Managing the Impact of Missile Defense on U.S.-China Strategic Stability

China has long been concerned that the United States could launch a comprehensive nuclear first strike on China and then use its missile defenses to intercept the surviving Chinese nuclear missiles. In the 1960s, the United States justified its deployment of limited missile defenses against China’s emerging nuclear capabilities.2 The Reagan administration’s Strategic Defense Initiative alarmed Beijing about America’s missile defense ambitions, although the continuing honeymoon between Washington and Beijing helped mitigate Chinese concerns. Nonetheless, the ending of the Cold War, the continued turmoil in the bilateral relationship, the U.S. withdrawal from the Anti-Ballistic Missile Treaty in 2002, and growing Chinese concerns about the U.S. pursuit of “unilateralism” and “absolute security” have all contributed to greater Chinese anxiety about U.S. missile defenses.

Although some Chinese experts understand that current American missile defense capabilities will not seriously threaten the effectiveness of China’s nuclear deterrent, the mainstream view within the Chinese nuclear policy community is that, in the future, the United States could acquire a much more capable missile defense. Many Chinese experts genuinely believe that the United States has a long-standing interest in neutralizing China’s nuclear deterrent and that the reason Washington has not built such a capability is primarily due to economic and technological constraints.3

Public statements by senior American officials on the issue of missile defense have been important in influencing Chinese policy experts’ interpretation of U.S. policy objectives. These public statements are not always consistent with formal U.S. government positions. For instance, former President Donald Trump once declared, seemingly off-the-cuff, that the U.S. military seeks “to ensure that we can detect and destroy any missile launched against the United States—anywhere, anytime, anyplace.”4 This statement does not align with the formal U.S. position, which rejects the notion that Washington seeks to use missile defense to undermine China’s strategic nuclear deterrent: “The United States relies on nuclear deterrence to address the large and more sophisticated Russian and Chinese intercontinental ballistic missile capabilities.”5 However, statements like the one made by President Trump have had an impact on many Chinese policy experts’ understanding of U.S. missile defense policy and are often pointed to as evidence that Washington’s missile defense programs seek to undermine the bilateral strategic stability relationship.6 This raises the need for governments to reduce inconsistencies in official policy declarations.

To address this issue also requires U.S. officials and defense experts to think by standing in China’s shoes. If the United States possessed a small arsenal but faced a much stronger enemy interested in developing damage-limitation capabilities through a wide range of conventional, nuclear, and cyber strike technologies, the United States, too, would probably develop a deep level of paranoia based on worst-case-scenario thinking and view the enemy’s missile defense development as one more tool to help it achieve nuclear primacy.

China has traditionally emphasized the importance of building trust through a top-down process. Chinese experts stress that the United States should first acknowledge the existence of a mutual vulnerability relationship with China as a strategic reassurance to Beijing that Washington would not seek to undermine China’s nuclear deterrent through missile defense or other means.7 The United States has been reluctant to make an explicit commitment to a mutual vulnerability relationship with China, however—not least due to the concerns of some American allies that this might weaken U.S. extended nuclear deterrence and embolden China to commit military aggression. The Obama administration sought to address its allies’ concern by refraining from explicitly referring to mutual vulnerability; at the same time, it promised to maintain a strategic stability relationship with China. This political commitment alone did not fundamentally change China’s overall suspicion about U.S. missile defense and other developments, but it provided a framework under which the two countries could discuss a wide range of military issues, including missile defense. Such a U.S. political commitment was important to China and remains so today. As the overall bilateral relationship becomes increasingly adversarial, such political reassurance from Washington is even more important in clarifying U.S. strategic intentions in the eyes of Beijing.

That said, China’s concern about U.S. missile defense increasingly goes beyond technology per se. China believes the United States has been using missile defense cooperation as a tool to strengthen alliance relationships with its security allies in the Asia Pacific region and to exert U.S. influence in and control of its allies’ foreign and security policies.8 China has long viewed the U.S.-led alliance as its primary security threat in the region and therefore is very displeased about the role missile defense cooperation may be playing in bolstering such alliance relations. Practical measures that either side could take to effectively address this concern are unlikely to emerge in the foreseeable future.

The lack of a clear declaratory policy and detailed explanatory statements about its strategic security policies also make Beijing’s intentions ambiguous. Some American experts doubt that China is genuinely worried about U.S. missile defense.9 They believe China has a clear understanding that the United States has neither the intention nor the capability to threaten China’s nuclear deterrent in this way. Unfortunately, this American perception is inaccurate. The concerns of Chinese experts—including policy and technical experts—may be misplaced, but the experts are convinced of their views. This indicates that the Chinese experts need to better explain their specific concerns and that American experts need to look deeper into Chinese views as a starting point for building mutual understanding.

More important, Washington has grown suspicious that Beijing has been modernizing its nuclear arsenal for reasons that have little to do with U.S. missile defense development. For instance, some American experts suspect that China is building up its nuclear capabilities because Beijing wants to bolster its status as an international power and/or to expand the role of its nuclear weapons beyond its traditional minimum deterrence posture.10 China may face growing pressure to explain how its nuclear buildup—such as the sudden construction of hundreds of new missile silos in its Gansu, Xinjiang, and Inner Mongolia regions, probably for the purpose of deploying intercontinental ballistic missiles (ICBMs)—was a proportionate response to the U.S. effort to gradually improve its missile defense capabilities.11 The silence of China’s government and its state media’s dismissal of many of these reported developments have further contributed to American suspicions.

In summary, China views U.S. missile defense as posing a greater potential threat to China’s nuclear deterrent than other U.S. military capabilities.12 However, China has not established a clear and convincing linkage between the development of American missile defense capabilities and China’s comprehensive nuclear modernization to make the case for Washington to take seriously Chinese concerns about U.S. missile defense.
 

Endnotes

• 2Jeffrey Lewis, “China’s Orbital Bombardment System Is Big, Bad News—But Not a Breakthrough,” Foreign Policy, October 18, 2021.
• 3吴日强 [Wu Riqiang], “中美如何避免核军备竞赛” [How to avoid a China-U.S. nuclear arms race], 当代美国评论 [Contemporary American review] (2) (2017): 39–60.
• 4David Vergun, “Trump Pledges to Protect America from Any Enemy Missile,” U.S. Department of Defense, January 17, 2019.
• 5U.S. Department of Defense, 2019 Missile Defense Review Report (Washington, D.C.: Office of the Secretary of Defense, 2019), vii.
• 6孙涛 [Sun Tao] and 郭彦江 [Guo Yanjiang], “美国下一代反导体系架构解析” [Analysis of U.S. next generation anti-missile system architecture], 军事文摘 [Military digest] (11) (2021): 61–64.
• 7Amber Wang, “China’s Nuclear Threat Only Keeping Up with US Advances, Chinese Experts Say,” South China Morning Post, October 19, 2021.
• 8安雨康 [An Yukang], 论导弹防御对美国亚太军事同盟的影响 [The impact of missile defense on the U.S. military alliances in Asia-Pacific], 国际关系学院 [Institute of International Relations], Beijing, 2018.
• 9Matthew R. Costlow, “The Missile Defense ‘Arms Race’ Myth,” Strategic Studies Quarterly 15 (1) (2021): 3–9.
• 102021 Annual Report to Congress of the U.S.-China Economic and Security Review Commission (Washington, D.C.: U.S. Government Printing Office, 2021).
• 11Matt Korda and Hans Kristensen, “A Closer Look at China’s Missile Silo Construction,” Federation of American Scientists, November 2, 2021.
• 12Tong Zhao, Narrowing the US-China Gap on Missile Defense: How to Forestall a Nuclear Arms Race (Washington, D.C.: Carnegie Endowment for International Peace, 2020).

