Last week in Denver, almost all the values of the post-1960s Left were exhibited in one act. It happened on the Denver mayor's most important day -- the one in which he was to deliver his annual State of the City Address. The day was to begin with the singing of the National Anthem by the black jazz singer Rene Marie. But Ms. Marie had, by her own admission, long had other plans. Instead of the National Anthem, she sang "Lift Ev'ry Voice and Sing," a song written in 1899 and often referred to today as the Black National Anthem....