Martin Luther King Jr.'s "Letter from Birmingham Jail" is significant for its eloquent defense of nonviolent protest and its critique of racial injustice. Written while incarcerated for participating in protests, King articulated the moral imperative for direct action against segregation and discrimination. He emphasized the need for urgency in the civil rights movement, arguing that "justice delayed is justice denied." The letter provides a philosophical framework for civil disobedience and remains a key text in American history. Its profound insights on justice, morality, and the responsibility of individuals to stand against oppression continue to resonate today.