Introduction

Table of Contents

The governments of China, Russia, and the United States all express support for arms control.¹ However, they disagree profoundly about its purposes and preconditions. At the root of this disagreement are important and growing differences between the threats that concern the United States and those that concern China and Russia. Having largely failed to bridge this divide, these states are now responding to their perceived threat environments in ways that drive nuclear arms racing and thus exacerbate interstate tensions. Should these tensions spill over into war, their responses could spark inadvertent escalation and nuclear use. Arms control could help to manage these risks and enhance the security of all three states—if they can find a mutually acceptable way forward.

The New Nuclear Arms Race

To date, the renewed U.S.-Russian nuclear arms race has been largely qualitative but could soon turn quantitative. One driver is an imbalance in conventional forces. Many of Russia’s neighbors, including Eastern European members of the North Atlantic Treaty Organization (NATO), are concerned about being coerced by Moscow through either nonmilitary or military means. Moreover, because of Russia’s conventional superiority around the Baltic region, Estonia, Latvia, and Lithuania also worry about a full-scale invasion. These concerns have led the United States to keep about 100 nonstrategic nuclear weapons (NSNWs)—out of a total of about 230 such weapons—deployed in Europe.² (In unhelpful language inherited from the Cold War, Russia and the United States generally use the term “strategic” to describe nuclear weapons with sufficient range to reach the other’s homeland from deployment locations in the possessor’s homeland or, in the case of sea-based weapons, from firing locations away from the other’s coast.³)

Russia, meanwhile, views itself as conventionally inferior to NATO across Europe as a whole. It relies heavily on nuclear weapons—especially NSNWs—for deterring large-scale aggression. The U.S. Department of Defense assesses that Russia has “up to 2,000” nonstrategic warheads and may be increasing that number.⁴ Moreover, Moscow is developing and deploying various new types of NSNWs, including, most controversially, the SSC-8—a dual-use ground-launched cruise missile that the United States assesses, almost certainly correctly, was developed in violation of the Intermediate-Range Nuclear Forces (INF) Treaty. (Dual-use weapons can accommodate a nuclear or nonnuclear warhead.)

Russia believes that the United States is seeking capabilities— particularly nonnuclear ones—to undermine its nuclear deterrent.

Washington believes that these developments reflect a growing Russian willingness to threaten to use, or even to use, nuclear weapons early in a conflict—particularly following an invasion of the Baltic states—in the hope of compelling the United States to stand down.⁵ Russian officials have strenuously denied that their nuclear doctrine embraces this concept, which is often called “escalate to de-escalate” in Western discourse.⁶ These denials have not assured Washington. Indeed, to correct the “mistaken Russian perception” that Moscow’s advantage in NSNWs would provide it with “a coercive advantage,” the United States has deployed low-yield warheads on some Trident D5 sea-launched ballistic missiles (SLBMs) and has started to acquire a nuclear-armed sea-launched cruise missile (SLCM), though the administration of U.S. President Joe Biden may cancel this program.⁷ Meanwhile, the United States’ withdrawal from the INF Treaty, ostensibly because of Russia’s deployment of the SSC-8 cruise missile, has opened the door to a competition in medium- and intermediate-range ground-launched missiles (though only Russian weapons are likely to be nuclear-capable).

The U.S.-Russian competition is also playing out with strategic weapons. Russia believes that the United States is seeking capabilities—particularly nonnuclear ones—to undermine its nuclear deterrent. Moscow fears that, after the further development and deployment of both offensive and defensive systems, the United States could be in a position to launch nuclear or nonnuclear preemptive strikes on Russia’s nuclear forces and then use ballistic missile defenses to mop up any surviving Russian weapons fired in retaliation. Stripped of its nuclear deterrent in this way, Moscow believes it would be left vulnerable to U.S. coercion.

Russia’s defense spending suggests that these concerns are acute. In 2018, for example, Russian President Vladimir Putin announced the development of three new kinds of “exotic” strategic nuclear delivery systems as a way of preserving Russia’s ability to defeat U.S. defenses.⁸ Russia has since deployed one of these systems—an intercontinental hypersonic glider, Avangard. The other two—a nuclear-powered cruise missile, Burevestnik, and a nuclear-powered torpedo, Poseidon—remain under development.

