January/February 2026
By Samantha Neakrase 

The four biennial Nuclear Security Summits, convening more than 50 heads of government between 2010 and 2016, delivered high-level attention on nuclear terrorism, drove concrete actions to prevent nuclear theft and sabotage, and strengthened the global nuclear security architecture. Yet momentum has waned amid competing priorities, worsened geopolitical dynamics, and weakened multilateral mechanisms. Hopes that new and existing institutions and initiatives would sustain momentum have proven difficult to realize.

Today’s persistent and evolving nuclear security risks—combined with an increasingly complex threat environment—demand renewed attention. Reversing the imbalance between nuclear risks and declining attention will require a more inclusive and flexible strategy that reflects many different priorities, elevates underrepresented voices, and builds new partnerships and coalitions. The 2027 Review Conference of the Amended Convention on the Physical Protection of Nuclear Material (A/CPPNM) and global expansion of nuclear energy offer near-term opportunities to regain focus but will require rethinking traditional approaches.

Summits Drive Progress

The summits drove major progress: Fifteen countries eliminated civilian stocks of weapons-usable nuclear materials, global inventories declined, and many countries strengthened regulations and facility security.¹ The summits also advanced best-practice sharing and peer review, and accelerated treaty ratifications, including by non-summit countries, leading to entry into force of the A/CPPNM, the only international agreement requiring physical protection of nuclear materials and facilities. The summits also produced 11 joint statements (“gift baskets”) in which participants committed to action on key issues such as transport security, minimizing stocks and use of highly enriched uranium (HEU), and insider threats, several of which were later formalized as International Atomic Energy Agency (IAEA) information circulars for wider adoption.²

After the final summit, states hoped that new mechanisms would sustain momentum and address emerging challenges. The summit action plans outlined how international organizations such as the IAEA could carry forward elements of the summits’ agenda. The Nuclear Security Contact Group was created to enable senior officials to continue driving progress without convening heads of government. The new series of IAEA international conferences on nuclear security (ICONS) in 2013, 2016, 2020, and 2024 were intended as regular venues for countries to highlight progress, make commitments, set priorities, and share expertise among practitioners. Following the final 2016 summit push to bring the A/CPPNM into force, countries envisioned periodic review conferences, triggered by the treaty’s entry into force, as a forum to monitor implementation, identify gaps, advance improvements, and address emerging threats.

Declining Attention to Nuclear Security

Although many countries continued improving nuclear security after the summits, the 2020 and 2023 editions of the Nuclear Threat Initiative’s Nuclear Security Index documented a marked decline in progress.³ For example, only two countries have eliminated their weapons-usable nuclear materials since 2016.⁴ Nuclear security has been overshadowed by other global crises and shifting priorities, including climate change and the COVID-19 pandemic. Russia’s 2022 full-scale invasion of Ukraine has further diverted global diplomatic attention and intensified divisions within the IAEA, contributing to increasingly difficult negotiations at recent agency general conferences.

New vehicles for dialogue such as the contact group and the IAEA ICONS showed early promise but have delivered mixed results. The contact group struggled to sustain consistent senior-level engagement and became dormant during the pandemic. The ICONS saw ministerial participation rise in 2020 but decline in 2024, when governments failed—for the first time—to agree on a ministerial declaration.⁵ Although a handful of countries have subscribed to nuclear security information circulars since 2016, most have stagnated.

An Evolving Threat Environment

It is imperative to maintain attention on nuclear security. Even after decades of effort to reduce risks, nuclear terrorism remains one of the greatest international security threats governments face. The risk environment is evolving, and nuclear security, the most effective tool to prevent catastrophe, requires continuous improvement through updated tools and best practices.

Nonstate threats have grown more complex: Beyond large terrorist networks, there is increased risk from self-radicalized individuals, domestic violent extremists, and insiders, who are more difficult to detect.⁶ Some extremists have targeted critical infrastructure, including nuclear facilities.⁷ Expanded access to drones, cyber tools, and advanced technologies such as AI introduce new nuclear security vulnerabilities.

