This problem is not exclusive to the U.S.-ROK alliance. The recent Sino-Japanese standoff over the Senkaku/Diaoyu Islands has also raised the question of how extended deterrence functions at lower levels of escalation. It remains highly unlikely that the United States will ever have to decide whether or not to use nuclear weapons on South Korea’s behalf. China’s rise and North Korea’s continued nuclear and missile developments make it quite probable, however, that lower-level incidents will continue to surface, provoking anxieties from allies who feel that the U.S. umbrella is not water-tight. The return of tactical weapons may make some South Koreans feel that American nuclear use on their behalf is modestly more likely, but it will not solve the puzzle of how to shore up deterrence at lower levels of conflict.
South Korean calls for the return of NSNWs should not be dismissed, but taken as a signal that further assurance from the United States is needed. Whether through the recently established U.S.-ROK Extended Deterrence Policy Committee or other channels, the alliance must make coordination around lower-level threats a top priority. A failure to do so could result in serious alliance divisions when crises do arise, and only exacerbate feelings of insecurity in Seoul. Extended deterrence doubts could also have regional reverberations if they result in a more robust South Korean nuclear program.
There are, however, several reasons for optimism: The U.S.-ROK alliance will soon celebrate its 60th anniversary, and has weathered many a storm since its founding. The alliance has maintained cohesion despite several recent challenges, including three DPRK nuclear tests, numerous missile launches, the sinking of the Cheonan, and shelling of Yeonpyeong. At 95 percent, South Korean popular support for the pact could scarcely be higher. In light of these facts, the United States and ROK should commit to finding new and innovative defense and deterrence solutions to deal with lower-level conflict. The redeployment of tactical nuclear weapons to the Korean Peninsula is a Cold War solution to a 21st century problem.Enjoying this article? Click here to subscribe for full access. Just $5 a month.
Mira Rapp-Hooper is a doctoral candidate in political science at Columbia University where she is completing a dissertation on extended deterrence and alliance politics