A U.S.deployment of a THAAD system in South Korea would prove that its anti-missile system is at least partly aimed at offsetting China’s deterrent capabilities.A THAAD platform will do little to improve South Korea’s military deterrence with North Korea;rather it will mean it will push China to take countermeasures,ushering in a new arms race in Northeast Asia and posing a severe test to regional security. A USdeployment of a THAAD system in South Korea would prove that its anti-missile system is at least partly aimed at offsetting China’s deterrent capabilities. A THAAD platform will do little to improve South Korea’s military deterrence with North Korea; rather it will mean it will push China to take countermeasures, ushering in a new arms race in Northeast Asia and posing a severe test to regional security.