Nuclear security standards and best practices now must also reflect the risks of nuclear facilities in conflict zones.⁸ Russia’s attacks on and occupation of Ukraine’s Zaporizhzhia Nuclear Power Plant violated laws and eroded norms against armed attacks on nuclear facilities.⁹ Attacks on Iranian nuclear facilities further weakened that norm and resulted in degraded nuclear security conditions.¹⁰

The expansion of nuclear energy is positive but poses new security challenges that must be addressed. As more countries pursue nuclear power to meet climate change and energy-security goals, many lack the regulatory frameworks and trained workforce needed to implement robust nuclear security, raising the risk that this expansion will outpace nuclear security preparedness. Small modular reactors and advanced reactors introduce unique security considerations tied to their designs, deployment models, and fuel types.11 Together, these trends underscore the need for renewed global attention on nuclear security at precisely the moment when political focus is waning.

Renewing Momentum

Despite declining high-level attention, there have been some bright spots. The 2022 A/CPPNM review conference adopted a substantive, forward-looking consensus outcome document outlining nuclear security priorities.12 Importantly, a majority of states-parties sent a request to the IAEA to convene a subsequent review conference, signaling support for continued dialogue on implementation of this foundational treaty.13

Although the 2024 ICONS did not produce a consensus ministerial declaration, the co-presidents’ statement gained support from more than 70 countries as reflected in information circular 1233.¹⁴ Two new nuclear security information circulars (1216 and 1217), which recognized the critical nexus between nuclear security and nuclear energy, were each endorsed by 25 or more countries.¹⁵

Three of the original nuclear security information circulars continue to drive engagement and tangible results. Belgium and the United States lead cooperation on insider threats under information circular 908, including at the Second International Symposium on Insider Threat Mitigation in March 2024 with participants from more than 50 countries.¹⁶ The United Kingdom advances transport security cooperation through information circular 909. Norway’s information circular 912 on HEU minimization has supported multiple symposiums, with a fourth planned for March 2026.¹⁷ Together, these efforts show sustained interest and demand for nuclear security cooperation.

Implementation and capacity-building efforts also continue through IAEA advisory services workshops, centers of excellence, and bilateral cooperation programs. Sustained funding for these activities will be essential as nuclear energy expands globally.

Together, these and other initiatives provide a solid foundation for future progress. They show continued willingness to engage constructively, the emergence of new tools and commitments, and sustained work by practitioners to strengthen security. The task ahead is to build on these efforts and bolster them with political and financial support.

Shaping a More Inclusive Narrative

Refocusing global attention on nuclear security requires a larger “nuclear security tent” to create space for more perspectives. Strong nuclear security depends on the engagement of all countries, not just those with weapons-usable nuclear materials or nuclear facilities. Nuclear security has long been framed mainly as a counterterrorism issue driven by those countries, a narrative that remains important but is too narrow, and one that sidelines countries whose priorities center on development, energy security, or peaceful uses.

A more inclusive narrative is needed, one that elevates a range of national and regional perspectives and connects nuclear security to broader priorities. Insights from NTI-hosted dialogues underscore the diversity of viewpoints and the need to respect regional identities. A one-size-fits-all approach is ineffective. Evidence shows that diverse decision-making improves innovation and financial performance.¹⁸ Global nuclear security is no different and will only be as strong as the diversity of countries shaping it. A narrative that reflects many perspectives will be more resilient, politically relevant, and sustainable over time.

Emphasizing Linkages Between Nuclear Security and Climate, Energy, and Development

Growing interest in nuclear power presents an opportunity for a broader nuclear security dialogue. Countries are turning to nuclear energy—including small modular reactors and advanced reactors—to meet net-zero carbon goals, strengthen energy security, and satisfy growing electricity demand. Nuclear technology also advances sustainable development through medical, agricultural, industrial, and infrastructure applications to improve lives around the world.

