"White" America

An excerpt from a  Vox piece on biracial identity in America:

"Before the election, we found that white people thought he [Obama] was “too black” and black people found him to be “too white.”
Those perceptions shifted significantly after his reelection. Only then did white individuals see Obama as being “white enough” for them and black individuals see him as being “black enough.” This switch suggests people did seem to understand that he was biracial but found it easier to claim him as a racial in-group member once he became a success story."

 The author goes on to say we have difficulty with ambiguity, so like to simplify.

What that means to me is that's one method by which America will remain "white": as members of current "minority" groups become successful, they'll be assimilated into "us".