Taiwan is currently the single biggest point of contention in U.S.-China relations, and U.S. allies have a crucial role to play in efforts to prevent a great-power war over the island. South Korea, however, has remained relatively ambiguous about its willingness to support U.S. efforts to push back against China’s growing influence in the region, including in the Taiwan Strait. As the Yoon administration is now creating an opening for a more proactive approach, what can South Korea do in a Taiwan contingency?

A new article in The Washington Quarterly provides a framework for analyzing South Korea’s potential role in this era of strategic competition through the lens of war over Taiwan. The authors — Oriana Skylar Mastro, a Center Fellow at APARC, and Sungmin Cho, a professor at the Daniel K. Inouye Asia-Pacific Center for Security Studies — build upon traditional concepts of balancing to create a nuanced, operationally relevant strategy for South Korea to contribute to the defense of Taiwan.

They explain South Korea’s approach to the Taiwan issue to date; evaluate South Korea’s strategic importance and what it can do to support U.S.-led efforts to compete with China; explore how China and North Korea may respond to increased South Korean cooperation with the United States, along with the potential obstacles this cooperation could create; and recommend ways to leverage the US-ROK alliance to enhance deterrence against China with respect to Taiwan.

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Mastro and Cho recognize that it is operationally and politically infeasible for South Korea to fight side-by-side with U.S. forces against China in a Taiwan scenario or to build its military sufficiently to deter Chinese aggression against Taipei. South Korean strategists must also consider the costs of China’s and North Korea’s potential responses to greater South Korean involvement in defending Taiwan. Still, Seoul can play a significant role in deterring Chinese aggression.

According to Mastro and Cho, South Korea’s optimal strategy to navigate the U.S.-China rivalry should meet two conditions. First, it should contribute to the vision of a free and open Indo-Pacific, including deterring Chinese aggression against Taiwan. Second, it should be able to make China hesitate to take punitive actions against South Korea. Thus, South Korea can provide rear-area support to the United States, such as intelligence gathering, ammunition supplies, or noncombatant evacuation. It can also support the strategic flexibility of US Forces Korea (USFK) and be more proactive in deterring North Korean aggression and provocation to free up U.S. resources to focus on China in a contingency scenario.

Moreover, South Korea could contribute toward forms of “collective resilience” against China’s economic statecraft, such as collective economic sanctions, and leverage its position as one of the world’s leading producers of advanced semiconductors to complicate China’s calculus. Finally, Seoul’s diplomatic support of U.S.-led efforts to defend Taiwan can influence Beijing to take seriously the international community’s potential united response against any attempt to invade Taiwan.

“Given the heightened urgency over tensions in the Taiwan Strait, Washington and Seoul should pursue these options immediately to maintain peace and stability in the region before it is too late,” the authors conclude.