Social media use, political tolerance, and political polarization: A moderated mediation approach

This study proposes a moderated mediation model to understand how social media use influences political polarization through two competing mechanisms and how such mechanisms are conditioned by political tolerance. The model was tested with a survey data set of 1,200 Hong Kong residents after the prolonged Anti-Extradition Law Amendment Bill (Anti-ELAB) movement. The findings revealed that social media use was positively correlated with attitude and behavior extremity. Such polarizing effects were channeled through politically motivated selective avoidance behavior, but at the same time there were prominent depolarizing effects induced by increased network heterogeneity through social media use. More importantly, political tolerance could amplify the depolarizing effect of social media use. Social media users with high levels of political tolerance are more likely to have a heterogeneous social network, which further attenuates attitude and behavior extremity. In contrast, political tolerance cannot counteract the polarizing effect of social media use channeled through selective avoidance.