Table of Contents

Given the precarious state of U.S.-China relations and the lack of basic trust between the two sides, deep, far-reaching cooperative measures to resolve this long-standing dispute over missile defense likely are not realistic. Even simple, reciprocal transparency measures on missile defense capabilities and policy plans appear to be a challenging prospect under current conditions. Meanwhile, it does not appear plausible that the United States and China could undertake more ambitious confidence-building measures, such as establishing joint missile defense data fusion centers, as some have proposed.1 Arms control measures, such as limits on the number or capabilities of missile defense interceptors or radars, as China and Russia have advocated, appear even less realistic.

What, then, can be done? Even if the two countries cannot fully avoid the larger security dilemma, completely end strategic competition, or wholly settle basic questions about future strategic intentions, they can still take steps to ameliorate this apparent impasse. The first step toward cooperation is to acknowledge and thoroughly study the manifold ambiguities surrounding the missile defense dispute. Mitigating these ambiguities will not be easy, and the task will become even more difficult in the future if the bilateral strategic rivalry continues to grow. That said, precisely because a new Cold War is becoming an ever more realistic prospect, redressing the ambiguities that underlie this dispute could prevent it from further fueling hostility and perhaps even help put the strategic relationship on more stable footing.

Even if China and the United States cannot fully avoid the larger security dilemma, completely end strategic competition, or wholly settle basic questions about future strategic intentions, they can still take steps to ameliorate this apparent impasse.

By the same token, it is possible that, after serious and sincere efforts to address this issue, U.S. and Chinese officials and analysts may conclude that the ambiguities may not be fully resolvable. But if the two sides can at least agree that some ambiguities are hard to resolve due to technical or geographical realities, this can still help build better mutual understanding and mitigate worst-case thinking about each other’s strategic intentions. The steps outlined below are designed to move the two countries in this more modest and realistic direction.

What China Can Do

To begin with, China must dispel ambiguities about its misgivings on U.S. missile defense. Before the United States and its allies can address China’s concerns over missile defense, Beijing needs to clarify what precisely it is concerned about. Is China primarily alarmed about its nuclear deterrent or is it equally worried about its conventional deterrent and attack capabilities, which are critical to defending its perceived core interests in possible regional conflicts? In the case of nuclear deterrence, does China worry mostly about its ability to conduct all-out nuclear retaliation, as most experts have focused on, or about scenarios involving more limited nuclear use? Does China believe its nuclear deterrent is mostly affected by U.S. strategic (intercontinental) or regional missile defense systems? China needs to have clear answers to these questions for its misgivings to be understood.

China also needs a clear, consistent standard for gauging the sufficiency of its nuclear deterrent. To put things simply, China has to define how many warheads it believes it must deliver to the U.S. homeland to achieve strategic nuclear deterrence and how many warheads it must deliver to regional targets to deter a regional nuclear conflict. China would not need to reveal exact numbers externally; rather, a clear definition would provide a consistent standard against which Chinese strategists could plan nuclear modernization efforts.

China also needs a clear, consistent standard for gauging the sufficiency of its nuclear deterrent.

Relatedly, China needs a clear way of evaluating the impact of a possible U.S. first strike coupled with missile defense capabilities. Current public discussions about the effects of a U.S. first strike on China’s nuclear forces are superficial and abstract.2 These conversations suggest that China has neither developed nor systematically implemented a suitable methodology. Chinese experts disagree over such fundamental issues as whether advances in U.S. surveillance and reconnaissance capabilities over recent decades have meaningfully enhanced the United States’ ability to track and threaten Chinese mobile missiles.3 These disagreements may reflect a lack of rigorous research by experts, which prevents concrete, detailed internal discussions about sizing China’s nuclear arsenal.

