Intergroup Hostility in the Public Sphere: Systematizing the Rising Concern for Affective Polarization Beyond Partisan Lines

Initially conceived to describe a phenomenon between political parties, the concept of affective polarization is increasingly extrapolated to analyze relationships among other identity groups. This reflects a long-standing interest in intergroup relations within public opinion studies and calls for a broad theoretical framework that considers many ingroup/outgroup categorizations as potential disruptors of public sphere processes. By implementing a comprehensive and systematic review of peer-reviewed research on affective polarization (N = 458), we find that nearly one-third of publications extend the concept beyond political parties to encompass divides such as opinion-based, ideological, racial, territorial, and religious identities. After identifying key points of convergence and divergence between interparty and beyond-party research, we conducted a metatheoretical analysis of works that go beyond parties (N = 142) to classify the social groups potentially subject to affective polarization, the factors influencing the public salience of such identities, and the predominant observation methods and measurements. The results support a more dynamic understanding of identity salience in the public sphere and highlight challenges related to terminology and methodological compatibility across different approaches. Overall, the study reveals a growing interest in various forms of intergroup hostility that connects to broader contemporary concerns about democratic values.