The New Strategic Arms Reduction Treaty (New START) helps to manage this competition by limiting all currently deployed U.S. and Russian strategic weapons, including Avangard. Following its extension in early 2021, this treaty will remain in force until 2026. However, the prospects for negotiating a follow-on agreement are unclear. Without a strategic arms limitation agreement in place, the result could be a renewed numerical arms race in strategic weapons.

China is not a party to New START or any other agreement that limits its nuclear forces. Currently, those forces are significantly smaller than either Russia’s or the United States’. The United States estimates that China’s nuclear warheads number in the “the low-200s.”⁹ By comparison, the United States has indicated that, as of September 2020, it possessed 3,750 nuclear warheads, while Russia has likely well in excess of 4,000.¹⁰ However, China is steadily expanding its nuclear arsenal without giving any indication of its intended endpoint. The U.S. Department of Defense expects China to “at least double” its warhead stockpile over the next decade.¹¹

Like Moscow, Beijing believes that the United States seeks to undermine its nuclear deterrent.¹² The commander of U.S. Northern Command, which is responsible for homeland defense, has publicly assessed that China is “investing heavily to improve the survivability and penetrability of its nuclear forces in an effort to guarantee its ability to retaliate following a strategic first strike.”¹³ To meet these objectives, Beijing is improving and expanding its long-range nuclear forces. Many of its programs are focused on ensuring that its nuclear forces will continue to have the ability to penetrate U.S. missile defenses for the indefinite future. Official U.S. sources, for example, have indicated that China has deployed intercontinental ballistic missiles (ICBMs) armed with multiple warheads and is “looking at” nuclear-powered cruise missiles and torpedoes.¹⁴ According to media reports, U.S. officials also believe that, in the summer of 2021, China conducted two tests of a novel nuclear-weapon delivery system that first enters orbit before releasing a hypersonic glider.¹⁵ To complicate any U.S. attempt to attack its nuclear forces preemptively, China is upgrading its mobile ground-based ICBM launchers, deploying six nuclear-powered ballistic missile submarines (SSBNs), and constructing at least 230 missile silos (and possibly many more), though it may not be intending to place an ICBM in every silo, at least initially.¹⁶ (Launchers are any device used to store and launch missiles. They include truck- and rail-based systems, silos, fixed above-ground systems, and launch tubes on submarines.)

Separately, China is also modernizing and expanding its force of regional missiles, including dual-use weapons.¹⁷ This development is probably motivated by the desire to acquire more credible options for limited nuclear use rather than concerns about force survivability.

Growing Escalation Dangers

In a deep crisis or a conventional conflict between the United States and China or Russia, the concerns about force vulnerability that drive arms racing could spark inadvertent escalation. Crisis instability is one potential danger.¹⁸ If the United States’ adversary concluded that a U.S. attack on its nuclear forces was imminent, it might issue nuclear threats or engage in limited nuclear use to try to terrify Washington into backing off. If the adversary were Russia, then in extreme circumstances, it might even attack U.S. nuclear forces preemptively to try to protect itself (China’s nuclear forces are currently too small to even attempt such an operation).

This risk of crisis instability is being exacerbated by the growing entanglement between the nuclear and nonnuclear domains.¹⁹ For much of the Cold War, threats to nuclear weapons came largely from other nuclear weapons. Today, both China and Russia perceive a real and growing danger of preemptive nonnuclear attacks on their nuclear forces—including with cyber capabilities, cruise missiles, and, in the future, hypersonic boost-glide missiles—and of interception after the launch of those forces by nonnuclear missile defense interceptors.

The United States, by contrast, is much less concerned about the survivability of its nuclear forces. Entanglement, however, is also undermining the survivability of nuclear command, control, communication, and intelligence (C3I) capabilities—including the United States’—and creating new escalation risks. For early-warning and long-range communications especially, the U.S. nuclear C3I system relies on a relatively small number of impossible-to-hide assets in space and on the ground. They are becoming increasingly vulnerable to the improving anti-satellite and long-range conventional strike capabilities being acquired by China and Russia. The U.S. nuclear C3I system is almost certainly vulnerable to cyber attacks too (though it is more difficult to assess whether the risk of successful attacks is increasing or decreasing).²⁰

To compound these vulnerabilities, many C3I assets—including ground-based radars and communication transmitters and early-warning and communication satellites—support both nuclear and nonnuclear operations. In a conventional conflict, an adversary might attack these assets to undermine the effectiveness of U.S. nonnuclear operations. However, such attacks could have the effect of degrading U.S. nuclear C3I systems. As a result, Washington might interpret them as the prelude to nuclear use and escalate the conflict in an attempt to coerce the adversary into backing down. In fact, the United States has explicitly threatened to resort to nuclear use should its nuclear C3I capabilities come under nonnuclear attack.²¹ (China and Russia are almost certainly concerned about the survivability of their nuclear C3I systems too. However, the extent to which China’s system, in particular, depends on dual-use assets is less clear.)

