What accounts for the movement of many African Americans from Dr. King's " beloved community" ideal to the "black power" slogan popularized by Stokely Carmichael and H. Rap Brown?

Numerous factors contributed to the shift from MLK's vision to the "Black Power" movement highlighted by Stokely Carmichael and others. Coinciding with the nonviolent mass protests that MLK and others lead in the South in the early 1960s was a growing movement amongst people like Malcolm X and the Nation of Islam. They thought King’s nonviolent approach was too gradualist, integration was unworkable, and political efforts did little to solve economic and social problems faced by blacks. Malcolm X instead encouraged a cultural revolution among blacks and condoned self-defense, in contrast to King and others's commitment to absolute nonviolence.
These principles of self-defense and black pride and independence gained more traction in the mid-1960s. In part, this was due to the successes of King's movement. With passage of Civil Rights Act of 1964 and Voting Rights Act in 1965, attention moved from the South to northern cities and centered on racial discrimination in housing and employment. King's approach failed to gather the attention in the North that it had in the South. In addition, there was increased racial violence in cities and increased disillusionment of many blacks with peaceful change. In 1966, Stokley Carmichael made "black power" a catchphrase for this shift in the Civil Rights Movement when he proclaimed, I ain’t going to jail no more . . . We been saying freedom for six years and we ain’t got nothin’. What we gonna start saying now is Black Power!
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