As more countries seek to adopt nuclear technologies for energy and development, it is critical to emphasize how nuclear security supports, rather than hinders, those goals. Strong nuclear security builds public confidence that nuclear technologies are safe, secure, and not vulnerable to misuse. That confidence is crucial for expanding and sustaining the benefits of peaceful nuclear technology. Concepts such as security by design, which integrate security into all stages of small modular reactor and advanced reactor design and development, will reduce later costs for operators and strengthen nuclear power’s growth. Newcomer countries can reinforce this by signaling to reactor vendors that nuclear security, as well as safeguards and spent fuel management, will be priorities as they review design options.

The link between nuclear power and nuclear security is reflected in recent multilateral statements. The “tripling pledge” approved at the 2023 UN Climate Change Conference (COP28) calls for nuclear expansion to meet “the highest standards of safety, sustainability, security, and non-proliferation” and commits support for countries pursuing new civil nuclear programs under those standards.¹⁹ Together with the two nuclear-energy-related information circulars at the 2024 ICONS, this explicit recognition of the nuclear power-nuclear security nexus provides a strong basis for continued dialogue on why robust security is essential to the successful and sustainable expansion of nuclear power. It reinforces a more inclusive narrative on nuclear security for all countries seeking the benefits of nuclear power.

These linkages should be explored further in international forums focused on climate change, nuclear power, development, and peaceful uses thereof—for example, COP, nuclear power ministerials, the World Economic Forum, and the nuclear Nonproliferation Treaty review process.

Informal and Regional Approaches

Consensus-based multilateralism has limits. In today’s polarized geopolitical environment, consensus alone is insufficient to drive progress, as we saw at recent IAEA general conferences and the 2024 ICONS. This does not mean abandoning consensus where it is achievable but supplementing it with more flexible approaches. Issue-specific coalitions, informal working groups, regional dialogues, and multi-stakeholder partnerships can advance progress when formal negotiations stall. The summit “gift basket” model demonstrated how like-minded countries can achieve outcomes outside consensus. Apart from the two new joint statements at the 2024 ICONS, this model remains underused. Similar approaches may be useful if consensus proves elusive at the 2027 A/CPPNM review conference and the 2028 ICONS.

Although the IAEA will remain central to global nuclear security, regional leadership must play a larger role in addressing the needs of an increasingly diverse nuclear landscape. Regional institutions and coalitions may offer more promising venues for open dialogue, particularly for countries feeling marginalized or disenfranchised in global settings where nuclear security can be perceived as an imposition or barrier to peaceful uses, or is overshadowed by complex political dynamics. Regional engagements can be more relevant to differing regional priorities, which are shaped by common values, history, and priorities. Regional risk assessment hubs could strengthen nuclear security cooperation and analysis. Subregional approaches can account for broader regional divisions around nonproliferation, disarmament, and other security issues.

Sustaining nuclear security over the long term will require strong regional leadership. Regional approaches offer more opportunities for regional leaders to emerge, enabling regions to shape agendas and negotiated outcomes at global meetings such as the 2027 A/CPPNM review conference and the 2028 ICONS. Encouraging greater regional ownership, empowering regional organizations, and ensuring that regional perspectives inform global processes should be core objectives in the coming decade. Platforms such as the African Commission on Nuclear Energy, the ASEAN Network of Regulatory Bodies on Atomic Energy, and the Organization of American States Inter-American Committee Against Terrorism offer promising foundations for these efforts.²⁰

Preparing for the 2027 A/CPPNM Conference

The most significant near-term opportunity to refocus political attention on nuclear security is the 2027 A/CPPNM review conference. As the only legally binding international agreement requiring the physical protection of nuclear materials and facilities, the amended convention remains foundational to the global nuclear security architecture. The 2027 review conference can serve both as a venue to assess progress and as a platform to renew political momentum.²¹

The 2022 A/CPPNM review conference showed that parties can work constructively even in a difficult geopolitical environment. Despite taking place shortly after Russia’s invasion of Ukraine, states-parties adopted a substantive and forward-looking outcome document by consensus.²² Building on that success, the 2027 review conference should aim to: promote the foundational role of the A/CPPNM; build a strong, effective, and sustainable convention regime; strengthen implementation, including Article 14; and encourage new commitments and universalization. In addition, it should strive to be inclusive of diverse perspectives; reaffirm the adequacy of the A/CPPNM; and agree on regular future review conferences as a vehicle for sustained nuclear security dialogue.²³