Unilateral efforts to enhance the resilience and survivability of states’ nuclear forces and their C3I systems can enhance security but typically involve trade-offs between different escalation risks. For example, China is currently developing a strategic early-warning system that could enable it to launch its nuclear forces before they were destroyed in an incoming attack.²² While a launch-under-attack capability could increase Beijing’s confidence in the survivability of its nuclear forces, it could also lead to China’s mischaracterizing, say, a U.S. missile test in the Pacific region as an attack—potentially catalyzing a nuclear response.

An Agenda for Cooperative Risk Reduction: Nine Practical Measures

Arms control offers a complementary, proven, and potentially powerful approach to managing the risks of both arms racing and inadvertent escalation and, more generally, to reducing the risk of conflict. The term “arms control” is used here in its broad, original sense to mean “all the forms of military cooperation between potential adversaries” intended to improve mutual security.²³ Such cooperation includes treaty-mandated limits on nuclear forces with intrusive verification and extends to confidence building, transparency, and behavioral norms.

A first step in reviving arms control is for Russia and the United States to commence negotiations toward a follow-on treaty to New START. Two authors of this report recently set out a detailed concept for such an agreement.²⁴ To avoid overloading negotiations and thus risking their collapse, the scope of a New START follow-on should be limited to strategic offensive arms, including new kinds of such weapons (nuclear and nonnuclear) developed since New START’s entry into force. Such an agreement would help mitigate the acute dangers created by Russia’s and the United States’ possessing large and uniquely destructive forces of strategic nuclear weapons that threaten one another.

A bilateral treaty on strategic offensive arms could not manage all the risks outlined above, however. Its focus on strategic arms would preclude any limitation of Russia’s and the United States’ NSNWs. And as a bilateral agreement, it would not regulate any Chinese capabilities and would also, therefore, be the wrong forum to manage the danger of misidentifying a missile test as an attack. Further, because its scope would be restricted to offensive arms, it would do nothing to address Chinese and Russian concerns about ballistic missile defense and not enough to manage threats to nuclear C3I capabilities.

In the near term, politically binding transparency and confidence-building measures present the most promising means to start addressing these lacunae, not least because of the difficulties posed by treaty ratification procedures within the United States. Such measures should be negotiated alongside a New START follow-on and would both complement and enable it. This report proposes six such measures:

• A U.S.-Russian data exchange for SLCMs and nonnuclear sea-launched boost-glide missiles (SLBGMs)
• A U.S.-Russian transparency regime for empty actual or suspected warhead storage facilities
• A U.S.-Russian confidence-building regime for European Aegis Ashore ballistic missile defense installations
• A U.S.-Chinese fissile material cutoff and transparency regime
• A trilateral launch notification agreement for ballistic missiles, missile defense tests, and space launches
• A trilateral agreement to establish keep-out zones around high-altitude satellites

Over the longer term, bilateral and trilateral treaties could be negotiated to provide a more durable and robust risk-reduction architecture. Three such agreements, with varying levels of ambition, are proposed here:

• A trilateral treaty to prohibit the development and deployment of space-based missile defenses
• A trilateral treaty to limit ground-based missile launchers, SLBM launchers, and bombers
• A U.S.-Russian limit on all nuclear warheads

Although these proposals vary significantly in their level of ambition, none likely present any currently insurmountable technical barriers—except the treaty to limit all warheads for which significant additional intragovernmental preparatory work would be required. Moreover, implementing any of them would help reduce nuclear dangers. Therefore, in laying out these proposals, we generally urge Beijing, Moscow, and Washington to adopt them. While calling for progress, however, we recognize that politics create real roadblocks, especially to the more ambitious proposals. The pace of progress on arms control will be constrained by the overall state of the U.S.-Russian and U.S.-Chinese relationships, and, to a lesser extent, the Russian-Chinese relationship. 

Cross-Cutting Implementation Issues

The proposals detailed here are intended to be practically useful for the officials who would be charged with negotiating them. While each proposal raises some unique difficulties, a few implementation challenges would be common to many of them. Determining a missile’s range, largely a technical issue, could be difficult (see appendix A). Exchanging data and facilitating inspections on the territory of U.S. allies—technically more straightforward—could be politically contentious.

