Perceived Political Party Divide During the Pandemic: A Framework Linking Attitude Strength Toward COVID-19 Vaccines to Affective Polarization

Abstract This study examines how perceived political party divide may foster affective polarization during the COVID-19 pandemic. Drawing on nationally representative sample surveys of U.S. and South Korean adults, we investigate the relationship between attitude strength toward COVID-19 vaccines, perceived polarization, and affective polarization. Results suggest that individuals with stronger attitudes toward vaccines are more likely to perceive a greater ideological divide between political parties, which in turn, is associated with increased animosity toward the opposing party. Applying the mediation model to the South Korean sample yielded consistent findings, suggesting that the mechanism by which strong attitudes relate to negative emotions through perceived polarization may be generalizable across countries with a competitive two-party system, particularly in the context of COVID-19 vaccination attitudes. Our findings highlight perceived polarization as an important intermediary in the process of affective polarization, shedding light on the mechanisms driving partisan hostility in contemporary democracies.