These objectives should inform the design of the preparatory process. With the 2022 precedent established, there is no need to revisit the rules of procedure or make significant adjustments to the agenda. Preparations can concentrate instead on substantive dialogue and negotiating the outcome document. Regional dialogues in 2026 could help shape priorities and coordinate positions ahead of negotiations.²⁴ States-parties should identify their priorities, consider ways to strengthen the outcome document, and plan how to demonstrate commitment through national statements or new joint statements among countries with shared interests. They should also begin building support for requesting that the IAEA host the next review conference. The most ambitious option would be to institutionalize regular review conferences, with each setting the date for the next one.²⁵

The 2027 review conference will not restore momentum by itself, but it can serve as a powerful anchor, especially if its outcomes feed into the 2028 ICONS. That conference, which is open to all IAEA member states and features more in-depth, cross-sector discussions, complements the review conference. Together, the two events offer critical opportunities to renew political attention.

Sustaining nuclear security will require rethinking global nuclear security dialogues. Regaining momentum amid competing crises and geopolitical tensions demands more flexible, inclusive, and regionally grounded approaches. This means broadening the nuclear security narrative; strengthening links to nuclear power and sustainable development; empowering regional leaders; and recognizing diverse priorities and perspectives. The 2027 A/CPPNM review conference and the 2028 ICONS are key moments to reinforce commitments and reset priorities.

A strong global nuclear security architecture will depend on diverse voices, shared ownership, and sustained attention. Progress is achievable, but only by reframing and adapting nuclear security to a changing world.

ENDNOTES

1. Samantha Neakrase, “The Global Nuclear Security Architecture: Closing Gaps to Build Greater Assurance, Accountability, and Action,” Nuclear Threat Initiative paper, September 2021, p. 1; Matthew Bunn, Nickolas Roth, and William H. Tobey, “Revitalizing Nuclear Security in an Era of Uncertainty,” Belfer Center for Science and International Affairs report, January 2019, pp. 1-4, 15-18, 70.

2. Sara Z. Kutchesfahani, Kelsey Davenport, and Erin Connolly,“The Nuclear Security Summits: An Overview of State Actions to Curb Nuclear Terrorism 2010–2016,” an Arms Control Association and Fissile Materials Working Group report, July 2018.

3. “NTI Nuclear Security Index: Losing Focus in a Disordered World,” Nuclear Threat Initiative, July 2020, p. 8; “NTI Nuclear Security Index: Falling Short in a Dangerous World,” Nuclear Threat Initiative, July 2023, pp. 5-6.

4. Neakrase, Global Nuclear Security Architecture, p. 19; NTI, Nuclear Security Index 2020, p. 39.

5. Information on ministerial attendance at ICONS 2020 and 2024 appears in IAEA General Conference reports: IAEA, “International Conference on Nuclear Security: Sustaining and Strengthening Efforts,” August 31, 2020, p. 1; IAEA, “International Conference on Nuclear Security: Shaping the Future,” p. 1.

6. Rebecca L. Earnhardt, Brendan Hyatt, and Nickolas Roth, “A Threat to Confront: Far-Right Extremists and Nuclear Terrorism,” Bulletin of the Atomic Scientists, January 14, 2021; Sneha Nair, Anna Pluff, and Christina McAllister, “The Threat from Within: An Overview of the Domestic Violent Extremist Threat Facing US Nuclear Security Practitioners,” Stimson Center, November 2, 2023.

7. Dan Sullivan, “National Guard ‘neo-Nazi’ aimed to hit Miami nuclear plant, roommate says,” Tampa Bay Times, June 13, 2017.

8. Nickolas Roth, Ross Matzkin-Bridger, and Jessica Bufford, “Nuclear Facilities in Times of Crisis,” Nuclear Threat Initiative, May 2024, p. 1.

