Presidential Address: Identity Politics
构建了一个基于内生社会身份的理论，解释政治极化维度的变化，发现政党传播刻板印象的激励是身份极化关键驱动，并用中国冲击导致的投票重组证据支持模型预测。
We offer a theory of changing dimensions of political polarization based on endogenous social identity. We formalize voter identity as in Bonomi, Gennaioli, and Tabellini (2021), but add parties that compete on policy and spread stereotypes to persuade voters. Parties are historically connected to different social groups, whose members are more receptive to the party messages. An endogenous switch from class to cultural identity accounts for three major changes: (i) growing cultural conflict between voters and parties; (ii) dampening of redistributive conflict, despite rising inequality; (iii) a realignment of lower class voters from the left to the right. The incentive of parties to spread stereotypes is a key driver of identity‐based polarization. Using survey data and congressional speeches, we show that—consistent with our model—there is evidence of (i) and (ii) in the voting realignment induced by the “China Shock” (Autor, Dorn, Hanson, and Majlesi (2020)).