The sins of our fathers... Just because racism and violence still exist today does not mean we're all ignorant of the sins our ancestors committed and should abolish an economic system that tangentially benefitted. And this is not a modern phenomenon, as he seems to imply. This country was one of the first to abolish slavery. What occurred in this country's brief history pales in comparison to the brutality that came before it.
Slavery is institutionalized theft, organized crime. It is the opposite of free trade and capitalism. Sure, self-proclaimed "capitalists" owned slaves, but that shouldn't impugn the whole system. Please tell me, what other economic system has lifted billions out of poverty?