Solidification of the ROK-US Alliance Amid Conflict : Concerns of Alliance Risks Due to the Potential Nullification of the Nuclear Umbrella Commitment

South Korea and the US have been allies for over 70 years, navigating numerous political interests and conflicts and maintaining a strong partnership that continues to develop. Assuming there is no absolute alliance in the history of international relations, what potential crisis moments could arise for the Republic of Korea (ROK)-US alliance in the future? Based on this research question, this study aims to identify unprecedented conflicts that may threaten the alliance and risks of alliance termination by employing a literature review. The results indicate that the most likely crisis for the ROK-US alliance would arise if the nuclear umbrella commitment is nullified. Although the nuclear umbrella commitment has been specified through various mechanisms, such as the Extended Deterrence Strategy and Consultation Group (EDSCG) and the ROK-US Nuclear Consultative Group (NCG), questions remain about its reliability. Specifically, while the US has historically held a “justifiable” obligation to provide it with a nuclear umbrella, South Korea’s conventional capabilities against North Korea have reached the level of “sufficiency.” Therefore, the nullification of the nuclear umbrella commitment is likely to bring about an ROK-US alliance crisis.