One criticism of Nia-Malika Henderson's article on Obama's "dogwhistling" is that many of the cultural markers that Henderson takes as black are either generational, or things that whites understand. The first thing that should be said is that blacks also heard Reagan's dogwhistles--it's not like we didn't know what he meant by "states rights." But more to the point, we went through this a few months back when Obama gave his wife a pound after he secured the nomination. The argument, again, was that this wasn't anything "black" because "everyone" does it. I think this argument originates from the idea that black is the perfect and exact opposite of white. Historically whiteness has meant exclusion (though this may be changing) and so when whites hear that something is labeled "black," they may think "not for me."
But of course blackness isn't the perfect opposite of whiteness--black is not simply a racial identity, it's also an ethnic identity. So, in much the same way that Jews are, in this country, racially white and ethnically Jewish, blacks are "racially" black and--in the main--ethnically "African-American." This can get hazy when we start factoring in diaspora influences, but the point is that blackness, for black people, isn't a matter of being born, simply with a certain skin color. Indeed, in some cases, it isn't that at all. It's about practices--the way we eat, the way we live, the way we walk. It doesn't mean that all black people participate in this, nor does it mean white people can't participate in it.
Unlike white racial identity, African-American (and diaspora) cultural identity wasn't created (in most cases) to keep white people out. Hip-Hop wasn't invented so that white people wouldn't buy or participate in black music--quite the opposite. Henderson's article refer to cultural markers in the black community. That many white people (but evidently not many white journalists) understand these markers, and have adopted them themselves doesn't change the origin of said markers.
Thus claiming that Barack Obama saying "We straight," isn't black because white people get it, is like claiming enchiladas aren't Mexican because all the black people I know love them. Oy is still Yiddish--no matter how many non-Jews use the expression. These things tend to overlap, and allowing for the differences between a racial blackness and a cultural/ethnic blackness, we can see how a pound can be an African-American invention, and yet still be an act performed by the Duke lacrosse team.
For the record, I think this is one of the reasons why blacks and whites tend to talk past each other. We need to avoid this lazy idea that black is simply the opposite of white, and be conscious of when we're discussing ethnic identity, racial identity or both.