Hard disagree here. This is *primarily* due to racism. People have been trying to tell everyone
for years now that
this was never about "economic insecurity." I'm actually embarrassed for
these authors who can't quite suss out the common thread between wealthy white suburbanites and Proud Boys

, and think they're warning of a "new" kind of American extremist, when it's the same old rotten racist American extremist (astronaut meme here). White supremacist movements will inevitably lead to violence because it's rooted in the same pathological sense of entitlement, NOT because people don't tiptoe around their racial derangement or pay proper attention to them. Its periodic insurgence* is a
result of appeasement or the outright coddling they get, either from white supremacist political figures or Democrats who get suckered into imagining they're victims of circumstances and try to "reach out" and "understand" them. These are not people inexplicably voting against their own interests--as Isabel Wilkerson notes: “Why are people voting against their own interests, willing to elect right-wing oligarchs, forgo health insurance, risk contamination of the water and air? What had not been considered is the people voting this way were, in fact, voting their interest. Maintaining a caste system as it had always been was in their interest.” LBJ said something similar (and significantly more crudely) ~55 years ago. Republicans have been milking white people's self-inflicted psychic "wound" hard since (at least) Pat Buchanan encouraged Nixon to get more white voters by telling them how much black voters liked Democrats. This is an old ugly phenomenon whose lifeblood is narcissistic victim-whoring, and it should be hounded to the far reaches of society, until people learn better and are capable of rejoining humanity by demonstrating they can live in peace with their neighbors.
ETA: Meant to say
resurgence, but I think I'll leave it.