For Washington to be willing to put its missile defense program on the negotiating table, Beijing may also need to be prepared to make reciprocal concessions on limiting its own nuclear buildup. To this end, an exchange of ideas about the specific missile defense and nuclear restraints each would like to see from the other would be helpful.

Facing ongoing U.S. conventional, cyber, and nuclear capability development in Asia and the deteriorating bilateral relationship that makes China unwilling to engage in arms control or confidence-building diplomacy, Beijing may feel increasingly motivated to deal with the perceived missile defense challenge through unilateral measures. Decades of fast economic growth have given China the option to substantially expand its nuclear forces at a speed and scale that would offset any potential impact of U.S. missile defense improvements. In addition to the new ICBM silos, China has now publicly endorsed a new policy of developing its own nuclear triad—the delivery of nuclear warheads via sea, land, and air systems—despite the country’s traditional criticism of U.S. and Russian nuclear triad capabilities. Comprehensive modernization has been taking place across the board, including silo-based ICBMs, road-mobile ICBMs, nuclear strategic submarines, and nuclear-capable strategic bombers.13 If Beijing is determined to rely on its own nuclear buildup to address security concerns, that would leave little room for cooperative measures to jointly manage the bilateral nuclear relationship, including the issue of missile defense.

In addition to numerical expansion, China appears hopeful that new technologies, such as boost-glider delivery systems, may help keep China ahead of future missile defense threats. Chinese experts are in general agreement that boost-glider systems could add significantly to China’s capacity to penetrate advanced U.S. missile defense systems, although technical experts continue to explore to what extent intercontinental-range boost gliders may be vulnerable to developments in precise tracking and advanced interception technologies.14 China’s evaluation of the penetration capability of boost gliders vis-à-vis expected U.S. missile defense technological advancement will continue to influence Chinese policy deliberation.

Also important is how much China can develop advanced missile boosters and propellant, stealth materials, decoys, and intelligent trajectory maneuvering technologies.15 In some of these areas, China has become unprecedentedly confident, as Chinese scientists and engineers reportedly have made critical breakthroughs that put China in a leading position ahead of the other major powers.16 China has also been developing and training for operational tactics to increase the overall penetrability of its missile attack, such as coordinating the launch time, sequence, location, and attack directions of groups of missiles, including using artificial intelligence to achieve “intelligent coordination.”17 China is constructing “system penetration” capabilities by developing a wide range of technologies—including anti-satellite (ASAT) technologies—to systematically interfere with all components of the U.S. missile defense network.18 Because China believes a comprehensive military competition with the United States is unavoidable and that it therefore has to modernize its military capabilities across the board, if Beijing also thinks it will be able to achieve “system penetration” capabilities, then it will feel less pressure to consider cooperative measures to address the missile defense problem.

Even more important, China appears increasingly determined to develop and deploy advanced missile defense technologies. This could further reduce Chinese interest in an international agreement to limit missile defense development or deployment.

An important driver behind China’s growing interest in developing its own missile defense is the perception that the other major powers and many of their security allies are making heavy investments in advanced missile capabilities. This leads Chinese experts to argue that such developments are part of an important international trend—namely, that major military actors will increasingly rely on missiles in their defense strategies—and that China must be able to deal with this threat. The trend is particularly obvious in the Asia-Pacific region, with U.S. security allies such as Japan and South Korea pursuing various missile technologies. The termination of the Intermediate-Range Nuclear Forces (INF) Treaty allows the United States to quickly develop theater-range missile technologies as well. Many Chinese experts argue that U.S. determination to build up such missile capabilities against China led to Washington’s withdrawal from the INF Treaty in the first place, a view that reinforces the perception that the international trend of missile development enjoys strong forward momentum and thus China would be amiss not to develop its own advanced counter-capability.19

The introduction of hypersonic technologies—including boost gliders and hypersonic cruise missiles—adds to China’s incentive to develop missile defenses. Hypersonic missiles are not a completely new type of weaponry. Existing missiles have demonstrated such capabilities as high speed, maneuverability, and high accuracy, although hypersonic missiles expand some of these capabilities beyond existing levels. But hypersonic missiles have generated new threat perceptions. They are generally believed to be faster and better capable of defeating missile defenses than traditional ballistic missiles and thus may pose a greater threat to critical military targets such as mobile command, control, and communication centers. In most cases, they carry conventional warheads or even use kinetic energy to destroy the target, which may make them more militarily usable on the battlefield. That such weapons may be relatively expensive and hard to procure and deploy in large numbers increases major powers’ confidence and interest in seeking an affordable capability to defend against them. For all these reasons, Chinese experts argue that it is increasingly important for a major power to acquire an integrated anti-air, anti-missile, anti-near space, and anti-space capability that can address threats from all related domains.20

Chinese experts also believe that, from a technical perspective, the development of missile technologies and missile defense technologies are increasingly intertwined and mutually beneficial.21 They argue that the emerging threat from a variety of new conventional missile systems, including hypersonic missiles that are being developed and deployed by the United States, Japan, and other countries, means China faces a practical need to develop defensive capabilities in addition to continuing to develop more advanced offensive weapons.22 In some cases, Chinese thinking seems to have been influenced by misunderstandings about U.S. capabilities and policies. For instance, Chinese experts observe that the United States is adopting a new policy to arm ICBMs with conventional warheads as part of a plan to build up its prompt global strike capabilities.23 This observation appears to result from an inaccurate reading of the previous American Conventional Prompt Global Strike plans. During the Obama administration, some American military officials considered the option of conventional ICBMs.24 But U.S. leaders chose not to pursue this option because they were concerned that the ambiguity of ICBMs capable of carrying either conventional or nuclear warheads would create incentives for the country being attacked to assume the worst and respond with nuclear strikes even if the U.S. missiles were carrying conventional warheads. Nonetheless, some Chinese experts seem to either believe these programs are still ongoing or think the U.S. government has started some new programs to develop similar capabilities. The Chinese misreading of this U.S. policy could make China more determined to develop long-range missile defense capabilities in addition to investing more in its own long-range strike technologies. Bilateral expert exchanges and dialogues may help to clarify such misunderstandings and prompt China to reflect on its perceived need to develop certain missile defense technologies.

China believes the United States, Russia, and other major powers have all been accelerating their investment in missile defense capabilities and that it must “borrow their experiences” and learn from their thinking.25 As China’s overall economic growth outpaced that of other major powers and as Beijing significantly narrowed the economic gap with Washington in recent decades, Chinese strategists increasingly argue that China should develop capabilities that are commensurate with its great-power status.26 The development of advanced missile defense capabilities is viewed in a similar vein.27 Chinese experts also believe that China’s overall economic strength will eventually lead to China’s successful acquisition of advanced missile defense capabilities. They think China’s increasingly close security cooperation with Russia provides another advantage in China’s pursuit of such capabilities, including through Chinese-Russian joint development and even joint deployment of certain missile defense technologies.28 By proactively exploiting new technologies and innovative tactics, China expects to “transition from passively catching up (with the frontrunners) toward an active leapfrog development mode” that would make it a leader in missile defense capabilities.29

Chinese experts have conducted extensive technical studies on various types of missile defense technologies and operational strategies.30 The mainstream view appears to be that China should conduct comprehensive research and development on all types of missile defense technologies—including technologies to defend against hypersonic missiles—and focus on the deployment of multilayered but limited missile defense capabilities over key areas in the near term. Examples of key areas to be protected likely include the capital city and important military facilities such as command and control centers and strategic missile fields. One of the reasons for China’s reported construction of relatively densely populated silo-based ICBM sites may be to make missile defense protection easier, since the alternative would involve the construction of large-area missile defense capabilities to protect road-mobile strategic missiles that are usually scattered across much larger areas.