9. Ibid., pp. 1, 5, 9.

10. Theft of nuclear materials was a major concern in the aftermath of the strikes. Reports indicated that Iran had moved its roughly 400 kilograms of HEU before the attacks, raising alarms because weapons-usable nuclear material is more vulnerable during conflict and transport, and a new location might lack the protections of the damaged facilities. Insider threats could also be a risk, as individuals with access to the material could be susceptible to bribes. See Edward Helmore, “JD Vance suggests Iran’s uranium stockpile is still intact despite US strikes,” The Guardian, June 24, 2025.

11. World Institute for Nuclear Security, “Security of Advanced Reactors,” August 2020, pp. 26-28, 32; Laura Holgate, “Sustaining Attention on the Security of Nuclear Materials and Facilities: Challenges and Strategies in a Shifting Global Landscape,” NTI Global Dialogue discussion paper, July 2025, pp. 2, 6.

12. IAEA, “2022 Conference of the Parties to the Amendment to the Convention on the Physical Protection of Nuclear Material,” outcome document, April 2022.

13. IAEA, “Communication Dated 24 March 2022 received from the Permanent Mission of the United States of America concerning a Joint Proposal to the IAEA to convene further CPPNM as amended Review Conferences,” March 25, 2022.

14. IAEA, “Communication dated 23 July 2024 received from the Co-Chairs for the preparatory process of the Ministerial Declaration for the 2024 International Conference on Nuclear Security (ICONS) concerning the Statement by the Co-Presidents of the International Conference on Nuclear Security 2024: Shaping the Future, 20-24 May 2024,” July 24, 2024.

15. IAEA, “Joint Statement on Advanced Nuclear Energy Technologies,” June 4, 2024; IAEA, “Joint Statement on the Role of Nuclear Security in Harnessing the Power of Nuclear Energy,” June 4, 2024.

16. “INFCIRC/908: Insider Threat Mitigation,” Insider Threat Mitigation Hub.

17. IAEA, “The Fourth International Symposium on HEU Minimization organized by the Norwegian Radiation and Nuclear Safety Authority (DSA) (organized in cooperation with the IAEA).”

18. Vivian Hunt, Dennis Layton, and Sara Prince, “Why diversity matters,” McKinsey & Company, January 2015, pp. 1-2.

19. At COP28, countries launch “Declaration to Cripple Nuclear Energy,” U.S. Department of Energy, 2023.

20. For ideas on potential regional forums for dialogue, see Irma Arguello, Trevor Findlay, and Hubert Foy, papers prepared for the November 2019 NTI Global Dialogue.

21. Jonathan Herbach and Samantha Pitts-Kiefer, “More Work to Do: A Pathway for Future Progress on Strengthening Nuclear Security,” Arms Control Today, October 2015.

22. Ibid.

23. Samantha Neakrase, “A Roadmap to the 2027 A/CPPNM Review Conference,” Nuclear Threat Initiative, July 2025.

24. NTI and the IAEA hosted regional dialogues in advance of the 2022 Review Conference; similar NTI-led workshops are now underway.

25. Samantha Neakrase, “Strengthening Nuclear Security With a Sustainable CPPNM Regime,” Arms Control Today, June 2019.

January/February 2026
By Sverre Lodgaard and Alexander Nikitin

During the 60 years between 1960 and 2020, some 69 arms control agreements were negotiated and signed in an attempt to limit or otherwise manage the world’s most destructive weapons. Despite their value, by the late 1970s, some of the agreements and treaties began to be suspended, violated, deconstructed, or parties withdrew from them. That process intensified in the 2010s and 2020s, sparking rumors of the death of arms control. Nevertheless, dozens of agreements are still in force, and although some of the paradigms under which they can be understood have faded, this does not mean the disappearance of arms control as a political phenomenon. In the current and any future security system, arms control is a necessary component.

