And what do the ~120 million white Americans who don’t have black friends even say to convince us they aren’t racist?

I agree with much of this article, but I find the quoted sentence odd. Who constitutes the "us" in that sentence, and why should I care whether "us" is convinced? I don't answer to "us." If there is something wrong about wanting someone to be "an" anti-racist, isn't the same thing wrong about wanting someone to be a person with black friends? How can you rightly point to subcultural differences and not also recognize that most friendships are relationships between people who share subcultural ties?

From where does the presumption of animus arise? I don't have any friends who are dentists. Who do I need to convince that I am not whatever one calls someone who does not adequately respect dentists?