Are China’s THAAD Fears Justified?

By Sukjoon Yoon

February 20, 2015

There is speculation that the U.S. will deploy its THAAD batteries to South Korea. Should China be worried? 

The U.S. has been giving out ambiguous signals on whether it intends to deploy Terminal High Altitude Area Defense (THAAD) batteries to South Korea. For its part, China has repeatedly expressed serious concerns and deep unhappiness about the prospect. From a South Korean perspective, this is regarded as a political rather than a military matter. Would China’s strategic security really be compromised by such a deployment?

On February 4, Chinese Defense Minister Chang Wanquan delivered China’s first official response to ongoing speculation about the prospective deployment of the U.S.-developed THAAD to South Korea, during the bilateral “cooperative” defense ministers meeting. General Han Min-koo, his South Korean counterpart, attempted to allay Chinese concerns by reiterating that there has been no agreement between South Korea and the U.S. on this issue. Nevertheless, Beijing is exerting heavy pressure on Seoul to speak out against any such deployment, claiming that it would endanger their bilateral relationship and threaten regional peace and stability. Why is China so sensitive?

China’s Concerns

Whenever a state places defensive weapons and systems at forward bases to protect forward forces from a specific adversary, this can easily give rise to political misunderstandings by neighboring states, resulting in unintended military escalation. For China, the deployment of THAAD to South Korea is just such an apparent provocation.

The deployment would imply that South Korea is part of the Ballistic Missile Defense (BMD) led by the U.S. Missile Defense Agency. South Korea is also developing an indigenous missile defense system against North Korean threats, the Korea Air Missile Defense (KAMD) system, which is less likely to antagonize China than THAAD, since it will not be integrated into the wider BMD system designed to counter Iran in Europe and China in the Asia-Pacific.

Moreover, operating THAAD in South Korea represents an explicit threat to China’s asymmetric Anti-Access/Area Denial (A2/AD) strategy, which aims to exclude forwarded U.S. forces from the so-called first island chain. So China could interpret THAAD deployment by South Korea as a major military posture by the U.S. intended to neutralize China’s A2/AD strategy. In September 2013, Jane’s Defence Weekly reported a successful test of an integrated linkage between the Aegis and THAAD systems, the fourth consecutive successful intercept test. THAAD can therefore serve as a hard kill tool for the broader GBMD system. China is also understandably concerned about South Korean involvement in the trinational intelligence sharing accord signed last year with Japan and the U.S. and the extent to which this facilitates GBMD coordination.

Moreover, THAAD’s range will extend beyond the Korean Peninsula. The coverage provided by the existing sea-based Aegis system will be greatly extended by the planned deployment of AN/TRY-2 radars. These track inbound short- and medium-range ballistic missiles (SRBMs and MRBMs) with a high-resolution X-band (8-12.4 GHz) phased-array sensor system providing a 120-degree azimuth field out to 1,000∼3,000km, effectively covering the whole of mainland China.

China’s Fears Justified?

China is clearly rattled by the possible consequences of the U.S. plans to deploy additional defensive THAAD to the Asia-Pacific region. Jane’s Defence Weekly reported in April 2013 that the first THAAD was installed in Guam that month; it is intended to provide early intercept capability for North Korean missiles during their boost or ascent phase.

Military leaders in Beijing will have noted General Curtis Scaparrotti’s infamous remarks during his keynote speech at a defense-related forum held in Seoul on June 3, 2014. Scaparrotti recommended the deployment of THAAD to South Korea as a superior option to KAMD, citing THAAD’s capability to engage all classes of ballistic missiles and in all phases of their trajectories. This rings alarm bells for China, which sees the U.S. stance as intended to deter not only North Korean WMD threats, but also as a military rebalancing to Asia in which the U.S. acquires the capacity to detect air and missile trajectories over China.

What has particularly disturbed the Chinese military is the prospect of the U.S. linking individual sensors, interceptors, and communications assets dispersed all around the Asia-Pacific region into a comprehensive and integrated BMD system to interdict Chinese ballistic missiles in the boost and ascent phases of their trajectories. This would allow THAAD to penetrate and severely compromise China’s air defense zone. The Chinese senior political and military leadership, right up to President Xi Jinping, are worried that the deployment of THAAD and Aegis surface combatants in and around Japan and South Korea will prove a game changer. This is because China has numerous SRBMs and MRBMs which, in the event of conflict, could potentially annihilate U.S. forward bases; but which could be neutralized with a full deployment of THAAD and related systems.

No Game Changer

The South Korean press has exaggerated the significance of this issue, at least insofar as it concerns South Korea directly. If THAAD is indeed deployed in South Korea, then it will be the U.S. using this system to protect its forward military forces in South Korea, which are under constant threat from North Korea. Therefore, if the Chinese are concerned, Beijing should take the matter up directly with Washington, instead of leaning on Seoul and thereby fuelling the ongoing speculation about the possible deployment of THAAD.

And China should remember that South Korea is a core strategic partner, and that their bilateral relations have been growing ever closer and more consolidated, while China’s ties with North Korea have deteriorated. It must be evident that South Korea has no interest in deliberately provoking China. The controversy about whether to deploy THAAD is not being taken lightly in South Korea: we understand the Chinese standpoint.

All things considered, China should accept at face value the U.S. insistence that the purpose of deploying THAAD in South Korea is to protect the U.S. military force in South Korea from incoming North Korean SRBMs and MRBMs. China should also recognize that South Korea has no intention to be integrated, in the way that Japan is, into the U.S.-led theater BMD architecture which counters Chinese SRBMs and MRBMs targeting U.S. forward-deployed military forces in the region. Given China’s vast stockpile of ballistic missiles, which underpin its A2/AD capabilities, it is not surprising that the U.S. is incrementally building a collective BMD system in East Asia. With continuing technological advances, Chinese ballistic missiles are becoming ever more capable and sophisticated, so that with the possible deployment of THAAD to South Korea, and even with the ultimate regional integration of THAAD and related systems, the Chinese will still be able to retain a very adequate defensive posture.

South Korea represents a significant strategic wedge, balanced between China’s declared vision of a New Asian Security and the U.S. implementation of its rebalancing to Asia. It is true that South Korea hosts U.S. forward military forces on the Korean Peninsula, but these number fewer than 30,000. Again, China should take up the issue of THAAD deployment in South Korea directly with the U.S., through the recently established bilateral military-to-military channels. It should refrain from pressing South Korea to directly oppose the U.S.: Chinese interests are better served by allowing South Korea strategic autonomy, while China continues to hedge its bets between the two Koreas.

Sukjoon Yoon is a retired navy captain and a senior research fellow of the Korea Institute for Maritime Strategy. He is also a visiting professor at the Department of Defense System Engineering, Sejong University, Seoul, Korea.