Few people paid much attention when, late last month, Shabir Hussain and his friend Mohammed Shabir were jailed for 11 years at Birmingham Crown Court. Working with rudimentary tools in the basements of their homes, the pair had set themselves up as armourers to the local underworld, converting blank firing pistols into lethal weapons. They produced more than 170 guns and sold them to gangs from Bristol to Manchester. One week after the jailings, the murder of Nottingham jewellery shop owner Marian Bates, the gunning down of Hertfordshire gangster Dave King, and a drive-by shooting in Reading in which three...