Generational Imprinting: How Political Events Shape Cohorts

How, and for whom, do political events translate into enduring political change? This article advances a theory of cohortization, where people's responses to a political shock are a joint function of whether they are in their impressionable years and their partisan identities. Focusing on the killing of George Floyd and the Black Lives Matter protests in the summer of 2020 as a quasi-natural experiment, I study the processes of cohort formation by analyzing attitudes toward U.S. law enforcement among non-Hispanic White Americans across multiple national surveys which collectively span from 2016 to 2024. The findings consistently show that Democrats and Independents became strongly unfavorable toward law enforcement, a pattern visible much more so among younger than older individuals. Moreover, the changes persisted for younger individuals, while fading among older individuals, leading to cohort-led polarization. In the end, this article provides a microfoundation for the political construction of generations.