Political shocks asymmetrically consolidate right-wing communities on Twitter

Political psychologists have long argued that sudden, threatening events bring conservative political communities closer together, more than they unite people on the left. Here, we test this idea in real online social networks. We studied how people formed new social connections on Twitter in France and Sweden around 13 major political events between 2014 and 2021 – elections, scandals, and national crises. We show a clear and consistent pattern. After political shocks, right-wing populist communities tended to become more tightly connected with one another, while most other communities, including left-wing, media and centrist communities, changed less consistently. On average, populist-right communities became about 9% more connected than other groups. The cumulative pattern was strongest in Sweden, where these gains built up clearly over time. In France, the cumulative effect was weaker, but the populist-right community broadly maintained or slightly increased its internal cohesion while several other communities became more porous. The same broad asymmetry appeared in both countries, despite their very different political systems and parties. We therefore show that political shocks do not simply make everyone more divided. They can reshape the online political world around an increasingly consolidated populist right, while leaving other communities less consistently affected.