This article, co-authored by one Western and one Russian expert, analyzes 69 arms control agreements and organizes arms control history into six paradigms, which are deconstructed into basic principles and reconstructed as rising and falling curves reflecting world-order changes.

Arms control is aimed at limiting, prohibiting, or eliminating certain types of weapons, as well as framing the geopolitical, military, and technical capabilities of states aiming at preventing or limiting armed conflict. It has proven to be a relatively systemic political process of interaction among states and alliances in formats of information exchange, talks and negotiations, elaboration, conclusion, verification, and implementation of agreements and treaties.

Paradigm theory supposes that international relations are shaped not only by material factors, but also by clusters of ideas, concepts, and visions affecting politics through social interaction. Mostly, the clusters are shaped by themselves and “live” within the political consciousness and political behavior of national elites and international organizations. Thus, similar to paradigms in science, they are tied to certain political communities and historic conditions and rise, shape, dominate, and dissolve over time. States rarely openly negotiate paradigms in a “rational choice” manner; rather, paradigms result de facto from negotiation practices, manifesting and surviving only in a certain political and international atmosphere, such as while certain world-order models prevail.

The distribution of arms control agreements by decade shows that there were two peaks in achieving new agreements and treaties: in the 1970s (18 new agreements) and in the 1990s (24 new agreements), followed by a decrease to four new agreements in the 2010s and zero in the 2020s.

Breaking the arms control universe into paradigms reveals what has become outmoded, what has been rendered irrelevant under current circumstances, what is useful but in need of updating, and what remains relevant and called for. This process also makes it possible to assess if, and to what extent, the paradigms depend on each other. For instance, although in theory stabilization can be achieved through rearmament, in practice it only has been achieved in a disarmament context.

Despite the difficult geopolitical environment, there are options for pursuing another round of U.S.-Russia strategic arms control negotiations, incorporating lessons learned so far. In the global setting, any arms control approach must address military landscapes that are multipolar and multidomain and characterized by rapid technological turnover.

Attempts to analytically cluster arms control agreements have been undertaken by different experts, most notably by Jozef Goldblat and Jayantha Dhanapala.¹ This article identifies six arms control paradigms based upon sets of interconnected principles that are specified for each paradigm.

The Risk-Reduction Paradigm

This paradigm covers agreements (see Table 1) aimed at lowering the risk of military incident and escalation to war. Agreements in this cluster aim to facilitate instant communication between political and military authorities, define “rules of the road” in military-to-military interactions, and institutionalize military-technical cooperation.

The paradigm is based on three principles beginning with capabilities for instant communication. The first arms control agreement was triggered by the 1962 Cuban missile crisis. The need for instant communication to avoid war by accident or misunderstanding led to the 1963 Hotline Agreement. Another agreement to reduce the risk of accidental nuclear war was signed in 1972, followed by similar agreements between France, the Soviet Union and the United Kingdom a few years later.

Second is the principle of setting rules of the road for military movements and operations. The 1972 Incidents at Sea Agreement between the United States and the Soviet Union was adopted to prevent incidents on and over the high seas.² Navy-to-navy cooperation worked well. In 1975, the two countries agreed on rules of behavior to avoid escalation to nuclear war and, in 1989, rules for that purpose were extended to apply to all armed forces in the Dangerous Military Activities Agreement.

The third principle involved institutionalizing security cooperation. The first agreement of this kind was concluded in 1987, when the Soviet Union and the United States established nuclear risk reduction centers to supplement the hotline and the customary diplomatic channels. In 2000, they agreed to establish a joint data exchange center for data from early warning systems and notification of missile launches, but this center remained only partially operational.

The hotline has been used during military crises such as the Arab-Israeli wars of 1967 and 1973, the 1971 war between India and Pakistan, the Soviet intervention in Afghanistan in 1979, the September 11 terrorist attacks, the U.S. invasion of Iraq in 2003, and in connection with alleged Russian hacking ahead of the 2016 U.S. presidential election.

Among the rules-of-the-road agreements, the Incidents at Sea Agreement stands out as particularly useful even though it does not apply to submerged submarines because of their inherently covert nature. U.S. and Soviet/Russian submarines have collided several times.

