How many microaggressions can dance on the head of a pin?

It seems to me that the core dilemma of the Western world– let’s assume that many people on the Left still are in favor of freedom of speech and freedom of opinion, no matter how hateful– is how to ditch the extremists on their side without degrading, also, the ideals they began with.  For the Left, that’s fighting racism, sexism, et cetera– in their original definitions.  For sure as anything, the new definitions of those things– the definitions and ever-tinier distinctions, trending toward the question of how many microaggressions can dance on the head of a pin– is corrupting that ideology, and I think the more thoughtful people on the Left can sense that.

In this, they are discovering anew the dilemma that religious people have been struggling with for millennia.  How do you maintain idealism, protecting it from diversion, cooption or perversion by people interested mainly in power, or in getting to feel superior and righteous…or worst of all, both?  (It’s akin to the dilemma of stupid people in a democracy.)