Go back far enough and your ancestors first masters were the blacks that sold them. There are no slaves here if nobody sold them. Columbus enslaved some natives and found they made terrible slaves, hence the need for Africans. While you're giving half assed history lessons, what percentage of Americans owned slaves? Why don't you whine about the Europeans that actually began the slave trade? Oh right, you can't convince them to give you anything. That would have been Spain, France, England, the Netherlands, and Portugal. Yet you simply lay the blame on whites, way to use the broad brush.
As to Jim Crow, place the blame on your Democrat predecessors, where it belongs. Same folks that tried keep slavery and gave you folks the Klan.
You can stop your whining now.