The nuclear risk reduction centers of 1987 became the vehicle for all agreed missile notifications between Moscow and Washington, as well as the exchange of information pertaining to arms control agreements. The centers remain operational. Another institutionalized arms control mechanism—the Conflict Prevention Centre of the Conference on Security and Cooperation in Europe, based in Vienna—was established to support confidence- and security-building measures and facilitate conciliation of disputes, but it suffered from an imprecise mandate and, in recent years, from the deterioration of great-power relations.

None of the risk-reduction agreements have been canceled, as of now. Some have been upgraded but others have not, and compliance has been eroding, so there are big question marks about the relevance and utility of many of them under rapidly changing conditions.

The Nonproliferation Paradigm

The nonproliferation paradigm covers bans on the proliferation of weapons of mass destruction (WMDs) and other weapons and military activities to states and nonstate actors, as well as to international territories and the global commons (viz., the high seas, Antarctica, the atmosphere, or outer space).

The paradigm refers to an early group of international agreements, treaties, and conventions, the crowning achievement being the nuclear Nonproliferation Treaty (NPT) signed in 1968 (Table 2). Geographical prohibitions include the spread of military activities to Antarctica and to the moon, nuclear weapons to outer space, and nuclear tests in water, in the atmosphere, or on land. A series of treaties on nuclear-weapon-free zones (NWFZs) later extended this line to cover practically all of the Southern Hemisphere and some parts of the Northern Hemisphere.

This paradigm is also based on three principles, beginning with prohibiting WMD proliferation to the global commons and areas under special international jurisdiction. For instance, the Seabed Treaty of 1971 prohibits the emplacement of WMDs on the ocean floor and in its subsoil. The Outer Space Treaty banned WMD orbiting around Earth, and the Moon Treaty prohibited bringing and locating WMDs on Earth’s satellite. The Antarctic Treaty of 1959 established an international regime to regulate scientific activities, protect the environment, and avert territorial conflicts in the region. The arms control provisions—determining that the region shall be used exclusively for peaceful purposes—derive from those objectives.

The second principle, preventing WMD proliferation to more states, centers on the NPT, which became the backbone of a comprehensive regime of national, regional, and multilateral nonproliferation measures. Agreements and treaties on nuclear-weapon-free zones (NWFZs) are more comprehensive realizations of the same principle.

The third principle, preventing WMD proliferation to nonstate actors, is reflected in the 1980 Convention on the Physical Protection of Nuclear Materials, which went into force in 1987 and seeks to prevent such materials from falling into the hands of terrorist organizations. In 2005, an amendment was adopted, expanding the application of control measures from international transport to include nuclear facilities and nuclear material in peaceful domestic use, storage, and transport.

Two out of four agreements concluded in the first decade of arms control, namely the Seabed and the Outer Space Treaties, were of little or no military significance, but the others left a lasting impact. The 1967 Treaty of Tlatelolco became the forerunner for a series of regional NWFZs, and the NPT became the backbone of an increasingly comprehensive regime of nonproliferation measures.

The number of nonproliferation initiatives grew significantly in the 1990s; 11 agreements were reached between 1992 and 1997. Their significance is corroborated by their contents. Belarus, Kazakhstan, and Ukraine acceded to the NPT as non-nuclear-weapon states; the NPT was extended indefinitely; new NWFZ agreements were concluded for Southeast Asia and Africa; the Comprehensive Test Ban Treaty (CTBT) was signed; and the International Atomic Energy Agency (IAEA) introduced the Model Additional Safeguards Protocol. Finally, South Africa reverted to non-nuclear-weapon state status and joined the NPT on its own initiative.

