If Alice robs a jewelry store and sells the stolen jewelry to Bob and Dave, Bob still owns stolen jewelry. Legally, it doesn't even matter whether Bob knew the jewelry was stolen or how much Dave bought.
But that's leaving aside the gaping hole in your argument. We have decided as a society that no human can be the property of another. Thus, we don't speak of "buying" "trading" or "stealing" people, it's all just kidnapping. I'm not saying that the African tribes were saints (they weren't) or that Europeans didn't have slaves (they totally did, and they were pretty mean to them). But we live in the U.S.A, here and now. Part of our society is at a systematic disadvantage, due to the history we've already discussed. That is making our country poorer, and above all it's morally wrong.
Typical, going on some tangent off subject. If you want to argue the point offered, a little clue, the key word is kidnapped.
If Alice robs a jewelry store and sells the stolen jewels it's still Alice that robbed the store.
the comment presented was a point that 99% of the anti slavery people get WRONG. The Europeans didn't run through the jungles capturing the natives. They purchased them. Then they sold them to the world, not just America. Yeah, it's a world widw issue, not just local.
If you want to debate a point you need to know what you are talking about.
I know there are a lot of bigoted fots in my family's history. I also happen to know none of them had slaves. They were all too poor to own slaves.