Every famous black comic who’s ever performed in a club or a concert hall (Chris Rock, Richard Pyror, Eddie Murphy, Bill Cosby, Bernie Mac…anyone) has joked about dorky white-people behavior, and every time they do this white audiences throw their heads back and howl. I’ve been to clubs and concerts, seen this time and again. Whites love being lampooned because there’s obviously some imbedded truth involved (as with all good humor) and it’s a relief to just kick back and recognize it. And yet Barack Obama describes his white grandmother in candid, matter-of-fact terms as a “typical white person” — i.e., suspicious and uncertain where black folks are concerned — and he gets jumped on by the TV commentators.