ABSTRACT
Objective
Liberal democracies are under mounting pressure as citizens increasingly support policies that curtail fundamental rights. Prior research has often attributed illiberal attitudes to one partisan camp. We show that zero-sum thinking—the belief that one group or person’s gains necessarily come at another’s expense—is a powerful cross-partisan psychological predictor of such attitudes.
Methods
In a nationally representative survey experiment (n=2397$n=2397$), we asked respondents whether existential threats justify restricting fundamental rights under one of three randomized issue frames: climate change (a liberal issue), illegal immigration (a conservative issue), or no specific threat.
Results
We find that zero-sum thinking strongly predicts support for illiberal attitudes across all treatment conditions: an interquartile-range increase in zero-sum thinking is associated with an 11–13 percentage point increase in illiberal attitudes, regardless of partisan affiliation. Framing effects are confined to low zero-sum thinkers, who respond predictably to partisan cues: Democrats favor restrictions for climate change, while Republicans do so when they address illegal immigration. High zero-sum thinkers, by contrast, hit a “threat ceiling,” exhibiting uniformly high support for coercive measures with little sensitivity to partisan framing.