Favoring ingroups, derogating from outgroups: how populist parties in Belgium polarize on social media

 

Abstract

In a context of increasing polarization, this study proposes to clarify the way populist parties cultivate vertical (people vs. elites) and horizontal (between different groups in society) opposition in their online communication. Relying on Social Identity Theory (SIT) and on the concept of claim of representation, this article investigates to what extent left-wing (LWPP) and right-wing (RWPP) populist parties in Belgium create antagonisms in their online communication. Expectations are threefold. First, ingroup appeal and outgroup derogation should be more present in social media messages of populist parties than in non-populist ones. Second, both LWPPs and RWPPs should oppose groups vertically as well as horizontally. Third, the nature of these groups should be conditional upon their respective ideology—namely, socialism on one side, and nativism on the other. To this end, the article analyzes 13 months of X posts by all 13 parliamentary parties and their presidents (N = 12,303), during a routine period (January 2023–January 2024). Our findings first reveal that populist parties, and especially RWPPs, are more likely to resort to outgroup derogation compared to non-populist parties. Second, regarding the vertical antagonism, our analysis points out the intertwined effect of populism and incumbency. Third, the nature of group appeals greatly differs between LWPPs and RWPPs, in connection with their core ideology.