China seems to be taking an incremental, wait-and-see approach to its long-term deployment plans, keeping options open and not rushing into any specific plan until it has a better idea of how its overall security environment will evolve and what technologies will become available. This appears to be a relatively pragmatic approach, especially when compared with China’s apparent decision to build up its nuclear forces quickly and substantially. China’s missile defense decisions will also be influenced by whether the United States and its allies deploy medium- and longer-range missiles—and how many—in the Asia-Pacific region, as well as whether China’s economy continues to perform well enough to provide funding for major new defense projects. But the wish to keep options open, including deployment options, is likely to make China hesitant to engage in serious negotiations that may limit its future missile defense capabilities. That said, American willingness to accept reciprocal constraints on its own missile defenses could help incentivize China to do the same.

These Chinese considerations do not mean China will not talk with the United States. To facilitate such bilateral discussions, however, a better understanding of Chinese thinking would help international analysts propose more practical cooperative measures that are appealing to China and more likely to yield results. The history of the bilateral nuclear relationship suggests that the long-standing U.S. reluctance to put missile defense on the negotiating table contributed to China’s growing interest in unilateral measures to address its concerns about American missile defenses. China has already embarked on a path to significantly enhance its nuclear capabilities and develop various counter-capabilities—some of which, such as ASAT, will create long-term challenges to the overall security relationship.

Fortunately, no evidence indicates that China has officially and completely closed the door for exploring cooperative measures to tackle the missile defense challenge; rather, it appears to remain ambivalent about whether it will do so. To build guardrails and reduce the risk of the bilateral security relationship spiraling out of control, both Washington and Beijing should more explicitly indicate their willingness to consider cooperative measures, and experts from both countries should start to seriously explore concrete cooperative measures they each could take. The following sections examine specific areas in which progress might be made.
 

Endnotes

• 13Office of the Secretary of Defense, Annual Report to Congress: Military and Security Developments Involving the People’s Republic of China, 2021 (Washington, D.C.: Department of Defense, 2021).
• 14樊菁 [Fan Qing], 丛彬彬 [Cong Binbin], 王建 [Wang Jian], 陈豪 [Chen Hao], 万田 [Wan Tian], and 李帅辉 [Li Shuaihui], “洲际滑翔飞行器天基红外探测的信噪比分析” [Signal-to-noise analysis of space-based infrared detection for intercontinental glide vehicles], 中国科学: 物理学力学天文学 [Scientia sinica: Physica, mechanica & astronomica] 50 (5) (2020): 126–134.
• 15李乔扬 [Liu Qiaoyang], 陈桂明 [Chen Guiming], and 许令亮 [Xu Lingliang], “弹道导弹突防技术现状及智能化发展趋势” [Current status and intelligent development trend of ballistic missile surge defense technology], 飞航导弹 [Aerodynamic missile] (7) (2020): 56–61.
• 16Stephen Chen, “Chinese Team Claims ‘Highly Reliable’ Communications During Hypersonic Flight,” South China Morning Post, August 30, 2022.
• 17温广辉 [Wen Guanghui], 周佳玲 [Zhou Jialing], 吕跃祖 [Lu Yuzu], 刘照辉 [Liu Zhaohui], and 吕金虎 [Lu Jinhu], “多导弹协同作战中的分布式协调控制问题” [Distributed coordination control in multi-missile cooperative operations], 指挥与控制学报 [Journal of command and control] 7 (2) (2021): 137–145.
• 18梁蕾 [Liang Lei], “洲际弹道导弹突防技术发展趋势” [Trends of ICBM penetration technologies development], 飞航导弹 [Aerodynamic missile] (8) (2018): 55–57, 63; 汪民乐 [Wang Minle], “弹道导弹突防对策综述” [Overview of ballistic missile penetration countermeasures], 飞航导弹 [Aerodynamic missile] (10) (2012): 45–51; and 罗曦 [Luo Xi], “美国导弹防御助推段拦截技术及其战略影响” [U.S. missile defense boost-phase intercept technologies and strategic implications], 中国国际战略评论2019(上) [China international strategic review] 1 (2019): 204–221.
• 19邹治波 [Zou Zhibo], “美国退出« 中导条约» 的当代含意与影响” [Implications and impacts of U.S. withdrawal from Intermediate-Range Nuclear Forces Treaty], 国际经济评论 [International economic review] 1 (2020): 31–42.
• 20陈翔 [Chen Xiang], 董立勇 [Dong Liyong], and 于宁宇 [Yu Ningyu], “美军导弹防御拦截武器发展趋势分析” [Analysis of the development trend of U.S. military missile defense interceptor weapons], 军事文摘 [Miliary digest] (23) (2020): 44–47.
• 21刘野 [Liu Ye], 袁欣 [Yuan Xin], and 张蕾 [Zhang Lei], “美国多方位防御-快速拦截弹交战系统发展情况分析” [Analysis of the development of the U.S. multi-directional defense-rapid interceptor engagement system], 飞航导弹 [Aerodynamic missile] (3) (2020): 1–4.
• 22王永海 [Wang Yonghai], 张耀 [Zhang Yao], 李漫红 [Li Manhong], 路瑞敏 [Lu Ruimin], and 王立研 [Wang Liyan], “日本高超声速导弹发展计划分析与研究” [Analysis and study of Japan’s hypersonic missile development program], 飞航导弹 [Aerodynamic missile] (11) (2019): 39–42; 陈星宇 [Chen Xingyu], “(美国高超声速导弹武器研制进展及思考” [Progress of U.S. hypersonic missile weapons development and reflections], 中国航天 [Aerospace China] (5) (2021): 62–66; 闫孟达 [Yan Mengda], 杨任农 [Yang Rennong], 张滢 [Zhang Ying], 胡东愿 [Hu Dongyuan], 张泽 [Zhang Ze], 岳龙飞 [Yue Longfei], and 马铭希 [Ma Mingxi], “美国中段反导预警探测系统作战流程分析” [Analysis of the operational process of the U.S. mid-course anti-missile early warning detection system], in 第九届中国指挥控制大会论文集 [Proceedings of the Ninth China Command and Control Conference] (July 5, 2021); and 汤志成 [Tang Zhicheng], “假如美在亚太部署陆基中程导弹” [If the U.S. deploys land-based intermediate-range missiles in the Asia-Pacific], 兵器知识 [Ordnance knowledge] (10) (2019): 1.
• 23代勋勋 [Dai Xunxun], “新核政策能否助俄化解军控压力” [Can new nuclear policy help Russia defuse arms control pressure], 世界知识 [World affairs] (13) (2020): 46–47. Prompt global strike is a U.S. military effort, especially during the George W. Bush and Barack Obama administrations, to develop capabilities that could deliver a precision conventional weapon to most parts of the world within a very short period of time, such as an hour. There was once a military proposal of modifying ICBMs to deliver conventional warheads but the proposal did not materialize into an actual program.
• 24Amy F. Woolf, Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues, Congressional Research Service R41464 (Washington, D.C.: Congressional Research Service, January 8, 2019; updated July 16, 2021).
• 25郭衍莹 [Guo Yanying], “俄战略反导系统亮点何在” [What are the highlights of the Russian strategic anti-missile system], 中国国防报 [National defense news], May 25, 2020, 4; 唐永胜 [Tang Yongsheng], “国际安全与军控形势：博弈激烈，治理缺失” [International security and arms control situation: Intense gaming, lack of governance], 世界知识 [World affairs] (24) (2020): 42–44; and 邹伟 [Zou Wei], 赵国艳 [Zhao Guoyan], and 韩仲瑶 [Han Zhongyao], “探索天基反导武器在未来作战中的应用” [Exploring the application of space-based anti-missile weapons in future operations], in 2020中国航空工业技术装备工程协会年会论文集 [2020 China Aviation Industry Technical Equipment Engineering Association annual meeting proceedings] (2020), China Aviation Industry Technical Equipment Engineering Association, Xi’an, 488–491.
• 26In recent years, China’s economic development has slowed, but China’s officially declared economic growth rates are still slightly higher than the United States’ economic growth rates.
• 27陈翔 [Chen Xiang], 董立勇 [Dong Liyong], and 于宁宇 [Yu Ningyu], “美军导弹防御拦截武器发展趋势分析” [Analysis of the development trend of U.S. military missile defense interceptor weapons].
• 28柳丰华 [Liu Fenghua], “俄美中导竞争与中国应对方略” [Russia-U.S. INF competition and China’s response strategy], 北方论丛 [Northern literary studies] (4) (2021): 26–34, 166.
• 29陈翔 [Chen Xiang], 董立勇 [Dong Liyong], and 于宁宇 [Yu Ningyu], “美军导弹防御拦截武器发展趋势分析” [Analysis of the development trend of U.S. military missile defense interceptor weapons].
• 30曹莉 [Cao Li], 周亮 [Zhou Liang], 耿斌斌 [Geng Binbin], 吴昕芸 [Wu Xinyun], and 赵钱 [Zhao Qian], “空基助推段反导拦截能力需求与仿真分析” [Requirement and simulation analysis of air-based booster segment anti-missile interception capability] 空天防御 [Air and space defense] 3 (1) (2020): 87–92; and 邹伟 [Zou Wei], 赵国艳 [Zhao Guoyan], and 韩仲瑶 [Han Zhongyao], “探索天基反导武器在未来作战中的应用” [Exploring the application of space-based anti-missile weapons in future operations].

