Has it? I saw the Broncos parade in Denver, not a Browns parade in Cleveland.
Without having any insight into what you might have in mind, since the majority of Americans have been white Christians, it stands to reason that, if for no other reason than random chance, a given victim is more likely to have suffered at the hands of a white Christian than any other racial-religious combination in America.
Do you consider Harriet Tubman to be a national hero? Is she deserving of celebration as a national icon, to represent positive values of the United States?
Do you think that slaves in the United States were victims of oppression?
At what point do you think the social and economic consequences of slavery on persons of African American descent ceased to be an impediment on their ability to advance en masse in the United States?
Give me your choice. I agree this is a very politically correct choice but, beyond that, you've read this entirely wrong. Had they selected James Madison instead, the race issue would be very much front and center as to why another white male was chosen in the most diverse first world nation the world has ever known.
It isn't. I try not look for an opportunity to denigrate someone. Can you make a list, in your order of preference, of who you would like to see appear on the $20 bill? This isn't in an effort to label you as being racist; I want to see where Harriet Tubman would fall on your list. I think she's an excellent choice because it's almost universally agreed that slavery is massive and unforgettable black eye in American history and she is legend for the extent she risked her life to help people escape bondage and find freedom. She's a hero. Why does inclusiveness bother you so much (and I apologize in advance if it doesn't and I've grossly misread your writing)?
You can find anything on the internet.
I disagree.