> It already is taken as fact in many circles

You can really say this about anything. Not that I am disagreeing with you, but it’s a dubious way to frame anything you wish to state.

Sure, I agree it isn't very specific, but I wasn't trying to make a general claim, just provide a hopefully recognizable example of revisionist history.

I think it would be different if I was claiming that most people believe this narrative, or something like that.

I could have pointed to some specific academics who feel this way, but I'm not sure that is any more convincing. Basically any example can be ignored with a no true scottsman argument if someone is obstinate instead of curious.

Can you please provide a (credible or somehow representative) source claiming that the primary purpose and intent of the American legal system and government was the subjugation of minorities.