Do External Threats Reduce Affective Polarization? An Experiment on Russia's Invasion of Ukraine

Abstract

In many countries, partisans have become increasingly biased in how they evaluate others based on political affiliation. We suggest that this increase in affective polarization may in part be caused by changes in the global power distribution which caused many countries to experience a long period without external (military) threats. To study the importance of external threats, we conduct a priming experiment to examine how making Russia’s full-scale invasion of Ukraine in 2022 salient causally influences affective polarization and collaboration in the U.S. We find that priming Americans with Russia’s military aggression leads to a modest reduction in affective polarization and an increase in cooperativeness as measured by behavior in an incentivized coordination game. Surprisingly, the effect of making Russia’s invasion salient does not depend on perceived cross-party disagreement about the conflict. These results suggest that researchers should also consider international relations to understand within-country polarization and willingness to collaborate.