It is a trite yet urgently true observation that if America is to remain a first-class nation, it cannot have second-class citizens.

Martin Luther King, Jr. (1929-1968) American clergyman, civil rights leader, social activist, preacher

“The Negro and the American Dream,” speech, North Carolina NAACP, Charlotte (1960-09-25)
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King used this line in several of his speeches at the time.