"Ruined" made sense to me. I think there are probably dozens of words you could use for what you were trying to say. "Ruined" might not be the first choice a writer would maker, but as far as conversation goes, it was perfectly understandable to me.

You could also say that stereotypes are erased, destroyed, eliminated, melted, damaged, disintegrated, blown away, eradicated, or mutilated! LOL

I think America has plenty of it's own racism. Obama's presidency has proven that. Racism in America is like an infected wound and Obama's election ripped off the band-aid - exposing all that nasty gangrene to the fresh air and to the eyes of the world.