Their presence in central Basra was the single largest trigger for violence, according to Major General Graham Binns. "We thought, 'If 90 per cent of the violence is directed at us, what would happen if we stepped back?"' he said.
About 500 British troops moved out of one of Saddam Hussein's palaces in central Basra in early September, joining 4,500 at an outlying airport.
Since then there has been a "remarkable and dramatic drop in attacks", General Binns said. "The motivation for attacking us has gone, because we're no longer patrolling the streets."