1st Amendment Rights
I'm not quite so pessimistic as Kurt Anderson here, but he does get to the guts of why politics in America can be so wearying these days: Almost any argument about race, gender, Israel, or the war is now apt to be infected by a spirit of self-righteous grievance and demonization. Passionate disagreement isn’t sufficient; bad faith must be imputed to one’s opponents: skepticism of affirmative action equals racism, antiwar sentiment equals anti-Americanism (or terrorist sympathy), criticism of Israel is by definition anti-Semitic, and so on. More and more people think they’re entitled to the right not just to ignore or disapprove, but to veto and banish.