At the end of the day, the principal positions of the United States and China on missile defense are not in conflict. The official U.S. policy remains that it relies on its offensive nuclear capabilities to deter Chinese nuclear attack and that American strategic missile defenses are not aimed at undermining the Chinese nuclear deterrent but rather are focused on protecting the U.S. homeland from North Korean and (future) Iranian threats. American regional missile defenses, on the other hand, do not distinguish which country the threat comes from and aim to counter all possible threats. In theory, the inclusive nature of the targets of American regional missile defense could pose a threat to China’s capacity to conduct limited nuclear retaliation against regional targets and thus could undermine China’s nuclear deterrent at the regional level.31 But Chinese officials have not specifically identified such a threat. Rather, concerns have focused primarily on the impact of American strategic missile defenses on China’s strategic nuclear deterrent against the United States. Beijing appears to implicitly accept the U.S. thinking that regional missile defenses are not a strategic concern to China if they do not threaten China’s nuclear second-strike capability against the American homeland. Therefore, addressing the Chinese concern about American strategic missile defenses should remain the priority of bilateral discussions.

So far, the United States possesses only one type of dedicated strategic missile defense system: the Ground-based Midcourse Defense (GMD), which is based on ground-based interceptors (GBI). The U.S. buildup of its GMD system has been relatively slow. After decades of work, only forty-four GBIs have been deployed. The next planned step is to add twenty more in a few years.32 The employment doctrine seems to envision using more than one GBI against one incoming target.33 This significantly limits the threat the GMD system currently poses to Chinese nuclear forces, which reportedly comprise more than one hundred ICBM launchers and around seventy-two SLBM launchers at the time of this research.34 One important uncertainty for China is whether the United States will be able to substantially increase the efficiency of the GMD system; for example, by successfully developing and deploying the technology to take out multiple objects with one interceptor vehicle.35 However, the GMD’s development track record suggests that sudden perfection and operationalization of such advanced technologies are unlikely. Continued transparency on the qualitative and quantitative improvement of the GMD program should help mitigate exaggerated Chinese threat perceptions of the program’s potential impact on China’s nuclear deterrent.

Space-based interceptors and directed energy weapons are examples of other technologies that may contribute directly to the U.S. strategic missile defense. But these technologies are also unlikely to become fully operational in a short period of time, even if they receive sustained investment in the future. Therefore, China should have sufficient time to react if and when such technologies become a realistic threat to its nuclear deterrent.

So far, nothing indicates that Washington plans to expand the target of its strategic missile defenses from focusing on rogue states to also including China and/or Russia. Under existing U.S. policy, the key variable in Washington’s calculus on whether to dramatically scale up its strategic missile defenses is whether North Korea will massively build up its intercontinental-range nuclear forces. However, if China were to demonstrate serious interest in developing conventional intercontinental-range missiles capable of targeting the U.S. homeland, this could lead to important changes in Washington’s strategic missile defense deployment policy, making it much harder, if not impossible, for the two sides to seek cooperative measures to mitigate the impact of U.S. strategic missile defenses on bilateral nuclear stability.

One important uncertainty rests with the Chinese development of hypersonic missiles (boost gliders and hypersonic cruise missiles) and the U.S. development of defensive capabilities against such weapons. As China’s development of hypersonic technologies appears to be driven to a considerable extent by the desire to penetrate missile defense systems, China may see nuclear-capable hypersonic missiles as important for enhancing its nuclear deterrent in the long run. Beijing sees conventionally armed hypersonic missiles as useful, too, so China might eventually want to acquire hypersonic missiles—including those of intercontinental range—for both nuclear and conventional purposes. Washington has never imposed an explicit limit on its own development and deployment of defensive capabilities against hypersonic missiles (in contrast to traditional ballistic missiles), nor has it acknowledged such defensive capabilities’ potential impact on the issue of nuclear deterrence in major power relations. But the United States may have little incentive to limit hypersonic defenses if China imposes no limit on its development of conventional hypersonic missiles. China’s apparent interest in investing in its own hypersonic defenses complicates the equation further.

Clearly, the need is growing for the two sides to start exchanging views about how they understand the impact of hypersonic missiles and hypersonic defenses on their nuclear relationship. Currently, U.S. hypersonic defense strategy includes serious work on mid-course interception, which requires the development of interceptors that work at much lower altitude than traditional long-range mid-course anti-ballistic missile interceptors. Technical differences like this make it necessary for the two countries to have an exchange on the impact of hypersonic defense, in addition to bilateral discussions on ballistic missile defense. Even if they cannot make progress on the latter, they can still seek to begin a separate, open-ended dialogue on the former. And since hypersonic defense is still at a relatively early stage of development in both countries, exploration of a joint framework to understand and even regulate future policies for hypersonic defense should face fewer entrenched bureaucratic interests.

As for missile defense in general, one major challenge for the foreseeable future is posed by Washington’s growing interest in expanding the capabilities of missile defense systems originally designed for regional purposes to contribute to U.S. strategic defense. The Aegis regional defense system (especially the SM-3 Block IIA interceptor; hereinafter shortened to “SM-3 IIA”) causes the greatest concern. SM-3 IIA interceptors may have some capacity to engage intercontinental-range targets and thus be used as an underlayer for existing U.S. strategic missile defenses. The United States also could procure and deploy the less costly SM-3 IIA interceptors in much larger numbers than the GBI and thus quickly expand its overall arsenal of strategic interceptors.36 The U.S. military also envisions having the Terminal High Altitude Area Defense (THAAD) system play a supplementary role in strategic missile defense. However, the THAAD system can intercept ICBMs only during their terminal phase, making its potential defended area much smaller than that of an SM-3 system. Therefore, Washington should first explore the possibility of addressing Chinese concerns about the SM-3 system, which increasingly drive China’s threat perception. A successful test of the SM-3 IIA interceptor against an ICBM-class target in November 2020 and continuing efforts to improve the interceptor’s capability in this area add to the urgency.

