My take on Michaels is that he is largely speaking to the academic left which makes a fetish of all sorts of diversity, but continuously forgets to speak about issues of class as something structural rather than just another issue of identity politics. In other words they focus mostly on issues of representation rather than redistribution. This is the academics that would fully support any movement that was focused on anti-racism (or as Glen Ford calls it in the latest LBO, "the easter bunny" because it feels good to be so obviously on the right side of an issue), but sees any arguments about economics as either hopelessly outdated or pointless because, as someone told me the other day, "we live in a free market society and we're going to continue to live in a free market society" (the same person, on the other hand, had just given a speech in which they consistently branded any kind of economic thinking as "Marxist").
In this Michaels, may come off as a full-way asshole, but I think he makes a good point--again, more for the academics and activists who would focus on "anti-racism" in and of itself. That is, on people who fail to see (as you say) that these struggles are interconnected in a fundamental way and who focus only on the "thought crime" of being racist (and therefore engage in the sisyphusean task of eradicating it) rather than on the greater crime of using race or gender or liberalism any other ideological construct to justify material inequality and disenfranchisement (and therefore be forced into uncomfortable situations where they have to sound like, er, well, MARXISTS!) It is a combination of self censorship, self congratulation, and being enslaved by academic fashion and cultural ideology: unfortunately there are only so many ways to say it that don't make one sound like an asshole, but I'll be the first to admit that Michaels doesn't seem all that interested in avoiding that fate.
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