In a similar vein, China should develop clear criteria on how effectively missile defense must perform to pose a realistic threat to its deterrent. In some U.S. research on the potential impact of U.S. missile defense on near-peers’ nuclear forces, it was assumed that missile defense would pose a realistic threat if it can “block 20 percent or more of an opponent’s ballistic-missile retaliation on generated alert.”4 Clear criteria, even if undisclosed, help to avoid exaggerated threat perceptions. For the same purpose, it is no less important to ensure that technical evaluations of the effectiveness of U.S. missile defense systems go through rigorous peer review. Such oversight can help identify and correct misunderstandings about key technical capabilities of U.S. missile defense programs, which are not rare in the existing literature. More open discussions and public debates on the efficacy of U.S. systems do not risk divulging sensitive Chinese military information and can be very helpful for developing balanced understandings on key technical issues that can inform both internal policy deliberations and dialogues with the United States.

Furthermore, China needs to be more transparent about how its nuclear modernization efforts are proportionate to the objective threat posed by missile defense. If China has a clear definition for the sufficiency of its nuclear deterrent and a clear methodology for evaluating the effects of a U.S. first strike and missile defense, it should then be able to scale its nuclear modernization program accordingly. Transparency about the assumptions underlying this program would help assuage foreign concerns that China’s nuclear modernization is driven by a more expansionist, aggressive agenda than the modest goal of preserving deterrence. At bilateral and multilateral dialogues, for instance, China’s efforts to promote the image of a transparent and restrained nuclear power can focus more on explaining these underlying assumptions and calculations so as to help the international community better examine the connection between foreign powers’ missile defense and Chinese nuclear modernization. If China can assure other countries of its peaceful intent, it would have a greater chance of gathering international support for constraining the development of missile defense.

Top Chinese decisionmakers can help check the influence of domestic parochial interests and limit group-think by highlighting the importance of a proportionate response to missile defense and by having the political will to implement that vision. As China has invested even more in its military and defense industry over the past several decades, parochial bureaucratic interests are becoming more important in determining policy outcomes, and various domestic stakeholders have a growing interest in overestimating external threats. Chinese scholars, unlike their foreign counterparts, have not paid much attention to how a state’s military-industrial complex can influence defense policy and military procurement decisions in ways that ultimately undermine the state’s security. As a result, few Chinese security analysts are raising potential concerns about the prevalence of worst-case thinking on such issues. The Chinese security community needs to change this by having transparent internal discussions on the issues identified above.

Additionally, China should clarify the role of its theater nuclear missiles. Chinese strategists must have considered more sophisticated options than all-out nuclear retaliation in response to any rival nuclear attack. Without knowing what role theater nuclear forces play in such options—and how Beijing understands external threats to those forces—it is impossible for China and the United States and its regional allies to have a meaningful discussion about how theater missile defense systems could affect Beijing’s nuclear deterrent and whether measures can be taken to mitigate their impact.

China’s future defense white papers can consider shedding more light on this issue. In this respect, the 2018 U.S. NPR report could be something of a general model (although China does not necessarily agree with the U.S. observation and evidence in this particular case): the NPR report clearly explained why the U.S. government is concerned that its theater nuclear forces are inadequate given its beliefs that Russia might use nuclear weapons in a limited way early in a conflict and that Moscow is developing new types of tactical weapons to support this doctrine. By extension, China’s clarification could also help other countries better evaluate the credibility of its NFU policy, reduce their concerns about the nuclear threat Beijing poses (which, in turn, may reduce investments in missile defense), and mitigate the risks of inadvertent escalation in a crisis.

What the United States Can Do

Mitigate U.S.-China differences on countering North Korean nuclear weapons. U.S. concerns about North Korea’s nuclear and missile programs remain key drivers of the development and deployment of U.S. strategic missile defense systems designed to thwart enemy missiles launched from East Asia. But U.S. decisionmakers should be aware that the ambiguity over whether U.S. strategic missile defense capabilities are aimed at North Korea or China itself contributes significantly to Beijing’s worst-case assumptions about U.S. intent. Moreover, ongoing improvements to North Korea’s nuclear and missile capabilities will likely drive the United States to augment its strategic missile defense systems, further intensifying the security trilemma between Beijing, Pyongyang, and Washington.5

At the operational level, the United States may feel it needs a high degree of confidence that even if North Korea launched every one of its ICBMs in a surprise attack, U.S. missile defense systems could intercept all of them. But U.S. policymakers should recall that Chinese strategists worry that such U.S. missile defense systems could neutralize China’s surviving nuclear weapons after a U.S. first strike, a concern heightened by China’s geographic proximity to North Korea.