The lack of exchanges among technical experts from the two countries means that China is more likely to have overestimated the threat of the SM-3 IIA interceptors to its nuclear deterrent. For example, SM-3 IIA has been portrayed in official U.S. materials and expert studies as having the kinematic capacity to intercept an ICBM-class target during both the ICBM’s ascent and descent phases.37 This may be true for some ICBM-class missiles under certain conditions, but calculations that apply specifically to the scenario of a Chinese ICBM attack on the U.S. homeland reveal that SM-3 IIA interceptors (assuming a burnout velocity of 4.5 kilometers per second) do not have the kinematic capacity to engage ICBMs launched from known Chinese ICBM sites toward the U.S. homeland during the ascent phase, even if the SM-3 IIA interceptors are deployed off the Chinese coast.38 Rather, the kinematic capacity of SM-3 IIA interceptors is such that they could potentially engage Chinese ICBMs only during the descent phase of the ICBM flight and only if the interceptors are deployed near the U.S. West or East Coast. The United States would thus need to deploy Aegis Ashore systems and/or deploy shipborne Aegis systems off its coasts. To build sufficient Aegis Ashore systems might not be a small investment, and to deploy enough Aegis ships off its coasts would considerably constrain the U.S. capability to use its already stretched Aegis fleet to carry out other key military operations. That is, the actual U.S. capacity to use SM-3 IIAs to intercept Chinese ICBMs is quite limited. Furthermore, U.S. construction of Aegis Ashore sites on its coasts and deployment of Aegis ships to U.S. coastal regions cannot be hidden from China, which provides Beijing with an opportunity to develop good situational awareness and prepare countermeasures.

Chinese technical experts either have not conducted in-depth analysis of the actual capability of SM-3 IIA interceptors against Chinese ICBMs, or they have drawn conclusions different from the above analysis, as they continue to argue that SM-3 IIA interceptors pose a serious threat because they can be forward-deployed in the Asia-Pacific region and intercept ICBMs at an earlier stage than the U.S. GMD system.39 Such technical assessments then shape the views of Chinese policy experts, thus influencing China’s overall threat perception. For this reason, technical experts from the two countries should seek to use publicly available information to conduct a joint assessment of the realistic coverage area of SM-3 IIA interceptors under various deployment scenarios. This may help build common views on the severity of the impact of such interceptors.

Other factors could further limit the SM-3 IIA’s ability to intercept Chinese ICBMs. For instance, calculations of the SM-3 IIA’s kinematic coverage usually assume that the U.S. radar network can provide full, accurate, and timely tracking and cuing information for all Chinese ICBM flight trajectories. However, Washington may need considerable time and effort to acquire such a capability. The current long-range radars may also be vulnerable to kinetic and nonkinetic attacks. Furthermore, the United States uses the descriptor “ICBM-class target” to refer to any ballistic missile with a range of at least 5,500 kilometers. But a Chinese ICBM capable of targeting the U.S. homeland needs to have a range of at least 8,000 kilometers and ideally more than 11,000 kilometers. Depending on what ICBM target was used in the November 2020 test, the SM-3 IIA may not yet have a proven capability against most Chinese ICBMs. The likelihood that the 2020 test was conducted under idealized and “highly favorable” conditions also means that predictions of the SM-3 IIA’s performance against real-world targets—especially against ICBMs equipped with decoys and other countermeasures—are less reliable.40

The lack of Chinese analysis of these constraining factors makes China more likely to overestimate U.S. capabilities. Certain interests inside the Beltway may also be keen to use China’s concern about U.S. development and deployment of such systems to advance U.S. foreign policy goals. When Washington was considering THAAD deployment to South Korea, some senior American officials sought to use Chinese anxiety about THAAD to pressure Beijing to impose more sanctions on North Korea to contain Pyongyang’s nuclear program.41 Any U.S. interest in exploiting Chinese concern about SM-3 IIA, however, would work against the U.S. interest in mitigating China’s overestimation of threats. Therefore, the United States needs to comprehensively evaluate how China’s threat perception of U.S. missile defense may affect U.S. interests and then send unambiguous and consistent messages to China.

Chinese experts have extensively discussed how seriously the U.S. SM-3 IIA could threaten China’s deterrent capabilities. Far less discussion has occurred about how China wants the perceived threat to be contained, especially what China might want the United States to do to sufficiently reduce the perceived threat. Beijing’s interests would be served by making specific requests and/or proposing specific measures it would like Washington to take regarding the development and/or deployment of SM-3 IIA. Even if Washington did not immediately accept the Chinese proposals, they could still serve as a useful starting point for substantive engagement at either the expert or official level.

Rising tensions over the Taiwan Strait in recent years make such efforts all the more important. Regional missiles and regional missile defense systems would play a significant role in any war across the Taiwan Strait. The measures discussed in this section could help efforts to delink the intensified competition between missile and missile defense capabilities at the regional level from the broader U.S.-China strategic nuclear relationship.
 

Endnotes

• 31For a more detailed discussion, see, for example, Zhao, Narrowing the US-China Gap, 18–24.
• 32Matt Korda and Hans M. Kristensen, “US Ballistic Missile Defenses, 2019,” Bulletin of the Atomic Scientists 75 (6) (2019): 295–306.
• 33George Lewis, “Ballistic Missile Defense: How Many GMD System Interceptors Per Target?” mostlymissiledefense, May 23, 2012.
• 34Hans M. Kristensen and Matt Korda, “Nuclear Notebook: Chinese Nuclear Forces, 2021,” Bulletin of the Atomic Scientists, November 15, 2021.
• 35Jen Judson, “Pentagon Hits Pause on Redesign of Critical Homeland Missile Defense Component,” DefenseNews, May 28, 2019.
• 36George Lewis, “Strategic Capabilities of SM-3 Block IIA Interceptors,” mostlymissiledefense, June 30, 2016.
• 37National Research Council, Making Sense of Ballistic Missile Defense: An Assessment of Concepts and Systems for U.S. Boost-Phase Missile Defense in Comparison to Other Alternatives (Washington, D.C.: National Academies Press, 2012), 27.
• 38Computer modeling conducted by Jaganath Sankaran, assistant professor at the Lyndon B. Johnson School of Public Affairs at the University of Texas, Austin.
• 39熊瑛 [Xiong Ying], “标准 3 Block 2A首次洲际弹道导弹拦截试验分析” [Standard 3 Block 2A first ICBM intercept test analysis], 飞航导弹 [Aerodynamic missile] (2) (2021): 53–58.
• 40U.S. Government Accountability Office, Missile Defense: Fiscal Year 2020 Delivery and Testing Progressed, but Annual Goals Unmet, GAO-21-314 (Washington, D.C.: U.S. Government Accountability Office, April 2021).
• 41David E. Sanger and Michael R. Gordon, “U.S. May Soon Increase Pressure on China to Constrain North Korea,” The New York Times, March 15, 2017.

U.S. reliance on space-based assets to execute missile defense operations has incentivized China to develop various ASAT technologies. China’s growing ASAT capabilities have caused concern in the United States and led Washington to pressure Beijing to constrain its ASAT program. The Chinese concern about U.S. missile defense and the U.S. concern about Chinese ASAT intentions may create space for mutual compromise. More important, the inherent overlap between missile defense and ASAT technologies means that any agreement to impose limits on one technology would inevitably have implications for the other. For instance, U.S. efforts to reach a bilateral or multilateral agreement to constrain the development of certain ASAT technologies may also undermine U.S. capacity to test and develop certain missile defense capabilities. Similarly, Chinese interest in limiting U.S. missile defense development may also make it harder for Beijing to continue its testing and development of certain ASAT capabilities. However, neither country has stated whether or how it is prepared to deal with the consequences to its own capability development even as it expresses concern about the other’s respective capabilities. Consideration of an integrated framework is therefore necessary. China’s growing interest in developing its own missile defense technologies and the continued interest in certain ASAT capabilities within some quarters of the American defense community could increase the need to consider elements of missile defense and ASAT together.

