If you are going to abolish slavery, that opens up all these other questions: what system of labor is going to replace slave labor? What system of race relations is going to replace the race relations of slavery? Who is going to have power in the post-war South? The Emancipation Proclamation doesn't answer that question, but it throws [it] open.

A man working for wages his whole life is not really free. That is why Jefferson said, you have to own land. Southerners said, - and they weren't being hypocritical - they said slavery is the foundation of freedom because if you own slaves, you are freer yourself.

Whatever Lincoln's racial views, which are not totally modern and egalitarian in many ways, he believes blacks should have this natural right to improve their condition in life and slavery denies that to them.

Colonization was the idea that once slavery ended African-Americans should be encouraged - or required, in some people's view - required to leave the country. It's part of an attitude toward the abolition of slavery which says America should not be a slave society, but it can never be a multiracial society. You can never have free black and white people living together.

Freedom has been privatized - it is how you dress, what your sexual orientation is, choosing your own life. That's fine. But that is not what Thomas Jefferson was talking about.

A new future requires a new past.

You pick up very well-known books on Lincoln [and] you will find almost no reference to his long-term belief in colonization. Why? Because it doesn't fit the image of the Great Emancipator. It doesn't fit the retrospective view we want to have of Lincoln as the man who was the moralist in politics, who came into office committed to ending slavery and waited to sign this document.