Most arms control regimes require a dedicated mechanism to exchange data. Normal diplomatic channels may occasionally suffice, but they are ill-suited to rapid exchanges, especially involving large quantities of information. For this reason, Russia and the United States agreed, in 1987, to each set up a Nuclear Risk Reduction Center to enable reliable and rapid communications, including arms control notifications (the United States has since renamed its center the National and Nuclear Risk Reduction Center). These centers provide Russia and the United States with an already established, dedicated communication channel that would be useful in implementing virtually all the proposals described in this report.

But the proposals including China would also require data exchanges, and it is unclear whether Beijing has a similar center or organization. It may have one to facilitate its current participation in other arms control regimes. Perhaps the most relevant such regime is a 2009 Russian-Chinese launch notification agreement (discussed further in chapter 5) that requires the parties to maintain a communication channel. However, there is no publicly available information on what Chinese entity is responsible for sending and receiving notifications, thus making it difficult to assess this channel’s utility for other applications. Regardless, even if Beijing and Moscow have a dedicated communication channel suitable for exchanging arms control notifications, Beijing and Washington do not.

By agreeing to establish a communication channel, Beijing would be tacitly acknowledging the potential value of arms control and, in particular, of transparency—a step that it has not yet taken.

A U.S.-Chinese link and, if needed, an additional Russian-Chinese link would be useful in facilitating further cooperation both bilaterally and trilaterally. Although establishing the former channel would be straightforward from a technical perspective, the process would be plagued by politics. By agreeing to establish it, Beijing would be tacitly acknowledging the potential value of arms control and, in particular, of transparency—a step that, as discussed below, it has not yet taken.

Regarding inspections, a number of proposals would require them of specified kinds of U.S. military equipment located on the territory of its allies (and of any similar Chinese or Russian equipment deployed outside of their national territory in the future). While such inspections could be politically sensitive, the INF Treaty provides a clear precedent. Although it was negotiated bilaterally, this agreement permitted the Soviet Union and then Russia to conduct inspections at various bases in five NATO states. These inspections were facilitated through a separate agreement between the United States and those NATO states.²⁵ A similar approach, which would require close coordination between the United States and its allies, should be adopted here.²⁶

The Politics of Arms Control

U.S. priorities for arms control largely relate to China’s and Russia’s nuclear forces.²⁷ The Biden administration seeks to preserve the existing limits on Russia’s strategic forces and extend them to capture Moscow’s developmental exotic strategic nuclear weapons and its nonstrategic nuclear forces. Where China is concerned, the administration has identified risk reduction as its most immediate priority, while also seeking to prevent “unnecessary arms races”—which, in practice, means limiting the growth of China’s nuclear forces.²⁸ By contrast, China and Russia are primarily worried about developments in U.S. nonnuclear technology—precision strike capabilities and missile defenses, in particular—which those states fear could undermine the survivability of their nuclear forces.

As a result of this divergence, it is becoming ever more difficult to craft individual arms control proposals that simultaneously further all three states’ interests—at least as they define them—even if the obligations enshrined in each proposal are entirely reciprocal. Indeed, many of the proposals outlined in this report are intended to address the concerns of just one or two states.

It is becoming ever more difficult to craft individual arms control proposals that simultaneously further all three states’ interests— at least as they define them—even if the obligations enshrined in each proposal are entirely reciprocal.

One practical way to overcome this problem would be to negotiate over multiple proposals simultaneously. Even if no single measure were acceptable to all the parties concerned, a package deal, comprising two or more measures, could nonetheless be mutually beneficial. For example, Russia and the United States could agree to simultaneously implement one confidence-building measure focused on ballistic missile defense and another covering NSNWs. While such packages are suggested here, it is difficult to predict exactly which agreements may be within reach at any given time; therefore, success would depend on skillful diplomacy to take advantages of opportunities as they arise.

More generally, because of the potentially cataclysmic consequences of a nuclear war—which, because of radioactive fallout, climatic effects, and economic collapse, would be experienced by every state, including nonbelligerents—China, Russia, and the United States have a clear joint interest in avoiding inadvertent nuclear escalation, thereby creating much stronger shared interests than they often realize. Measures that reduced the likelihood of such escalation would create benefits for every participant, even if they did not address the concerns of every participant. In theory, this realization should leave Beijing, Moscow, and Washington more willing to address one another’s concerns—though, as a practical matter, they are likely to find the logic of negotiating package deals more compelling.

