I did read Harvey’s book, which is how I happened on those passages. Harvey’s essential line is about the way identity politics work against solidarity.

Identitarianism is an ideology that liberals are especially susceptible top — it’s no coincidence that a liberal, Kiimberle Crenshaw, came up with the concept of intersectionality to divorce racism and sexism from capitalism. I strongly recommend you try Racecraft by the Fields sisters or look at some pieces by Adolph Reed on the subject.