China publicly professes a foreign policy of non-interference, and Beijing's comments have led to an unequivocally negative response from Seoul, which sees them as tantamount to bullying. Beijing has indeed used its regional economic heft in the past to subtly remind its neighbors to maintain friendly ties with China and avoid actions — such as cooperating in U.S. defense architecture — that undermine those relations. China has even exploited South Korea's fragmented political field to stir up controversy in Seoul over defense relations with Washington. Beijing has also played on South Korea's traditional distrust of Japan to keep the U.S.-South Korea-Japan defense triangle in Northeast Asia off-balance. All of China's pressure, however, has been applied in a less overt and confrontational manner than its recent pressure over THAAD. Given the nature of its comments and the predictable reaction, Beijing's public stance may reflect a much deeper concern.
However, the issue for China is less about THAAD in particular than about what Beijing sees as the steady encroachment of U.S. missile defense architecture in the Asia-Pacific and in particular on mainland Asia. Although in the post-Cold War world there is little public consideration of nuclear balance, strategic security is still a critical component of national security. With China facing three potential nuclear competitors — Russia, India and the United States — maintaining a robust and viable nuclear deterrent is critical. China is a nuclear power, but one with a poorly developed nuclear triad. It relies primarily on its road-mobile ballistic missiles and its nascent ballistic missile submarine fleet. China's capabilities mean it must always ensure that it retains a second-strike capability to deter any first strikes against itself from an opponent. In addition, a viable nuclear deterrent may also affect the calculus of conventional intervention by the United States in times of military crises in Asia.
Cold War Resonances
Anti-ballistic missile defense was a key source of tension between the United States and the Soviet Union during the Cold War for precisely the same reason. The U.S. and Soviet fear was that if an effective anti-ballistic missile defense system were developed, the opponent's nuclear forces would be effectively neutralized. Once neutralized, the potential aggressor would be free to force political concessions or even carry out military action without fear of nuclear escalation. Beijing has been shaping its Pacific posture — particularly in the East and South China seas — to raise the cost of U.S. intervention. Raising the cost of intervention would shape the political — and thus security and economic — balance in the region in favor of China. If China can make the cost of intervention higher than the reward, it does not need to engage in military activity to gain regional political concessions. And the nuclear component remains a very real element of this defense posture.
The United States and Soviet Union avoided direct conventional conflict throughout the Cold War. India and Pakistan have had border spats, but no major conflict. The United States hardly hesitated to engage in military activity in Afghanistan and elsewhere in the Middle East, but it has avoided engagement in North Korea. It also did not directly involve itself in the conflicts inside Georgia or Ukraine against Russian and Russian-backed forces. At its most basic level, the Cold War model holds. The concept remains that the possession of viable nuclear forces compels any potential opponent to recalculate the risk level of direct engagement. Even as the post-Cold War world evolves toward an apolar power configuration, nuclear force is still an important component of strategic thinking.
In one sense, a U.S. move to counter, degrade or otherwise undermine Chinese nuclear capability through regional anti-ballistic missile systems is a way for the United States to expand its military options in relation to China by taking its first step toward further expansion of regional anti-ballistic missile systems. China's public protest against the deployment of a THAAD-affiliated radar system in South Korea that would reach into China is about the further expansion of U.S. anti-ballistic missile capabilities aimed at China. It is about a perceived U.S. move toward a real military containment of China and the erosion of China's nuclear deterrent. It also about the possibility — even if small and distant — of real conflict between China and the United States at a time and place chosen by Washington, not Beijing.
Editor's Note: This is the second of two analyses on THAAD deployment in South Korea, read the first part here.