“Once U.S. prisons are recognized to be a system of enslavement, and the lie is exposed that slavery in Amerika was ever abolished, the abusive conditions that pervades them makes perfect sense.”

1960s, The Role of the Behavioral Scientist in the Civil Rights Movement (1967)

Reagan
Song lyrics, R.A.P. Music (2012)

The honour of the States, as well as justice and humanity, in my opinion, loudly call upon them to emancipate these unhappy people. To contend for our own liberty, and to deny that blessing to others, involves an inconsistency not to be excused.
1780s, Letter to R. Lushington (1786)

Source: The Political Thought of Abdullah Ocalan (2017), Liberating Life: Women's Revolution, p. 69

1770s, African Slavery in America (March 1775)

1960s, Where Do We Go from Here: Chaos or Community? (1967)
Context: As long as the mind is enslaved, the body can never be free. Psychological freedom, a firm sense of self-esteem, is the most powerful weapon against the long night of physical slavery. No Lincolnian emancipation proclamation or Johnsonian civil rights bill can totally bring this kind of freedom. The negro will only be free when he reaches down to the inner depths of his own being and signs with the pen and ink of assertive manhood his own emancipation proclamation. And, with a spirit straining toward true self-esteem, the Negro must boldly throw off the manacles of self-abegnation and say to himself and to the world, "I am somebody. I am a person. I am a man with dignity and honor. I have a rich and noble history, however painful and exploited that history has been. Yes, I was a slave through my foreparents, and now I’m not ashamed of that. I'm ashamed of the people who were so sinful to make me a slave." Yes, yes, we must stand up and say, "I'm black, but I'm black and beautiful." This, this self-affirmation is the black man's need, made compelling by the white man's crimes against him.

Speak, Memory: A Memoir (1951)

As quoted in [McInerney, Daniel John, The Fortunate Heirs of Freedom: Abolition & Republican Thought, https://books.google.com/books?id=ZrnV5Rj6eckC, 1994, U of Nebraska Press, 0-8032-3172-5, 83-4]

Speech in Wisconsin, March 26, 2000. http://renewamerica.us/archives/speeches/00_03_26wi.htm.
2000