Reassuring Ally: The Source of Credibility of Extended Nuclear Deterrence

• In Event: Nuclear Politics in an Age of Mis- and Disinformation

Abstract

What shapes a public’s perception of the credibility of extended nuclear deterrence in a client state? While previous research has typically emphasized what a patron state does and says in its costly signaling behavior, this paper claims that contextual factors can contribute to the credibility of extended deterrence as well. Specifically, I claim that contextual factors such as a patron’s domestic situation and its general alliance/nuclear policy position can shape the credibility via several channels, such as the perceived likelihood of nuclear war. I test this claim using survey data collected in South Korea. The findings show that contextual factors indeed matter in shaping the mass perception of the credibility of extended deterrence. In particular, U.S.' quality of democracy and U.S. nuclear posture have a strong boosting effect on the perceived credibility of the U.S. nuclear umbrella among the South Korean public.

Author

• Jiyoung Ko, Korea University