The Buzz

THAAD and Thucydides: Seeing the Forest Beyond the Trees

Since the July 7 announcement by the U.S.-Korea alliance to deploy the Terminal High-Altitude Area Defense (THAAD) system on the Korean peninsula, analysts and commentators have been discussing whether and how Beijing would retaliate against Seoul and whether the decision would lead to a dangerous arms race between the United States and China. These are important questions, but Thucydides might say that they are also missing the forest for the trees. By itself, the THAAD controversy is not a make-or-break issue in China-South Korea relations or in the U.S.-China arms race dynamics but is simply one symptom of broader trends, namely the growing U.S.-China competition in Asia and the evolution in strategic military technologies.

To begin with, there is the underlying geopolitical context. The THAAD decision would not be so controversial, if not for the current state of U.S.-China relations defined by increasing tensions and deepening mistrust. Deploying THAAD in South Korea would not jeopardize the effectiveness of China’s nuclear deterrent since the system is meant to intercept short to intermediate-range ballistic missiles during their terminal phase, but not during their boost or mid-course phase. THAAD in South Korea cannot block Chinese missiles traveling toward the United States. Moreover, Washington and Seoul have repeatedly assured a paranoid Beijing that they plan to use THAAD in “terminal mode” to deter and defend against Pyongyang’s missile capabilities, instead of using the system in “look mode” to scan deep into Chinese territories.

Yet, it is clear that Chinese political analysts view the THAAD issue through the lens of broader geopolitics, particularly in the context of the U.S. rebalance to Asia. Chinese commentaries often argue that the United States is using THAAD to “drive a wedge” between China and South Korea in order to bring a reluctant Seoul into a U.S.-Japan-South Korea coalition to contain China. This suspicion is bolstered by the fact that many Chinese observers see THAAD as having questionable utility in countering North Korean threats to the Seoul metropolitan area, which is home to approximately half of South Korea’s population and is mere twenty to thirty miles from the demilitarized zone. In any case, the planned deployment of THAAD will not cover Seoul. Many in the United States, too, are treating this issue in geopolitical terms, arguing that China is opposing the deployment of THAAD to “wedge itself between South Korea and the United States” or to “establish a precedent for its ability to influence the security decisions of its neighboring countries.”