Despite hopes that the United States and China would find a way to cooperate more to try to convince North Korea to denuclearize, Chinese and U.S. geostrategic interests are increasingly diverging amid their heightened strategic rivalry, making such coordination more difficult to achieve. As a first step to mitigate such challenges, the United States and China should jointly evaluate North Korea’s nuclear and missiles capabilities and the potential threats they pose to other countries and regional stability, so as to narrow or at least shed light on the gap between Chinese experts’ generally more sanguine and U.S. experts’ typically more pessimistic assessments.6 U.S. allies, such as South Korea, can help convene and moderate such joint evaluations, giving China a stronger incentive to participate.

A U.S. NFU commitment could help. The United States could help mitigate this dilemma by adopting an NFU policy toward China, or, less formally, by forging a private understanding with China on NFU. This would effectively address China’s fear of a U.S. first strike, thus substantially reducing the potential impact of U.S. missile defense on China’s nuclear deterrent and making it much easier for Washington to assure Beijing that U.S. missile defense systems cannot undermine its nuclear deterrent. China’s own NFU policy and its long-standing call for other nuclear powers to adopt such a policy means that even a U.S. declaratory policy of NFU would help address Chinese concerns about the risks of a preemptive U.S. nuclear strike. Despite the long internal debate within the United States about NFU, the potentially huge benefit of bringing Beijing and Washington closer to resolving their missile defense dispute should give one important reason for the United States to seriously consider adopting this policy toward China.

The United States could help mitigate this dilemma by adopting an NFU policy toward China, or, less formally, by forging a private understanding with China on NFU.

Examine the technical feasibility of distinguishing certain missile defense systems. While a U.S. NFU declaration toward China would be valuable, it would not solve every type of ambiguity. For example, the ambiguity over whether U.S. theater missile defense capabilities could contribute to strategic defense would persist. Differentiating theater and strategic missile defense systems is already difficult, and technological trends—such as the development and networking of more advanced sensors—are making this task even more burdensome. But serious efforts aimed at mitigating these challenges can still be helpful, including (for example) studies to understand the technical and operational feasibility of drawing distinctions between theater and strategic systems. The United States can consider inviting Chinese experts to participate in such studies at the unclassified level. Even a joint understanding and acknowledgment of the technical ambiguities and especially the challenges of addressing them might somewhat help mitigate worst-case thinking. Similarly, the United States should conduct studies to examine the technical and operational feasibility of constructing an effective strategic missile defense system against North Korean ICBMs without undermining Chinese second-strike capabilities. U.S. experts should find ways to engage Chinese counterparts in this process, as such collaboration can demonstrate U.S. willingness to address Chinese concerns and be a good confidence-building measure in itself.

What Both Sides Can Do Together

Contain any broader security spillover effects. The most urgent task for both countries is to keep their dispute over missile defense from spilling over into other military domains or fueling a broader strategic and military competition. U.S. missile defense systems motivate China to consider a system penetration strategy; build up its nuclear forces; and develop alternative means of delivery, such as hypersonic vehicles, strategic bombers, air-launched ballistic missiles, and SLBMs.7 If China does implement the system penetration strategy, that would further push Washington and Beijing into a comprehensive military competition.

The most urgent task for both countries is to keep their dispute over missile defense from spilling over into other military domains or fueling a broader strategic and military competition.

