Birds of a Feather?

Drawing on Haidt and Graham’s Moral Foundations Theory and computational text analysis, this article analyses 2,263 speeches delivered during the General Debate of the United Nations General Assembly between 1990 and 2023 to investigate the moral and emotional dimensions of populist foreign policy. Our findings reveal that populist leaders, irrespective of their nationality and political orientation, have developed a common foreign policy grammar that distinguishes them from other political figures. Their predominantly negative rhetoric emphasises moral values such as in-group loyalty, authority and purity, while non-populist leaders rely less on negative moral appeals, thus emphasising norms, co-operation and justice. Emotions such as anger and disgust are more prominent in populist discourse, namely among right-wing leaders. The values and emotions that underpin populist discourse contribute to the social construction of a less co-operative-prone environment, thereby hindering consensus-building initiatives and potentially weakening multilateral institutions.