Another consideration for all three states—but particularly Russia and the United States—is their commitment, under Article VI of the Nuclear Non-Proliferation Treaty, “to pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament.” The proposals in this report would advance the goals of Article VI in various ways. Limits on fissile material production, warheads, and missiles are necessary steps toward a world without nuclear weapons, while inspections of storage facilities to verify the absence of nuclear warheads would be needed as part of any credible regime to verify the transition to such a world. In the meantime, many of these same proposals would help to curtail arms racing—as would enhanced transparency around ballistic missile defenses and sea-based missiles. Member states have also agreed that the purpose of Article VI can be advanced through “policies that could . . . lessen the danger of nuclear war.”²⁹ A number of proposals—including launch notifications and keep-out zones for high-altitude satellites—fall into this category. At a time when many non-nuclear-weapon states are deeply skeptical of the nuclear-weapon states’ willingness to live up to their disarmament commitments—and when there is little prospect of any major breakthrough in efforts to achieve a world without nuclear weapons—the proposals set out here offer a way to make visible progress on Article VI and thus bolster the nonproliferation regime.

Beyond the problem of finding enough shared interest to catalyze progress, China, Russia, and the United States also have their own specific concerns about arms control, even while they say they support it in principle. China is the most skeptical. It is not a party to any nuclear arms control agreement other than the 1968 Nuclear Non-Proliferation Treaty (though, like the United States, it has signed but not ratified the 1996 Comprehensive Nuclear-Test-Ban Treaty). Recently, Beijing has been very clear about its lack of interest in negotiations over nuclear limitations—at least until the United States makes deep reductions in its nuclear forces.³⁰ Beijing has failed, however, to indicate whether it believes that China’s security could be enhanced by other forms of arms control—though Chinese scholars have expressed a general concern that greater transparency would risk undermining the survivability of its nuclear forces.

China has previously participated in nonnuclear arms control with potentially hostile foreign powers when there have been clear benefits to doing so.

Yet the benefits and risks of transparency, as an abstract principle, are not at issue; the effects of specific proposals on Chinese security are. Indeed, China has previously participated in nonnuclear arms control with potentially hostile foreign powers when there have been clear benefits to doing so. For example, in the late 1990s, when Chinese-Russian relations were significantly worse than they are today, China negotiated a verified treaty that limits conventional weapons near its borders with Russia and three Central Asian republics.³¹ In that spirit, Chinese officials and analysts should consider what arms control measures related to nuclear weapons, missiles, and missile defenses would advance Chinese interests. They should then explore the trade-space with their U.S. counterparts—first in unofficial and then official dialogues—with the goal of developing mutually beneficial packages.³²

Russia and the United States, meanwhile, each have various concerns about engaging the other. In recent years, the United States has raised frequent and legitimate complaints about Russian compliance with various existing agreements and is therefore understandably hesitant to enter into new ones.³³ At the same time, Moscow points to the United States’ withdrawal from a number of arms control and nonproliferation agreements over the past two decades as a reason for skepticism about engaging Washington.³⁴ (Two of these withdrawals, from the 1972 Anti-Ballistic Missile Treaty and the 2015 Joint Comprehensive Plan of Action, were particularly damaging to U.S. credibility as Washington assessed that the Soviet Union and Iran, respectively, were complying with their commitments at the time it left the agreements.) Legally, abrogating obligations is certainly preferable to violating them; politically, however, Russian concerns about entering into new agreements with the United States also are understandable (and shared by other countries too). None of these concerns can be addressed through the text of an agreement, yet they have not precluded cooperation where it has been clearly mutually beneficial—as most recently illustrated by the extension of New START.

One question that Moscow and Washington will have to address is whether agreements should be politically or legally binding. The United States is generally supportive of the principle of politically binding transparency and confidence-building measures—not least because they obviate the challenge of obtaining the Senate’s advice and consent for treaty ratification—even if, in practice, Washington has sometimes shown a lack of willingness to elaborate or explore specific proposals. Russia, by contrast, often expresses skepticism about politically binding agreements, dismissing them as “verification for the sake of verification, transparency for the sake of transparency.”³⁵ It seeks the greater predictability that is supposed to come with legally binding agreements. Moreover, Russian officials privately argue that it is more politically difficult and time consuming for the United States to withdraw from treaties.³⁶

In June 2021, Russian Deputy Foreign Minister Sergey Ryabkov indicated a clear interest in negotiating legally and politically binding instruments alongside one another.

