Under the Umbrella: Nuclear Crises, Extended Deterrence, and Public Opinion

How robust is public support for extended nuclear deterrence in patron and client states? Recent studies have improved scholarly understanding of US opinion about weapon use against non-nuclear adversaries. Yet, there limited knowledge attitudes regarding retaliation strikes allies. We develop a theoretical typology crises investigate this phenomenon with novel survey experiment ( n = 6,623). Americans, Japanese, South Koreans viewed realistic emergency alert messages most-likely case retaliation: North Korean missile attack on ally protected by the umbrella. Support low all three countries, important cross-national differences. Favorability increases first-use, but it remains nonetheless. Surprisingly, “tripwire” troop casualties do not increase Americans’ demands retaliation. These findings implications study practice deterrence.