China’s investment in ASAT technologies is motivated by more than one military objective, but countering U.S. missile defense has remained a key driving force.42 The two sides could thus profitably explore a joint agreement to limit missile defense and ASAT capabilities. However, China’s interest in keeping open the option to develop its own missile defense technologies could stand in the way.

China’s interest in missile defense might be motivated by ambitions quite different from the U.S. ambition to protect its entire homeland from missile attack. China might instead be interested only in acquiring point missile defense capabilities to protect a limited number of strategic targets, such as key command and control centers, nuclear missile sites, and its political leadership. This would make sense for China, as the financial cost and technological challenges of building a strategic missile defense capable of dealing with the thousands of nuclear weapons in the U.S. arsenal would likely be immense. However, Chinese strategists are not interested in restricting themselves to thinking only about limited deployment of missile defenses; they want to keep all options open for the future. They want to continue developing strategic missile defense technologies for various reasons, including to help inform China’s development of missile defense countermeasures. Self-confidence is growing among Chinese strategists, who see China on a steady trajectory that will make it a peer of the United States and eventually surpass it. As a result, they seem to reject the notion that certain capabilities are available only to the United States and beyond the reach of China.

China needs to understand that the rejection of any limits on its own development and deployment of missile defense capabilities would undermine its ability to demand that the United States limit its missile defenses. It would be in China’s interest to clarify its vision for its future missile defense capabilities and to seek common areas for reciprocal restraint with the United States, keeping in mind that one side’s thinking and objectives significantly shape those of the other. On the other hand, if China sees its goal of missile defense development and deployment to be limited in the long run, or if it at least wants to prioritize the development of protection of key sites for the foreseeable future, that could open up an opportunity to negotiate joint limits with the United States on certain types of strategic missile defense technology development, such as long-range ballistic missile mid-course hit-to-kill interceptors, which would be technologically challenging to employ against a peer competitor under realistic battlefield conditions but, according to worst-case-scenario analysis, could be very threatening to major power strategic stability. In addition, these technologies can be easily adapted to serve as the most worrisome type of direct-ascent ASAT weapon. Any U.S. reassurance that it would not develop conventional long-range missiles, especially those of intercontinental range, could further enhance Chinese interests in such a restraint on strategic missile defense.

If a joint limit on the qualitative development of certain missile defense technologies is too challenging, the two sides could still explore quantitative limits or transparency on deployed strategic capabilities. Given the highly asymmetric capabilities of the two sides’ nuclear arsenals and deployed missile defense systems, the two sides might consider a framework in which Washington limits the number of certain types of its deployed missile defense systems in return for Beijing declaring a limit on its nuclear stockpile. As a first step in this direction, the two sides could consider an agreement on reciprocal transparency in which Washington would brief Beijing on U.S. missile defense procurement plans for a given period of time in return for Beijing briefing Washington on its nuclear systems procurement plans during the same period.43 This confidence-building measure could at least help reduce the risk from worst-case guessing about each other’s future capabilities.

China and the United States should also be able to find room for jointly limiting the development or deployment of some of the most dangerous and destabilizing ASAT technologies. China has displayed little interest in this area over the past decades, but the renewed interest in some quarters of U.S. policy circles in developing American ASAT capabilities might pressure Beijing to review its cost-benefit calculation.

ASAT technologies that threaten the enemy’s space-based nuclear command, control, and communication (NC3) systems could be particularly destabilizing. China may be interested in attacking such U.S. assets in a crisis because doing so might also undermine U.S. missile defense capabilities, including regional capabilities in East Asia. Because those capabilities are part of the U.S. NC3 system, however, the United States might misunderstand the Chinese objective in developing the requisite ASAT technologies, leading to inadvertent escalation. Many of the U.S. early warning satellites are deployed in geostationary orbit (GEO) and highly elliptical orbits (HEO). Thus, Chinese ASAT technologies that target assets in GEO and HEO could be particularly provocative. The U.S. employment of similar ASAT technologies could be equally problematic to China once China perfects its own space-based early warning capabilities. Some American experts have made detailed proposals to ban the testing or deployment of ASAT technologies that directly threaten satellites in GEO and HEO, including ground-based direct-ascent ASAT, upward-facing ground-based lasers, and proximity operations in GEO and HEO.44 Such proposals are worth serious consideration, especially as part of a reciprocal pact of mutual concessions.

In addition, the U.S. Missile Defense Agency is developing the Hypersonic and Ballistic Tracking Space Sensor system in low earth orbit (LEO) to detect and track ballistic and hypersonic missiles. Some other satellites in LEO, such as earth observation satellites and radar satellites, also play a role in detecting and tracking nuclear missile platforms before missiles are launched. Worried that their nuclear deterrent could be undermined by satellites in LEO, Russia and China may have an interest in holding them under threat.45

One type of U.S. missile defense system that could have direct implications for China’s interest in ASAT capabilities is space-based missile defense interceptors in LEO. Development of such technology could motivate China to pursue ASAT capabilities more aggressively to protect its nuclear deterrent. Although the Trump administration’s 2019 Missile Defense Review Report expresses interest in better understanding the feasibility of space-based interceptors, the U.S. government does not appear to have made a formal decision to pursue such a capability. For the foreseeable future, this capability is likely to remain so controversial—not least because of its technical complexity and tremendous cost in addition to its vulnerability—that the odds of Washington deciding to acquire it are relatively low.

Nevertheless, the Chinese understanding of U.S. thinking may be different. For example, some Chinese military experts believe the United States is already in the process of deploying space-based interceptors.46 Experts from the China Aerospace Science and Technology Corporation—one of the two main conglomerates in China’s rocket and missile industry—claim that the Starlink satellites’ collision-avoidance capability could be easily adapted to intercept ballistic missiles. They also claim—citing a study by a team of senior Chinese rocket engineers—that, in computer simulations, Starlink satellites successfully intercepted more than 350 ICBMs with no failures and that the satellites could conduct five to seven intercept attempts against each incoming nuclear warhead. They even believe that Starlink satellites could intercept enemy warheads if enough of the satellites smashed into one another to produce a large amount of debris, thus blocking the orbit(s) traveled by enemy warheads.47 These scenarios likely represent misunderstandings about how the United States intends to employ its space assets, especially its civilian space assets. Nonetheless, such misunderstandings could influence Chinese official thinking about U.S. intentions and China’s counterstrategy.

The two sides urgently need to clarify their thinking about their own and each other’s capabilities and policies through expert-level exchanges. In the meantime, they can also examine the proposals by independent think tank experts to prohibit the deployment of space-based interceptors.48 An explicit moratorium on the deployment of space-based interceptors could help reduce both legitimate concerns and misunderstandings about such capabilities.

Another important Chinese incentive to pursue ASAT capabilities is the widespread Chinese perception that other major powers have been developing serious ASAT capabilities for battlefield use by integrating the development of ASAT and missile defense.49 For instance, they believe the American and Russian missile defense programs are partly driven by a desire to secretly acquire ASAT capabilities. The two technologies do have significant areas of overlap, and missile defense systems—being defensive weaponry—can provide a useful moral and legal justification for the development of such technologies.50 The perception that the other major powers have an inherent interest in ASAT and that their missile defense programs provide a cover for developing ASAT capabilities could make China even more pessimistic about U.S. willingness to limit its missile defense program. Such a perception has also reinforced China’s own determination to pursue ASAT capabilities through an integrated approach of simultaneously developing both missile defense and ASAT technologies.51

Chinese suspicions are likely one main reason that Beijing has not reacted positively to the Biden administration’s announcement of a unilateral moratorium on debris-generating direct-ascent ASAT testing. Beijing thinks Washington already possesses advanced ASAT capabilities through its missile defense programs and can continue developing them under the cover of missile defense. Therefore, Beijing interprets the U.S. moratorium as an effort to prevent Beijing from acquiring ASAT capabilities that Washington already has, leaving a big loophole that Washington can easily exploit.

