Martin Luther King Jr. was assassinated on April 4, 1968. Half a century later, King remains one of the most vivid symbols of hope for racial unity in America. But that's not the way he was viewed in the last years of his life.
During this time, King's message had become more challenging and pessimistic. He spoke passionately against the Vietnam War, which at the beginning of the fight was still far to the left of what most Americans thought.
His opponents criticized him for stepping out of his realm of expertise, civil rights, and claimed that in doing so he was undercutting the efforts of African-Americans.
But King believed that being morally wise sometimes meant being politically unwise.
In 1962 the FBI, under J. Edgar Hoover, began spying on King, suspicious that he and his movement were being influenced by communists. King was aware of the observation. On one occasion, he found a microphone at the pulpit while he was giving a sermon and addressed whoever was listening directly before continuing.
By 1967 though, King had much more difficult things to deal with. Violent riots were spreading in black communities around America, as people there became fed up with poverty and police repression.
King's message of nonviolence went largely ignored by other black leaders, and thus King's speeches became more and more defeatist.
Those close to him saw that he wanted to quit, emotionally drained from what he saw as setbacks in the civil rights movement. But instead of taking a sabbatical, King renewed his efforts, this time focusing in on the struggle for economic justice — asking for a redistribution of wealth. This was an idea many considered radical, including the FBI which continued work to smear King's reputation.
In 1968, King attempted to lead a peaceful march after the death of two Memphis garbage collectors. Despite his efforts the march turned violent, and the FBI as well as the news media took it as a sign King was losing authority among his followers.
Later that same year, King was assassinated. Hundreds of communities around America erupted in violence at the news, his death igniting new fury in the African-American community.
APM Reports and American RadioWorks put together a documentary on King's final years, produced by Kate Ellis and Stephen Smith, called "King's Last March."
To listen to the documentary, click the audio player above.
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