Conclusion

On August 28, 1963, during the height of the civil rights movement in the United States, there was the March on Washington.  It was at this event that Martin Luther King, who, at that time was the leader of the African-American Civil Rights Movement, gave his famous "I Have a Dream" speech.

"Watching the whole thing on TV in the White House, President John F Kennedy, who had never heard an entire King speech before, remarked: 'He's damned good. Damned good.' Almost everyone, including even King's enemies, recognised the speech's reach and resonance. William Sullivan, the FBI's assistant director of domestic intelligence, recommended: 'We must mark him now, if we have not done so before, as the most dangerous negro of the future of this nation.'" 

Consider why someone who was advocating for racial equality was seen as dangerous.