Injustice anywhere is a threat to justice everywhere. We are caught in an inescapable network of mutuality, tied in a single garment of destiny. Whatever affects one directly, affects all indirectly.

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

Letter from Birmingham Jail (16 Apr 1963)
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Another phrase King used on repeated occasions, e.g., "Injustice anywhere is a threat to justice everywhere. Therefore, no American can afford to be apathetic about the problem of racial justice. It is a problem that meets every man at his front door" -- "The Rising Tide of Racial Consciousness," Speech, National Urban League, New York (6 Sep 1960).