Your apparent understanding of world history and especially American history is either wrong or incomplete. I doubt I have enough time (or desire) to convince you of anything. American slavery was different than what was practiced anywhere. Though the word wasn't mentioned until the 13th Amendment, slavery was embedded in the Constitution, the Electoral College, the Black Codes, Jim Crow, and modern voter suppression. I'll give you one place to start, if you have questions I'll be happy to enlighten you.

https://medium.com/discourse/partus-sequitur-ventrem-the-rule-that-perpetrated-slavery-and-legalized-rape-e3c423692bc2