This is the very problem that's easily addressed by leveraging our own history more aggressively.
The United States is not 400 years old. The United States will be 400 years old in the year 2176, and we're nowhere near there yet.
These idiots who control the history departments are blaming the British Empire's slavery on us. That's what this number means. The Empire did this, not the United States. There's no reason why we should take the fall for it, they did it.
And as we’ve all witnessed- slavery was as much the sin of African kings as anyone else: https://www.youtube.com/watch?v=vNUZQNpWZ10