Deepen dialogues and exchanges between experts. To keep the tail from wagging the dog, so to speak, both countries’ expert communities need to develop much more in-depth, nuanced understandings of each other’s internal policy deliberations. Chinese experts who are aware of the diversity and complexity of relevant U.S. domestic debates and of how U.S. domestic politics can sometimes be a greater driver of U.S. missile defense policymaking than calculations of long-term security interests tend to be more sympathetic than their peers to the idea that the U.S.-China missile defense dispute is a security dilemma. Such experts appear less likely than others to believe that U.S. policies on missile defense aim at undermining Beijing’s nuclear deterrent or other key security interests.8 Consequently, it may be useful for both countries’ experts to strive to describe and explain, in an unclassified manner, their respective domestic debates about nuclear and missile defense policy. This approach could help develop nuanced understandings about each other’s policy, reduce misunderstandings caused by lingering ambiguities, and gradually cultivate greater sensitivity to the security dilemma at hand.

Ambiguities about intentions are sometimes caused by genuine disagreements over technical issues. In the case of the THAAD dispute, for example, technical experts from the two countries have genuinely divergent views about the technical capabilities of the THAAD system, especially the AN/TPY-2 radar. Yet, unfortunately, they have failed to jointly explore the origins of their disagreements or seek out a common understanding. As a result, Chinese officials believe the United States deployed this system to South Korea to undermine China’s strategic security interests and that Washington simply pretends that the system does not harm China. U.S. officials, by contrast, believe that China knows full well that the system does not pose a serious threat to it and that Beijing’s arguments to the contrary are intended to help it achieve other geopolitical goals, such as driving a wedge between the United States and its South Korean ally.9

This experience shows that the two countries’ technical experts need to engage each other in substantive, in-depth dialogues, exchanges, and joint research. Such joint research and exchanges based on open-source information can, without disclosing classified information, help narrow perception gaps. Due to the highly technical nature of missile defense, Chinese technical experts wield unusually important influence in shaping the views of the country’s top political leaders and decisionmakers on such issues. Such in-depth exchanges, therefore, can be particularly helpful for informing, guiding, and navigating relevant national and bilateral policy debates constructively. That said, such efforts are most effective if they occur early in a potential policy dispute. After political leaders have already formed their views, it becomes more difficult to reshape them based on technical analysis.

Remember the lessons of Cold War engagement. Beijing and Washington must demonstrate sufficient political will to establish and sustain technical and operational exchanges. U.S. decisionmakers are frustrated that Chinese interlocutors sometimes seem to prefer complaining about malign U.S. intentions instead of engaging in substantive dialogues to help clarify matters. They feel their long-term efforts to engage Russia on missile defense have been futile and their repeated efforts to talk to China have been met with closed door after closed door. For China, seemingly unsuccessful U.S.-Russian engagement reinforces suspicions that if a nuclear power as strong as Russia could not make the United States seriously address its concerns, Beijing may have little hope of convincing Washington to limit its missile defense programs to accommodate Chinese interests.

Yet these historical lessons are not completely correct. During U.S.-Russian engagement, Washington did make important changes to its missile defense plans, partly to address Russian concerns. Examples include the Obama administration’s decision to abandon plans to build a third GBI deployment site in Poland and to cancel the fourth phase of the EPAA by not developing advanced SM-3 IIB interceptors.

Chinese leaders should draw confidence from this history: engagement with the United States can produce meaningful results, and Beijing does have a chance to influence U.S. missile defense policy through substantive talks. But China’s lack of experience in holding official bilateral talks on missile defense and its self-perceived sense of inferiority about its capabilities in this highly technical domain may add to its hesitation. For U.S. decisionmakers, it is necessary to help address Beijing’s lack of confidence by being more willing to respond to Chinese policy concerns. Unlike the nuclear parity between Washington and Moscow, the asymmetric nuclear relationship between Washington and Beijing means that it may make sense for Washington to drop strict requirements on equality or reciprocity with Beijing when it comes to information sharing, transparency, and other mutual commitments during visits and dialogues, at least initially.