To address such Chinese suspicions, Washington can further demonstrate its good will by offering to discuss technical measures that can clarify ambiguities and make its moratorium commitment clearer and easier to execute. Such measures should also address Beijing’s concern that the moratorium could undermine China’s capability to develop missile defenses. Therefore, Washington could consider inviting Beijing to an expert-level discussion about the feasibility of establishing a simple altitude limit above which no kinetic interception testing should take place. They could also discuss the possibility of establishing a more complex set of technical criteria, including not only an altitude limit but also factors such as the direction of interception and the relative speed of the colliding objects. If successful, such joint discussions could enhance Chinese confidence that a more specific ASAT testing moratorium would impose the same technological limits on both countries. In this case, where the two sides decide to set the technical limit would be a result of negotiations in which both countries would likely seek to strike a balance between containing debris generation and minimizing limits on their missile defense and other military developments.
 

Endnotes

• 42白新有 [Bai Xinyou], 王枭 [Wang Xiao]), and 楚樊星 [Chu Fanxing], “掩护弹道导弹突防支援干扰措施研究” [Research on support jamming measures for covering ballistic missile penetration], 战术导弹技术 [Tactical missile technology] (3) (2021): 126–132; 程强 [Cheng Qiang] and 游敬云 [You Jingyun], “对弹道导弹防御系统的电子对抗技术分析” [Analysis of electronic countermeasures against ballistic missile defense system], 舰船电子对抗 [Ship electronic countermeasure] 50 (2) (2017): 6–9; and 梁蕾 [Liang Lei], “洲际弹道导弹突防技术发展历程” [History of ICBM penetration technologies development], 飞航导弹 [Aerodynamic missile] (1) (2018): 33–37.
• 43In 2013, the U.S. government proposed a similar missile defense transparency agreement with Russia. See, for example, Steven Pifer, “The Future of U.S.-Russian Arms Control,” Brookings Institution, February 26, 2016.
• 44See, for example, James M. Acton, Thomas Macdonald, and Pranay Vaddi, Reimagining Nuclear Arms Control: A Comprehensive Approach (Washington, D.C.: Carnegie Endowment for International Peace, December 2021).
• 45Bart Hendrickx, “Peresvet: A Russian Mobile Laser System to Dazzle Enemy Satellites,” Space Review, June 15, 2020.
• 46罗曦 [Luo Xi], “大国竞争格局下的国际军控走势” [The trend of international arms control under the pattern of competition among major powers], 解放军报 [PLA daily], July 8, 2021, 11.
• 47李陆 [Li Lu], 郭莉丽 [Guo Lili], and 王克克 [Wang Keke], “‘星链’星座的军事应用分析” [Analysis of the military applications of the “Starlink” constellation], 中国航天 [Aerospace China] (5) (2021): 37–40.
• 48See, for example, Acton, Macdonald, and Vaddi, Reimagining Nuclear Arms Control.
• 49臧继辉 [Zang Jihui], “简述‘反卫星技术’” [Brief description of “anti-satellite technology”], 人民政协报 [Journal of the Chinese people’s Political Consultative Conference], June 24, 2021, 7; and 刘海印 [Liu Haiyin], 曹秀云 [Cao Xiuyun], and 李云 [Li Yun], “2015 年国外空间安全重大动向分析” [Analysis of major foreign space security trends in 2015], 中国航天 [Aerospace China] (4) (2016): 23–26.
• 50董正宏 [Dong Zhenghong], 杨帆 [Yang Fan], 陈进军 [Chen Jinjun], and 王俊峰 [Wang Junfeng], “美国应对外空国际条约的做法简析” [A brief analysis of U.S. approaches to international treaties on outer space], 国防科技 [National defense technology] 41 (5) (2020): 79–83.
• 51臧继辉 [Zang Jihui], “简述‘反卫星技术’” [Brief description of “anti-satellite technology”].

Given the U.S. policy of seeking to develop a strategic missile defense capability against the North Korean missile threat, Pyongyang’s growing nuclear and missile capabilities present an increasingly serious reason for Washington not to constrain its strategic missile defense development and for Beijing to protect its nuclear deterrent from perceived U.S. missile defense threats. If North Korea continues to develop and maintain a credible second-strike capability against the United States—as Kim Jong-un’s speech at the Eighth Congress of the Workers’ Party of Korea in January 2021 suggests—that could make the trilateral situation intractable.

To maintain a stable U.S.-China nuclear relationship would require that an American strategic missile defense system that aims to effectively defend the U.S. homeland against North Korean missile attack cannot seriously undermine the Chinese capability to launch missiles against the U.S. homeland. This task is all the more daunting because Washington appears to want its missile defense to be capable of intercepting an all-out North Korean first strike, whereas Beijing cannot allow U.S. missile defense to be capable of intercepting even the small fraction of Chinese missiles that would be likely to survive—and thus be available for retaliation against—an American first strike. Assuming both Washington and Beijing have the political will to find a technical solution, they would need to figure out the ideal mix of qualitative and quantitative capabilities that would allow U.S. strategic missile defenses to be effective enough against North Korea but not too threatening toward China.

Whether such a sweet spot can be identified is unknown. Partly, this is because the status of the U.S.-China relationship and the level of mutual political distrust could significantly affect the Chinese understanding of what constitutes “too threatening.” That said, two general approaches are available that might yield an answer. The first approach is for Washington and Beijing to work together and ensure the overall size of North Korea’s arsenal of nuclear weapons and delivery systems is kept at a very small scale. If the numerical difference between the North Korean and Chinese nuclear arsenals is significant enough, Washington may be able to find that sweet spot in building its strategic missile defenses. To do so, the two sides would need genuine and deep cooperation to contain North Korea’s nuclear expansion. In addition, Washington would need to be willing to limit its strategic missile defense, and Beijing would need to clarify what specific quantitative restraints it wants Washington to take and what reciprocal concessions it is willing to make. To prepare for such bilateral coordination, experts from the two sides could conduct a joint study to determine whether it makes sense to try to draw a line that imposes a quantitative limit on the scale of U.S. strategic missile defenses so that it can counter the North Korean threat without becoming too threatening to China. Experts would also need to engage in candid analytical discussions about how to define and measure the “threat” to China’s nuclear deterrent. A willingness to participate in such expert-level discussions would indicate a commitment to finding a cooperative solution.

The second approach is to find out whether U.S. strategic missile defense could demonstrate a qualitative distinction in its capability against North Korean and Chinese ICBMs. Certain types of missile defense technologies may be much more effective against North Korea than against China. For instance, some American experts argue that airborne or surface-based short-range boost-phase interceptors can play this role.52 Interceptor-bearing aircraft, drones, or vessels would be forward deployed outside North Korea’s territorial waters at a distance close enough to intercept North Korean ICBMs during the boost phase but too far to threaten Chinese ICBMs, which are often deployed hundreds if not thousands of kilometers from China’s border.

So far no public Chinese analysis of such proposals—let alone an official response—has been offered. Thus, a useful starting point would be for Chinese experts to examine the technical feasibility of such ideas either jointly with their American counterparts or independently in a Chinese study. Among the issues that need further examination are the extent to which the employment of such U.S. missile defense systems would require cooperation or assistance from other countries, like China or Russia. Under certain conditions, for example, the United States may need to deploy short-range, boost-phase interceptors close to the Chinese and Russian border or even to launch interceptors toward Chinese and Russian airspace if North Korean ICBMs transit those countries’ airspace. Such issues would also need to be discussed among policy experts from the relevant countries to examine the political acceptability in Russia and China of the U.S. deployment and employment of this defense capability.