In practice, however, the benefits of treaties have not proven to be so marked. Given the fate of the Anti-Ballistic Missile Treaty, the INF Treaty, and the 1992 Open Skies Treaty, it is far from clear that a U.S. administration actually pays a greater political price for withdrawing from a treaty than from a politically binding agreement such as the Joint Comprehensive Plan of Action. And, although treaties contain withdrawal timelines, the minimum notification periods are often quite short—typically just six months.

Moreover, Russia has sometimes shown flexibility and, despite its concerns, has accepted politically binding agreements. For example, in 1988, the Soviet Union and the United States conducted the Joint Verification Experiment, in which each state measured the yield of a nuclear test conducted by the other, pursuant to a politically binding agreement. More recently, in June 2021, Russian Deputy Foreign Minister Sergey Ryabkov indicated a clear interest in negotiating legally and politically binding instruments alongside one another, stating that Russia and the United States could “decide to adopt a package of interrelated arrangements and/or agreements that might have different status if necessary.”³⁷

The hybrid approach advocated here—which starts with a treaty that constrains strategic offensive arms and is implemented alongside transparency and confidence-building measures—is consistent with Ryabkov’s suggestion and offers the most practical and plausible way forward. Politically binding measures currently represent the only viable way to address issues that, for technical or political reasons, cannot be managed through treaties. Moreover, historically, politically binding agreements have facilitated the development of legally binding ones. For example, the Joint Verification Experiment facilitated the 1974 Threshold Test Ban Treaty’s entry into force in 1990. In this spirit, the development of politically binding confidence-building measures should be the start of a process, not the end of one.

Notes

¹ Fu Cong, Statement at the General Debate of the First Committee, 74th Session of the United Nations General Assembly, New York, October 12, 2019, available at https://web.archive.org/web/20211023032402/https://www.fmprc.gov.cn/mfa_eng/wjb_663304/zzjg_663340/jks_665232/tyylb_665254/t1707314.shtml; Ministry of Foreign Affairs of the Russian Federation, “Russia’s Position at the Seventy-Fifth Session of the UN General Assembly,” July 23, 2020, https://www.mid.ru/en/web/guest/foreign_policy/international_safety/conflicts/-/asset_publisher/xIEMTQ3OvzcA/content/id/4252717; and Joseph R. Biden, Jr., “Interim National Security Strategic Guidance,” March 2021, 13, https://www.whitehouse.gov/wp-content/uploads/2021/03/NSC-1v2.pdf.

² Hans M. Kristensen and Matt Korda, “United States Nuclear Weapons, 2021,” Bulletin of the Atomic Scientists 77, no. 1 (2021): 44.

³ SLCMs are an exception (hence the qualifier “generally”) because, for practical reasons, they have never been accountable under “strategic” arms control treaties.

⁴ U.S. Department of Defense, “Nuclear Posture Review,” February 21, 2018, 9, 53, https://media.defense.gov/2018/Feb/02/2001872886/-1/-1/1/2018-NUCLEAR-POSTURE-REVIEW-FINAL-REPORT.PDF.

⁵ Ibid, 53–54.

⁶ “U.S. Claims on Russia’s ‘Escalation for De-escalation’ Doctrine Are Wrong—Envoy,” TASS, April 8, 2019, https://tass.com/politics/1052755.

⁷ U.S. Department of Defense, “Nuclear Posture Review,” 53.

⁸ Vladimir Putin, “Presidential Address to the Federal Assembly,” Moscow, March 1, 2018, http://en.kremlin.ru/events/president/news/56957. Putin also announced Kinzhal, an air-launched ballistic missile. So far, this system has been deployed only on MiG-31 aircraft and lacks the range to reach the United States. On managing the possibility that this weapon could be deployed on aircraft with longer ranges, see Pranay Vaddi and James M. Acton, “A ReSTART for U.S.-Russian Nuclear Arms Control: Enhancing Security Through Cooperation,” Carnegie Endowment for International Peace, October 2, 2020, 12–13, https://carnegieendowment.org/files/Acton_Vaddi_ReStart.pdf.

