Last year, when Darren Wilson, a white Ferguson, Missouri, police officer, fatally shot Michael Brown, an unarmed black man, the denizens of America’s liberal political swamp all shrieked “racist.” They implied that this happened because the officer is white, there were hardly any black officers on the police force, the police chief was white and five of the city’s six city councilmen are white. The city is 25 percent black.