The (de)polarizing effects of extreme political rhetoric

A large literature demonstrates that political elites are ideologically polarized: their policy-based beliefs have moved further away from the ideological center toward the left and right extremes, and they disagree today more strongly and more consistently on a variety of issues. When elites polarize, the likelihood that their communication will also be extreme is particularly high, either because their rhetoric reflects genuinely extreme beliefs or because polarized politics provides them with strategic incentives to appear extreme in the eyes of voters or journalists. To date, however, extreme rhetoric has not been conceptualized, and its effects on citizens have not been systematically examined. This omission is surprising given the extensive literature demonstrating that elite communication is a critical determinant of citizens’ political preferences. Drawing on psychological research into the nature of ideological extremity, we define extreme rhetoric as elite communication displaying intolerance, overconfidence, cognitive simplicity, or any combination thereof. With this definition in hand, we conduct a series of experiments assessing the effects of such communication on ideological and affective polarization in the electorate. Results reveal an interactive effect: extreme rhetoric from an out-party source polarizes the electorate, whereas extreme messages from an in-party source facilitate the adoption of more moderate attitudes.