⁹ Office of the Secretary of Defense, “Military and Security Developments Involving the People’s Republic of China,” Annual Report to Congress, 2020, 85, https://media.defense.gov/2020/Sep/01/2002488689/-1/-1/1/2020-DOD-CHINA-MILITARY-POWER-REPORT-FINAL.PDF.

¹⁰ These figures exclude warheads awaiting dismantlement. U.S. Department of State, Bureau of Arms Control, Verification and Compliance, “Transparency in the U.S. Nuclear Weapons Stockpile,” fact sheet, October 5, 2021, https://www.state.gov/transparency-in-the-u-s-nuclear-weapons-stockpile/; and Hans M. Kristensen and Matt Korda, “Russian Nuclear Weapons, 2021,” Bulletin of the Atomic Scientists 77, no. 2 (2021): 91.

¹¹ Office of the Secretary of Defense, “Military and Security Developments Involving the People’s Republic of China,” 85.

¹² For a particularly nuanced and insightful analysis, see Tong Zhao, “Narrowing the U.S.-China Gap on Missile Defense: How to Help Forestall a Nuclear Arms Race,” Carnegie Endowment for International Peace, June 29, 2020, 11–29, https://carnegieendowment.org/files/Zhao_USChina_MissileDefense.pdf.

¹³ Terrence J. O’Shaughnessy, testimony before the U.S. Senate Armed Services Committee, February 13, 2020, 6, https://www.armed-services.senate.gov/imo/media/doc/OShaughnessy_02-13-20.pdf.

¹⁴ Office of the Secretary of Defense, “Military and Security Developments Involving the People’s Republic of China,” 56; and Jamey Keaten, “U.S. Envoy Warns China ‘Looking at’ New Nuclear Technologies,” July 8, 2021, https://apnews.com/article/europe-china-technology-government-and-politics-39029491f5863f10809dbbfc40862693.

¹⁵ Demetri Sevastopulo, “China Conducted Two Hypersonic Weapons Tests This Summer,” Financial Times, October 21, 2021, https://www.ft.com/content/ba0a3cde-719b-4040-93cb-a486e1f843fb. See also O’Shaughnessy, testimony before the U.S. Senate Armed Services Committee. It is unclear whether the glider mentioned by O’Shaughnessy is the same one described in the Financial Times report.

¹⁶ Office of the Secretary of Defense, “Military and Security Developments Involving the People’s Republic of China,” 45, 56; Joby Warrick, “China Is Building More Than 100 New Missile Silos in Its Western Desert, Analysts Say,” Washington Post, June 30, 2021, https://www.washingtonpost.com/national-security/china-nuclear-missile-silos/2021/06/30/0fa8debc-d9c2-11eb-bb9e-70fda8c37057_story.html; William J. Broad and David E. Sanger, “A 2nd New Nuclear Missile Base for China, and Many Questions About Strategy,” New York Times, July 26, 2021, https://www.nytimes.com/2021/07/26/us/politics/china-nuclear-weapons.html; and James M Acton, “Don’t Panic About China’s New Nuclear Capabilities,” Washington Post, July 27, 2021, https://www.washingtonpost.com/politics/2021/06/30/dont-panic-about-chinas-new-nuclear-capabilities/. A third Chinese silo field may also be under construction, see Rod Lee, “PLA Likely Begins Construction of an Intercontinental Ballistic Missile Silo Site Near Hanggin Banner,” Air University, August 12, 2021, https://www.airuniversity.af.edu/CASI/Display/Article/2729781/pla-likely-begins-construction-of-an-intercontinental-ballistic-missile-silo-si/.

¹⁷ Office of the Secretary of Defense, “Military and Security Developments Involving the People’s Republic of China,” 55–56.

¹⁸ See, for example, Caitlin Talmadge, “Would China Go Nuclear? Assessing the Risk of Chinese Nuclear Escalation in a Conventional War With the United States,” International Security 41, no. 4 (2017): 50–92.

¹⁹ James M. Acton, “Escalation Through Entanglement: How the Vulnerability of Command-and-Control Systems Raises the Risks of an Inadvertent Nuclear War,” International Security 43, no. 1 (2018): 56–99; and James M. Acton, ed., “Entanglement: Russian and Chinese Perspectives on Non-Nuclear Weapons and Nuclear Risks,” Carnegie Endowment for International Peace, November 8, 2017, https://carnegieendowment.org/files/Entanglement_interior_FNL.pdf.

