New START: Sustaining the Future of Strategic Stability

Photo by Dan Meyers on Unsplash

By Manseok Lee and Austin Mullen

The United States and Russia currently have 6,372 and 5,800 nuclear weapons, respectively. Following the termination of the Intermediate-Range Nuclear Forces (INF) Treaty in 2019, the only treaty remaining that constrains these numbers is the New Strategic Arms Reduction Treaty (New START). Provisions of the treaty have been implemented smoothly, yet, the treaty regime is facing imminent collapse. The United States and Russia face several issues related to the scope and utility of the New START, and the disagreements concerning these issues are taking place not only between the United States and Russia but also within the United States itself. If the New START lapses in February 2021, it will be a ‘global security crisis’ as there will be no strategic arms control arrangements remaining on the world’s two largest nuclear arsenals. In this short article, we would like to introduce the consequences and reasons for the probable collapse of the New START and the principles the U.S. administration should follow to maintain arms control between the two nuclear superpowers. We argue that the future of New START needs to be separated from other issues, such as the inclusion of China, because a ‘one size fits all’ approach is untenable.

Source: Hans M. Kristensen and Matt Korda, “Status of World Nuclear Forces,” Federation of American Scientists, April, 2020.

A World without the New START

Arms control refers to international restrictions upon the development, deployment, and usage of certain weapons systems, which affects peace and security in three ways. First, arms control discloses information about military power through verification activities and thus enhances transparency about intentions and capability. Therefore, it has the effect of increasing the predictability of the other party’s behaviors and preventing misjudgment. Second, by imposing restrictions on military buildup and deployment, it has the effect of alleviating and preventing an arms race. Finally, by presenting examples of arms reduction through negotiations to allies and third countries, it has the effect of inducing long-term cooperation rather than short-term competition.

The end of the New START, therefore, is likely to adversely affect the strategic stability of both parties. Without the transparency provided by the New START’s verification regime, the United States and Russia will have to resort to making assumptions on the other’s capabilities and intentions, which could increase the chance of a miscalculation with regard to the operation of their own strategic forces. Furthermore, without restrictions on the buildup and deployment of nuclear forces, the United States and/or Russia may want to expand their strategic nuclear capabilities. One side’s nuclear arms buildup could bring about a security crisis in which both sides jump into a nuclear arms race. In addition, the United States and Russia’s nuclear arms buildup is likely to lead China to build up its own nuclear forces. If the United States and Russia fail to comply with their obligations to reduce nuclear weapons as stipulated in Article 6 of the Nuclear Nonproliferation Treaty (NPT), which orders that nuclear weapons states will make good faith efforts towards disarmament, other members of the NPT who do not possess nuclear weapons will gradually lose motivation to comply with international nonproliferation norms. This would destabilize both international and regional security and could thus result in increased security costs for both the United States and Russia. Therefore, the United States and Russia should, at the bare minimum, maintain the strategic nuclear arms control framework. The prospects, however, are not so bright.

Challenges to the U.S.-Russia Nuclear Arms Control

According to its terms, the New START will remain in effect until February 2021, although it can be extended by up to five years by consent of both parties. Here, we explore the four issues that may affect the extension or termination of the New START.

China is not included

As Marshall Billingslea, President Trump’s new special envoy for arms control, commented in a recent interview with the Washington Times, “One main failing of New START is that it does not include the Chinese.” China’s participation would increase transparency, predictability, and stability, though Beijing is reluctant to participate due to its smaller nuclear arsenal (300 warheads compared to 6,000 for the United States and Russia). One of the reasons for China’s reluctance to participate in the nuclear arms control with the United States and Russia is that if China participates, their nuclear systems will be subject to inspection and monitoring. This is very burdensome for China, which has not disclosed the actual capabilities of its nuclear forces. There is also a significant inequality in the size of nuclear forces between China and the other two nuclear superpowers, so China would likely have to accept unfavorable conditions in the negotiation with the United States and Russia. If China wants to participate in the nuclear arms control talks on an equal footing, it must increase its nuclear arsenal along with the modernization of its nuclear weapons. However, it is not an optimal choice for China as international pressure on transparency could increase as China acquires more nuclear weapons. Therefore, China is unlikely to participate in the nuclear arms control talks. 

Limits on new weapons and non-strategic nuclear weapons

Both the United States and Russia are accelerating their development of advanced nuclear weapons. At the center of such efforts are hypersonic glide vehicles, which can fly at least five times faster than the speed of sound; nuclear-powered cruise missiles; nuclear torpedoes; and cutting-edge non-strategic nuclear weapons. So long as a reliable nuclear triad exists in U.S. and Russian nuclear forces, these new weapons will not fundamentally alter the workings of bilateral deterrence. Thus, theoretically, arms control of these weapons should be possible. However, incorporating these new weapons into strategic arms control would be difficult for three key reasons. First, as Rose Gottemoeller, the former chief negotiator of the New START, points out, “these exotic systems have more of a political function than a security one,” which means that their role is to signal scientific and military prowess and to enhance national prestige. Thus, the two parties may not want to impose excessive restrictions on such weapons. Second, as technological development is currently underway, neither side will easily agree about their effects on strategic balance. Third, robust inspections could be difficult, as neither side wants to provide information about the technology it is currently developing. Therefore, arms control of these new weapons would only be possible after the development of the technology has become more visible. When it comes to non-strategic nuclear weapons, the concerns of NATO allies should also be considered – as they were in 1979 when the Soviet Union deployed its SS-20 intermediate-range missiles. Concerns about Russia’s new nuclear weapons among Poland and the Baltic states are particularly high. These concerns may be alleviated through development of U.S. nonstrategic weapons systems, or by adequate arms control limiting Russian deployment of non-strategic systems. Moscow would want concessions in exchange for such a limit, most likely focusing on the historically-maligned U.S. missile defense systems in Europe. 

