Tarl Warwick does a great job condensing real American history regarding slavery and industrialization. At the height of slavery in America, 1.5% of the population owned slaves. It ended 150 years ago with the Civil War. Although I would add as a reason for the Civil War the fact that it was also about whether or not the new Western territories were going to have slavery or not and if they could be forced to return 'escaped' slave.
This 'race critical' theory is doing very deep damage to all the people who stood up against slavery and often laid down their life and property to put a stop to the grave injustice of it.
Of course if BLM were truly serious about stopping injustice and not just using their pointed fingers to blackmail for money (grifting), they would be addressing the ongoing current enslavement of millions of Africans, Indians and even many Polynesians across those same countries and in the Middle East.