From early morning, convoys of khaki trucks carrying paramilitary riot police rumbled into Urumqi. The troop carriers, interspersed with armoured personnel carriers, water cannons and multiple tear-gas launchers, disgorged their cargoes into the streets around Urumqi's People's Square, fanning rapidly out across the city centre. After Tuesday's chaotic scenes, where the Chinese authorities appeared to be taken by surprise when a 10,000-strong mob of Han Chinese took to the streets with axes, staves and knives, this was an unequivocal reassertion of the controlling power of state. As soon as curfew was lifted at 8am, the streets reverberated to the tramp...