Solid verification procedures

Marshall Billingslea also stated that “The Obama administration negotiated a very weak verification regime. It really has very little of what the original START treaty [Strategic Arms Reduction Treaty] contained and has significant loopholes in the way verification is physically conducted, which the Russians have been exploiting.” A concern for adequate verification is understandable. However, the New START did not require the same verification as the START to ensure compliance, as rules for counting nuclear warheads changed.  Furthermore, intrusive verification is not always a positive. Excessive verification increases security costs and provides an incentive to avoid verification. If the avoidance of verification is detected, it could severely damage mutual confidence. Therefore, the design of a verification regime should be tailored to the weapon systems subject to arms control. If the U.S. negotiating team demands a high level of verification apart from the arms control clause, the burden of verification is likely to make it difficult to reach a deal.

Nuclear modernization programs

Russia is in the process of a major modernization of its nuclear forces, while the United States has been accelerating its own modernization program. The Russian military is currently modernizing its submarine and missile fleets. Meanwhile, the United States plans to update every leg of its triad. Such modernizations of nuclear forces should not have a significant impact on mutual deterrence in the near future. Even if nuclear forces are modernized, the structure of the nuclear triad will not change significantly. But consensus on which side will gain a strategic advantage when the modernization is completed may vary. This is important because in past arms control talks, the party with higher-quality nuclear weapons led negotiations with an advantage. Therefore, apart from mutual deterrence, the nuclear modernization programs in the two sides could be a factor that makes it difficult to conclude negotiations on nuclear disarmament.

What should be done?

If the New START lapses in February 2021, there will be no nuclear arms control arrangements in place between the United States and Russia for the first time since 1972. Such an outcome could adversely affect both strategic stability and the international nonproliferation regime. Therefore, the United States and Russia should, at the very least, agree to extend the New START or to replace it with a treaty containing similar provisions. We argue that the United States and Russia should separate the future of the New START from other issues, such as the inclusion of China, because a “one size fits all” approach to arms control is untenable. 

In an effort to ensure that bilateral nuclear arms control is maintained, we conclude the article by offering four recommendations to the United States administration. First, nuclear arms control talks with China should proceed separately from talks concerning the New START. China has shown no interest in nuclear arms control negotiations unless and until the United States and Russian nuclear forces are in rough numerical parity with China (from thousands to hundreds). This is not realistic, so the United States should focus more on establishing regional arms control more amenable to Beijing. In this way, a form of parity may be achieved that is acceptable to both China and the United States. Second, advanced weapons systems, in the near term, will not affect the current strategic landscape – arms control on these systems should not be a priority. The United States should, however, seek to address Russia’s non-strategic arsenal in order to alleviate the security concerns of its NATO allies, though progress will likely come at the cost of U.S. missile defenses in Europe. Third, an unconditionally robust verification regime increases both operating and security costs. Therefore, the United States should promote the tailored verification of weapons systems subject to arms control and, further, should conduct research into detection techniques in an effort to confirm the ability of new nuclear weapons. Fourth, to prevent the appearance of the United States conceding nuclear superiority to Russia, modernizations should be allowed to proceed as planned, so long as the parties comply with the limitations of the New START and ensure transparency in terms of the performance of the nuclear weapons.

Manseok Lee is a third-year Ph.D. student at the UC Berkeley Goldman School of Public Policy.

Austin Mullen is a third-year Ph.D. student in Nuclear Engineering at UC Berkeley and the deputy director of Nuclear Policy Working Group.

The views expressed in this article do not necessarily represent those of the Berkeley Public Policy Journal, the Goldman School of Public Policy, or UC Berkeley.


1. Hans M. Kristensen and Matt Korda, “Status of World Nuclear Forces,” Federation of American Scientists,
April, 2020,
2. Hans M. Kristensen, “A Decade After Signing, New START Treaty Is Working,” Federation of American
Scientists, April 8, 2020,
3. Bill Gertz, “Envoy says China is key to new arms deal with Russia,” Washington Times, May 7, 2020,
4. Arms Control Association, “Nuclear Weapons: Who Has What at a Glance,” last modified July 2019,
5. Alan Cummings, “Hypersonic Weapons: Tactical Uses and Strategic Goals,” War on the Rocks, November
12, 2019,
6. Rose Gottemoeller, “The New START Verification Regime: How Good Is It?” Bulletin of the Atomic
Scientist, May 21, 2020,
7. Rose Gottemoeller, “Russia Is Updating Their Nuclear Weapons: What Does That Mean for the Rest of
Us?” Carnegie Endowment for International Peace, January 29, 2020,
8. Gertz, “Envoy says China is key to new arms deal with Russia.”
9. Anatoli S. Diakov, Daryl G. Kimball, and Steven Pifer, “New START Treaty,” Deep Cuts Issue Brief 7
(2018), 3.
10. Congressional Research Service “U.S. Strategic Nuclear Forces: Background, Developments, and Issues,”
April 27, 2020,