Keep security concerns from becoming a self-fulfilling prophecy. Chinese and U.S. political leaders and policy experts need to be particularly vigilant that ambiguous evidence does not lead to self-reinforcing interpretations of the other side’s intent. This danger is especially pernicious because some Chinese and U.S. experts have fallen prey to circular logic on such questions. For example, since 2007, many Chinese policy experts have argued that—because official U.S. documents, including the Defense Department’s Quadrennial Defense Reviews, have characterized China as having “the greatest potential to compete militarily with the United States”—China is justified in interpreting U.S. military capabilities, including missile defense systems, as intended to “contain” China.10 At the same time, Chinese policy experts often argue that the perceived threat from U.S. missile defenses is evidence of broader U.S. strategic hostility toward China.11 Such circular reasoning is also observable in the United States. Some U.S. experts, for example, argue that China’s nuclear modernization will lead it to adopt a more aggressive nuclear posture and become more geopolitically ambitious.12 Others argue that China’s more aggressive strategic objectives drive Chinese nuclear modernization.13 Accepting both arguments as correct could reinforce existing pessimistic interpretations of China’s intent.

This set of recommendations seeks to move U.S.-China discussions on missile defense beyond superficial talking points and address ambiguities involving U.S. and Chinese capabilities and policies. China and the United States can pursue some of these efforts unilaterally, and the others can be discussed, explored, and promoted jointly at track 1.5 or even track 1 dialogues. But all of them need to be built on a deeper understanding of the impact of ambiguities in the U.S.-China dispute over missile defense.

Efforts along these lines are necessary to contain further escalation of this dispute and prevent it from continuing to destabilize the bilateral security relationship and disrupt the security order in the Asia-Pacific. At a time when concerns that the United States could potentially deny China a credible nuclear deterrent are already driving an unprecedented domestic debate in China about whether it needs to massively build up its nuclear forces,14 the two countries urgently need to ensure that their missile defense dispute does not further fuel a disastrous nuclear arms race and a full-blown military rivalry.


1 Private conversations with international experts, August-September 2019.

2 Professor Wu Riqiang has made a recent effort to tackle such issues. See, for example: Wu Riqiang (吴日强), “Living With Uncertainty: Modeling China's Nuclear Survivability,” International Security 44, no. 4 (2020) 84–118.

3 Private conversations with Chinese experts in Beijing, 2019.

4 Wilkening, Ballistic-Missile Defence and Strategic Stability.

5 A trilemma arises when one state’s efforts to defend itself against a second inadvertently spark security concerns in a third country. See Linton Brooks and Mira Rapp-Hooper, “Extended Deterrence, Assurance, and Reassurance in the Pacific During the Second Nuclear Age,” Strategic Asia 2013–14: Asia in the Second Nuclear Age (Washington, DC: National Bureau of Asian Research, 2013), 292–293.

6 Wu, “China’s Anxiety About US Missile Defence: A Solution”; and Roberts and Wu, “Letters to the Editor.”

7 The nuclear role of China’s future long-range hypersonic vehicles and its next-generation strategic bombers is speculated about and has not been confirmed.

8 Shi Yinhong (时殷弘), “美国国家导弹防御计划与中国的对策” [U.S. national missile defense plan and China’s response], Pacific Journal (太平洋学报) no. 4 (2000): 39–44.

9 Tong Zhao, “The Perception Gap in the THAAD Dispute—Causes and Solutions.”

10 U.S. Department of Defense, Quadrennial Defense Review Report, (Washington, DC: U.S. Department of Defense, February 6, 2006); and He Xingqiang (何兴强), “美日搭建导弹防御系统剑指何方” [What are U.S. and Japan aiming at with their deployment of missile defense], China National Defense News (中国国防报), July 10, 2007, 2.

11 Wang Xiaohu (王晓虎), “美国楔子战略与亚太联盟预阻” [U.S. wedge strategy and prevention of alliances in the Asia-Pacific], Global Review (国际展望) no. 3 (2017): 58–77.

12 Thomas J. Christensen, “The Meaning of the Nuclear Evolution: China’s Strategic Modernization and US-China Security Relations,” Journal of Strategic Studies 35, no. 4 (2012): 447–487.

13 Schneider, “Nuclear Weapons in Chinese Military Strategy.”

14 Hu, “China Needs to Increase Its Nuclear Warheads to 1,000.”