up a book instead of an AK47,” says Brigadier General Mike Nevin, the centre’s commander.

Iraq’s children are among the worst victims of the war, a generation brutalised and traumatised by the constant violence.

The detention centre is a daunting place for a teenager. Dubbed Remembrance II or R2, is a maze of formidable five-metre-high (17ft) mesh fences topped by coiled razor wire, floodlights and watchtowers. From metal catwalks armed guards look down on concrete-floored pens where surly detainees in yellow jumpsuits linger outside their huts in the baking heat. Nobody has escaped yet.

There are 4,000 male detainees in R2 and, with President Bush’s troop “surge” in full swing, 60 more arrive each day. There are separate zones for Sunnis, Shias, foreign fighters, moderates, extremists, adults and juveniles. Roughly 85 per cent are Sunni. A quarter are diehard jihadists determined to continue their war against the infidel Americans even while in custody.

The hardliners hold Sharia courts, beat fellow detainees for smoking, listening to music or participating in US programmes. They start fires. They foment riots. They hurl water bottles filled with urine at the guards, and “chai rocks” made of tea and dust moulded into hard round balls. They fashion knives from fragments of razor wire or the ground-down ends of toothbrush handles. They make slingshots from soccer ball linings and whips from strips of towel. Occasionally detainees are murdered by their peers – earlier this year a 17-year-old was strangled.

The US has realised belatedly that the detainee population is a rich recruiting ground for the fanatics. It now strives to isolate the real hardliners – during riots guards fire paintballs at the ringleaders so they can be identified later – while wooing the rest with offers of paid work, “antiextremist enlightenment programmes” that include lessons from moderate imams and enhanced prospects of release.

But total segregation is impossible. The extremists do not advertise themselves. Some will shave their beards to blend in with the rest. And “rock mail” – messages wrapped round stones – permits the passing of orders and threats from one compound to another. “They are very determined. They never give up,” says General Nevin.

With the 828 juvenile inmates, however, the military is making an extra effort. It does not want them released after a year to become next year’s suicide bombers.

It judges a hundred or so to be beyond redemption, but the rest are now bussed daily to a new school outside R2 called Dar al-Hikmah, or Wisdom House.

The school is a row of prefabricated sheds ringed by blast walls. Here the inmates receive eight hours of lessons a day. They are taught to read and write, they play soccer and basketball, they have Iraqi civilian teachers and security is markedly more relaxed. “We’re trying to take them away from the environment they have at R2,” says Captain Ali Dipour, the principal.

The school has only been open a month, but General Nevin and the teachers say that it is working already. They say that the children’s hatred and anger is dissipating; that Sunnis and Shia teenagers are beginning to mix, that they no longer chant the names of Osama bin Laden or Moqtada al-Sadr at prayer or hurl abuse at their teachers. Leyla, the only woman teacher, says that the boys see her as something of a mother figure.

The claims are hard to test, but the classes certainly look orderly and the students attentive. As in a million other schools around the world, the walls are decorated with childish crayon drawings of animals, trees, houses and stick-figure humans. “They are just kids wanting to be kids,” says Captain Dipour.

Time will tell; but it is just conceivable that in this grim detention centre, some of these child fighters are enjoying a taste of normality for the first time in their lives.

— The number of American troops in Iraq could be reduced to about 100,000 by the time the next president takes over in 2009, Robert Gates, the US Defence Secretary, indicated yesterday.

Casualties of war

2m Iraqi children displaced by fighting

800,000 children receive no schooling

28% of children are malnourished

6 children, aged 10 to 15, are treated each month by US medics after planting roadside bombs

828 juvenile detainees are in Camp Cropper, up from fewer than 100 last year

Sources: Unicef, Save the Children, Oxfam, US military

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