Ten years ago Shaun Smith was an enforcer for one of the biggest crime families in Liverpool and embroiled in a war against a rival drug gang.Shaun introduced urban terrorism to the British underworld. He sprayed up houses with machine guns, tortured people and used homemade napalm to firebomb his enemies.Today, after a spell of five years in prison for firearms offenses, he is trying to transfer those skills to the legal economy by working as a debt collector in the northern English satellite town of Warrington.