Reward-based or threat-based deterrence: US policy toward Japan and South Korea in comparative perspective

Abstract

Despite the striking similarities in strategic environment of Japan and South Korea, US deterrence through nonproliferation policy toward the two allies varied in terms of its measures applied: reward-based deterrence and threat-based deterrence. Using the critical junctures framework, this paper argues that 1) domestic structural circumstances of divided with idealist bias or unified with realist bias in two allies led to different local responses to US policy that signalled the level of credibility of US security guarantee; 2) intermediaries that played a critical role in promoting mutual trust and confidence have influenced the credibility and confidence on intra-alliance level; 3) this credibility and confidence had shaped the direction of the US deterrence strategy of reward-based deterrence for Japan and threat-based deterrence for South Korea.