Similarly, some Chinese experts have proposed that the United States keep the qualitative capability of its strategic missile defense at a level that could intercept North Korea’s rudimentary ICBMs but could not deal with the much more advanced Chinese ICBMs, especially as Chinese ICMBs are likely equipped with sophisticated penetration aids.53 Given how secretive these technologies are, experts from both sides should jointly discuss whether a meaningful distinction can be made regarding different North Korean and Chinese penetration technologies without revealing the vulnerabilities in either the Chinese penetration aids or the U.S. interceptors. Such joint expert studies can take place at the unclassified level using publicly available information and can offer useful insights about whether the proposal by Chinese experts offers a practical solution. Even if a joint discussion shows the proposal is unlikely to work, it would send a helpful message to Beijing that technical challenges—rather than lack of political will—are what prevents Washington from taking certain reassuring measures to address Beijing’s concerns.
 

Endnotes

• 52James E. Goodby and Theodore A. Postol, “A New Boost-Phase Missile Defense System—And Its Diplomatic Uses in the North Korea Dispute,” Bulletin of the Atomic Scientists 74 (4) (2018): 210–219; Dean A. Wilkening, “Airborne Boost-Phase Ballistic Missile Defense,” Science and Global Security 12 (1–2) (2004): 1–67; Richard L. Garwin and Theodore A. Postol, “Airborne Patrol to Destroy DPRK ICBMs in Powered Flight” (MIT Science, Technology, and National Security Working Group, Cambridge, Mass., November 27–29, 2017); and Brian Dunn, “A Technological Path Out of the Missile-Defense Security Dilemma,” Defense One, March 19, 2019.
• 53Wu Riqiang, “No Stability without Limits on Missile Defense,” Bulletin of the Atomic Scientists, September 24, 2014.

Another set of issues that has not received much scrutiny involves the risk that missile defense could increase crisis instability between the United States and China. In addition to the classical positions in the literature outlining how strategic defensive weapons in general can affect one’s own or one’s adversary’s propensity toward conflict escalation, the specific thinking and policies of the United States and China could affect the likelihood of conflict initiation and the risk of escalation in several ways.

For instance, the U.S. left-of-launch concept of missile defense seeks to “neutralize offensive missile threats prior to launch” through kinetic strikes or by nonkinetic means such as directed energy weapons, cyber interference, and electronic warfare.54 China sees this as evidence that the United States is using missile defense as a cover for executing offensive operations in the form of preemptive strikes. This reinforces the Chinese view that the U.S. missile defense program is inherently offensive rather than defensive in nature and that this justifies China’s contemplation of a preemptive strike on U.S. missile defense assets during crises. The United States can help mitigate this dangerous dynamic by providing more clarity about the conditions under which it plans to employ left-of-launch capabilities against peer competitors or about the enemy military activities that would trigger U.S. execution of certain left-of-launch operations. Even some elaboration on the differences between left-of-launch and preventive attack would be helpful, as many Chinese experts have expressed concern that left-of-launch is a euphemism for preventive attack.

Additionally, China believes that U.S. airborne or ship-based boost-phase interceptors may be particularly prone to causing inadvertent escalations in the U.S.-China context.55 Such interceptors need to be deployed near their target and launched quickly after detecting a missile launch, leaving little time for information processing and evaluation of the situation. This could increase the risk of mistakenly intercepting a nonthreatening missile launch (e.g., a missile test). The likely need to launch such interceptors into Chinese airspace could also make their employment particularly escalatory. American policy-makers should be made aware of Chinese concerns through bilateral exchanges. U.S. decision-makers could then improve crisis stability by making internal policy development decisions that are informed by Chinese concerns. The two countries could also discuss and debate the merits of technical arguments—the process itself would be a useful confidence-building exercise.

On the Chinese side, its activities to counter U.S. missile defense could lead to inadvertent escalation of a conflict under certain scenarios—the risk of which does not appear to have been systematically analyzed. For example, Chinese experts have discussed conditions under which China might need to attack U.S. early warning satellites to undermine U.S. regional missile defense capabilities during a conventional conflict in East Asia.56 But a Chinese attack on U.S. early warning satellites might be interpreted by Washington as an attempt to destroy the U.S. NC3 system of which the early warning satellites are a part.57 In addition to this specific scenario, Chinese experts have discussed various strike options against potentially vulnerable nodes and links in the U.S. missile defense network, including sensors, launchers, interceptors, and command and control, battle management, and communications systems, through both kinetic and nonkinetic means, in what they call “system penetration” or “system confrontation” strategy.58 Absent any deep understanding about each other’s thinking and intentions, these strike options, especially if employed preemptively, could lead to escalation in ways not foreseen by the attacker.

In a situation where key U.S. early warning satellites and ground-based radars are interfered with and even disabled at the same time, Washington might fear the worst about Chinese intentions and choose to significantly escalate the conflict. But even if only one of these two main early warning capabilities is undermined, the United States would still lose the capacity to double-check the authenticity of data provided by the remaining system, and the risk of a false alarm would increase as a result. This risk is made more serious by Chinese thinking that stresses the importance of employing deceptive tactics to enhance China’s missile penetration capabilities.

For example, Chinese military experts have argued for setting up false infrared signal sources to distract, overwhelm, or mislead enemy early warning satellites and to make the enemy unable to adequately identify and track the launch of real missiles.59 Such tactics, if used while U.S. early warning radars are undermined and U.S. early warning satellites have become the only available system, could make it harder for the satellites to produce reliable reports on the location and scale of a Chinese missile launch and thus make U.S. decision-makers more likely to misjudge Chinese intentions and choose inappropriate responses. In many cases, such U.S. misjudgment and inappropriate responses could also hurt China’s own interests, although Chinese reflection on such risks appears minimal.

This highlights the need both to raise awareness of the potential risks in one’s own internal planning and to build joint understanding between the two countries’ military policy communities. As the examples presented in this paper demonstrate, both countries feel anxious about the other’s perceived shift toward preemptive use of force, whereas many experts in both countries also increasingly stress the importance of considering preemptive strike options, including in self-perceived defensive operations. A better understanding of each other’s thinking is urgently necessary if China and the United States are to address crisis instability. It is also an imperative step for discussing measures of mutual restraint in the future.

Endnotes

• 54Department of Defense Appropriations for Fiscal Year 2017: Testimony before the U.S. Senate, Subcommittee of the Committee on Appropriations, 114th Cong. 2 (2016) (unclassified statement of Vice Admiral J. D. Syring, USN, Director, Missile Defense Agency); and U.S. Department of Defense, 2019 Missile Defense Review.
• 55罗曦 [Luo Xi], “美国导弹防御助推段拦截技术及其战略影响” [U.S. missile defense boost-phase intercept technologies and strategic implications].
• 56Tong Zhao and Bin Li, “The Underappreciated Risks of Entanglement: A Chinese Perspective,” in Entanglement: Chinese and Russian Perspectives on Non-nuclear Weapons and Nuclear Risks, ed. James Acton (Washington, D.C.: Carnegie Endowment for International Peace, November 2017).
• 57James M. Acton, “Escalation through Entanglement: How the Vulnerability of Command-and-Control Systems Raises the Risks of an Inadvertent Nuclear War,” International Security 43 (1) (2018): 56–99.
• 58汪民乐 [Wang Minle], “弹道导弹突防对策综述” [Overview of ballistic missile penetration countermeasures]; 梁蕾 [Liang Lei], “洲际弹道导弹突防技术发展趋势” [Trends of ICBM penetration technologies development]; and 程强 [Cheng Qiang] and 游敬云 [You Jingyun], “对弹道导弹防御系统的电子对抗技术分析” [Analysis of electronic countermeasures against ballistic missile defense system].
• 59白新有 [Bai Xinyou], 王枭 [Wang Xiao]), and 楚樊星 [Chu Fanxing], “掩护弹道导弹突防支援干扰措施研究” [Research on support jamming measures for covering ballistic missile penetration].