In 1985, Stanley Greenberg, then a political scientist, immersed himself in Macomb County, a blue-collar Detroit suburb where whites had abandoned the Democratic Party in droves. He found that the Reagan Democrats there understood politics almost entirely in racial terms, translating any Democratic appeal to economic justice as taking their money to subsidize the black underclass.

And it didn’t end with the Reagan era. Piles of recent studies have found that voters often conflate “social” and “economic” issues.

What social scientists delicately call “ethnocentrism” and “racial resentment” and “ingroup solidarity” are defining attributes of conservative voting behavior, and help organize a familiar if not necessarily rational coalition of ideological interests.

Doctrines like neoconservative foreign policy, supply-side economics, and climate skepticism may bear little connection to each other at the level of abstract thought. But boiled down to political sound bites and served up to the voters, they blend into an indistinguishable stew of racial, religious, cultural, and nationalistic identity.