²⁰ U.S. Department of Defense, Defense Science Board, “Task Force Report: Resilient Military Systems and the Advanced Cyber Threat,” Office of the Under Secretary of Defense for Acquisition, Technology and Logistics, January 2013, 6, https://nsarchive2.gwu.edu/NSAEBB/NSAEBB424/docs/Cyber-081.pdf.

²¹ U.S. Department of Defense, “Nuclear Posture Review,” 21.

²² Office of the Secretary of Defense, “Military and Security Developments Involving the People’s Republic of China,” 88–89.

²³ Thomas C. Schelling and Morton H. Halperin, Strategy and Arms Control (New York: Twentieth Century Fund, 1961), 2.

²⁴ Vaddi and Acton, “A ReSTART for U.S.-Russian Nuclear Arms Control.”

²⁵ The text of this agreement is available from the Office of the Assistant Secretary of Defense for Acquisition, “INF Treaty: Basing Countries Agreement,” https://www.acq.osd.mil/asda/ssipm/sdc/tc/inf/INF-Basing.html. Following the dissolution of the Soviet Union, the United States conducted inspections in Belarus, Kazakhstan, Russia, and Ukraine. Washington negotiated such inspection rights as necessary directly with the relevant governments. U.S. Department of State, Bureau of Arms Control, Verification and Compliance, “Treaty Between the United States of America and the Union of Soviet Socialist Republics on the Elimination of Their Intermediate-Range and Shorter-Range Missiles (INF Treaty),” https://2009-2017.state.gov/t/avc/trty/102360.htm.

²⁶ The 1990 Conventional Forces in Europe Treaty (to which individual NATO and Warsaw Pact members were signatories) provides a different model. However, this treaty limited equipment belonging to all parties—not just the United States and the Soviet Union—making it less relevant than the INF Treaty to the proposals in this report.

²⁷ Bonnie Jenkins, “Nuclear Arms Control: A New Era?,” Seventeenth Annual NATO Conference on WMD Arms Control, Disarmament, and Nonproliferation, Copenhagen, Denmark, September 6, 2021, https://www.state.gov/under-secretary-bonnie-jenkins-remarks-nuclear-arms-control-a-new-era/.

²⁸ Ibid.

²⁹ 2010 Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons, “Final Document,” NPT/CONF.2010/50 (Vol. I), New York, 2010, 21, https://www.nonproliferation.org/wp-content/uploads/2015/04/2010_fd_part_i.pdf.

³⁰ Ministry of Foreign Affairs of the People’s Republic of China, “Department of Arms Control and Disarmament Holds Briefing for International Arms Control and Disarmament Issues,” Beijing, July 8, 2020, available at https://web.archive.org/web/20211014015131/https://www.fmprc.gov.cn/mfa_eng/wjbxw/t1795979.shtml.

³¹ The 1997 Agreement on the Mutual Reduction of Military Forces in the Border Area.

³² For a detailed discussion of arms control proposals that would advance mutual security, see Tong Zhao, “Practical Ways to Promote U.S.-China Arms Control Cooperation,” Carnegie Endowment for International Peace, October 7, 2020, https://carnegietsinghua.org/2020/10/07/practical-ways-to-promote-u.s.-china-arms-control-cooperation-pub-82818.

³³ Examples abound in U.S. Department of State, “Adherence to and Compliance With Arms Control, Nonproliferation, and Disarmament Agreements and Commitments,” April 2021, https://www.state.gov/wp-content/uploads/2021/04/2021-Adherence-to-and-Compliance-With-Arms-Control-Nonproliferation-and-Disarmament-Agreements-and-Commitments.pdf.

³⁴ Ministry of Foreign Affairs of the Russian Federation, “Deputy Foreign Minister Sergey Ryabkov’s Interview With Kommersant,” December 19, 2018, https://www.mid.ru/en/foreign_policy/news/-/asset_publisher/cKNonkJE02Bw/content/id/3449525.

³⁵ “The USA Continues Previous Course, Which May Be Formulated Very Briefly: Russia Is a Geostrategic Enemy,” International Affairs, October 16, 2019, https://interaffairs.ru/news/show/24166 (in Russian).

³⁶ Personal communication, senior Russian official, July 2021.

³⁷ Italics added for emphasis. Sergey Ryabkov, “Keynote Address,” 2021 Carnegie International Nuclear Policy Conference, June 22, 2021, 5, https://ceipfiles.s3.amazonaws.com/pdf/Sergey+Ryabkov+Keynote_Transcript.pdf.