Particularly the sentence "And that is not to speak of the lethal counter-enthusiasm, the ugly, race-tinted hatreds also provoked by the election of the first black president, the dogs baying on the White House lawn."

That there are "ugly, race-tinted hatreds" among certain Americans towards Obama is clear, but that's a small minority, and that sentence really does sound a lot like she's accusing Obama's opponents or detractors in general from having racist sentiments. Especially in combination with the sentence before that, which suggests that it's not Obama's fault that he's doing such a mediocre job as president so far.

And I've no idea if birthers call themselves birthers, probably not.