Mind over Metal: Public Opinion on Autonomous Weapons in the United States, Brazil, Germany, and China

Abstract Autonomous weapons exemplify the tension between technology and ethics in modern warfare. While observational studies suggest that the public holds negative attitudes toward the use of these weapons, experimental evidence from the United States shows that their acceptance is context dependent. This suggests that Americans may hold only a weak preference for “mind over metal,” and the aversion observed in polls may not reflect deeply held moral convictions. Yet, prior experimental research has focused exclusively on the American public, often relying on hypothetical scenarios featuring “terrorist” targets, which may inflate support. Consequently, it is unclear whether contextual factors such as the risk of target misidentification or enemy identity influence attitudes similarly in other countries. To address this gap, we conducted a preregistered survey experiment in the United States, Brazil, Germany, and China. Our results indicate that the public responds similarly to risk-based primes across countries, while enemy identity—terrorist group or aggressive state—has no significant effect. Notably, Chinese respondents expressed higher overall support than Americans, Brazilians, or Germans. These findings contribute to the literature on public attitudes toward emerging technologies and the cross-national generalizability of survey experiments.