FOUR years after the deadly 2001 anthrax attacks, which brought fresh terror to the US days after the September 11 hijackings, the biggest criminal investigation in American history has gone cold. The failure to solve one of the most baffling and sinister terrorist cases of modern times has not only led to intense frustration for the FBI, but has also prompted the British widow of one of the victims to sue the US Government. Bob Stevens, a British picture editor from Berkshire who worked in Boca Raton, Florida, was one of five people who died in and seventeen who became...