Decentralized yet Unifying: Digital Media, Normative Crowding Out, and Solidarity in Hong Kong's Anti-Extradition Movement

Can decentralized, digitally-enabled movements sustain solidarity over time? What is the role of digital media in such a process? Existing studies point to the tendency of such movements towards fragmentation. We focus on the case the 2019 Anti-ELAB Movement in Hong Kong and one of the primary digital platforms for mobilization, LIHKG. We argue that LIHKG users maintain the dominance of solidarity through a strategy of normative crowding out, whereby users strategically promote solidaristic rhetoric and emotions while sanctioning divisive ones. Empirically, we analyze millions of discussion posts on LIHKG with rich text and emoji data. We first document the rising trend of online solidaristic contents despite contemporaneous tactical radicalization. Regression analyses further show that such a pattern can be produced by user-driven mechanisms in sanctioning solidaristic and divisive contents. This study has implications on the role of digital media and the sustainability of decentralized collective action.