How Does Political Tolerance Moderate the Effects of Social Media Use on Political Polarization: A Moderated Mediation Model

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 of 1,200 Hong Kong residents after the prolonged Anti-Extradition Law Amendment Bill movement. We found that social media use was positively correlated with attitudinal and affective polarization. Such polarizing effects were channeled through politically motivated selective avoidance, but there were noticeable depolarizing effects induced by increased network heterogeneity. More importantly, political tolerance could further amplify the depolarizing effects of social media use. In contrast, political tolerance cannot counteract the polarizing effect of social media use channeled through selective avoidance. © The Author(s) 2023.