Final answer:
Martin Luther King Jr. initially resisted but ultimately embraced the label 'extremist', redefining it in the context of historic figures who radically advocated for justice and aligning his nonviolent approach with an extremist position of love, truth, and goodness.
Step-by-step explanation:
Dr. Martin Luther King Jr., a central figure in the American civil rights movement, had complex feelings about the term 'extremist'. In his famous 'Letter from a Birmingham Jail', King initially bristled at being labeled an extremist by critics, but he ultimately embraced the term after contemplating the historical role played by extremists in the cause of justice. He recognized that many revered figures such as Jesus, the apostle Paul, Martin Luther, and Abraham Lincoln were considered extremists in their time for their radical advocacy. King stated that he had gradually come to the conclusion that the Negro's great stumbling block was not the White Citizen's Councillor or the Ku Klux Klanner, but the white moderate who preferred a 'negative peace'—the absence of tension—to a 'positive peace', which is the presence of justice. Thus, while he had reservations about the militant connotations associated with being an extremist, he compellingly reframed the term and identified himself as an extremist for love, truth, and goodness, aligned with figures like Jesus and other transformational leaders. King's nonviolent approach contrasted with more militant Black Power advocates like Malcolm X who endorsed the use of violence in self-defense and called for Black self-reliance.