I agree with all those except Abraham Lincoln. Freeing the slaves was done not out of any sense of altruism but fulfilling a threat.

Hell, I'm black, but even I will concede that the South had a right to secede the Union.

Ali was a hero because he stood up for what he believed in despite his livelihood nearly being ruined and almost going to prison. He was very key in turning the tide of opinion against an unjust war.

Malcom X was a hero because he broke away from the people who brought him into prominence to pursue something more pure than what he was taught. He also died for what he believed in.

Martin Luther King for wanting something better for all people, not just his own. And for dying for what he believed in.