In an unfamiliar city it is rarely a good sign when your burly African-American taxi driver says: “I wouldn’t be driving you in this neighbourhood if it was dark.”

We are in Memphis, the most violent city in America. There were 397 homicides here last year in a population two-thirds t…

ncG1vNJzZmismJq3orPGsquhoaOpuaZ60q6ZrKyRmLhvr86mZqlnnKTDpnnAp5tmoJGlvaq6xKyqZqGeYsGpsYypnLCrXaSz