The Limitation Paradigm

The limitation paradigm covers quantitative ceilings on the future expansion of arsenals and differs from agreements that physically cut quantities or eliminate entire classes of existing weapons. This paradigm includes initial information exchanges on accumulated military capabilities—mostly, but not exclusively, quantitative—and ceilings on the further development and accumulation of assets. The Strategic Arms Limitation Talks and resulting agreements were based on this logic. SALT I limited launchers, whereas SALT II set ceilings primarily on deployed launchers and delivery vehicles, excluding stored and reserve weapons.³

A new principle is the freedom to mix. SALT I allowed the parties to increase their submarine-based forces in return for an equivalent decrease in their land-based ones. All subsequent agreements ending with the 2010 New Strategic Arms Reduction Treaty (New START) have applied variations of this principle.

The most important principle is parity. By freezing different force structures at existing levels, SALT I did not provide for quantitative parity, but SALT II did so, establishing an equal basis for limitations and future reductions.

Finally, this paradigm included the principle of limiting specific military activities. Very importantly, nuclear weapons testing was successively reduced and outlawed by the partial, threshold, and comprehensive test ban treaties.

Limitation was the paradigm of the 1970s. The SALT I limitations lasted for little more than five years. SALT II was tailored to existing expansion plans and easily adhered to but it was never ratified. U.S. President Ronald Reagan declared it void in 1986. The anti-ballistic missile (ABM) limitations eroded in the late 1980s and 1990s and ended in 2002. The limitations on nuclear weapon tests were replaced first by national moratoria and then by the CTBT in 1996.

Together with the ABM Treaty, SALT planted the seeds of strategic arms control. When the Cold War ended, the process was resumed and overtaken by substantial disarmament agreements with intrusive verification provisions. What remains from this category are agreements limiting specific activities: The Nuclear Supplier Group, the Missile Technology Control Regime, the Australia Group, and the Wassenaar Arrangement on export control of conventional arms and dual-use technologies.

The paradigm was short lived for obvious international political reasons. First, increased tensions between East and West in the 1980s brought arms control to a standstill. Then, in the 1990s, the end of the Cold War opened the gates for real disarmament, meaning physical elimination of parts of existing arsenals.

The Stabilization Paradigm

The stabilization paradigm covers agreements to promote strategic stability and crisis prevention by slowing the arms race and promoting disarmament. Early attempts to enhance strategic stability were made in the 1970s when the ABM agreement was concluded. A few years later, another wave of intensified East-West conflict interrupted these efforts, which resumed when the Cold War ended. In a joint statement preceding the Strategic Arms Reduction Treaty I (START I), the Soviet Union and the United States defined the objectives: “To ensure strategic stability, transparency and predictability through further stabilizing reductions … seeking agreements that improve survivability, reduce incentives for a nuclear first strike and implement an appropriate relationship between strategic offenses and defenses.”⁴

This paradigm was based on three principles, starting with preserving strategic stability. Strategic offensive and defensive arms should be configured so that neither side’s defenses could undermine the other side’s retaliatory strike capability. “Preserving mutual deterrence” is shorthand for this concept. The ABM Treaty and the process of de-MIRVing—the reduction of multiple independently targetable reentry vehicles—on ICBMs set in motion by START I were important steps in this direction.

Another principle of this paradigm is reducing incentives for a nuclear-armed state to be the first to use military force of any type in times of crises, otherwise labeled crisis stability. The 1991 Conventional Forces in Europe (CFE) Treaty had a distinct non-offensive profile. The 1987 Intermediate-Range Nuclear Forces (INF) Treaty eliminated an entire class of weapons that were unnerving and destabilizing because of their high accuracy and short flight times.

Reducing incentives to acquire new or more weapons out of fear that the opponent would gain a meaningful advantage, strengthening stability by curbing the arms race, is the third principle. Such incentives were alleviated by arms control and disarmament agreements and in many cases were adjusted by compensatory national measures in order to secure ratification.

When the first arms control agreements were concluded, the parties were not ready to act on any broader understanding of arms control. The idea of joint efforts to enhance the stability of force constellations took more years to mature. It had to be communicated, discussed, and finessed into common understandings. The SALT series of talks began in 1969 not because Soviet and U.S. strategic cultures and political goals were converging, but because arms control made it possible for them to simultaneously promote their irreconcilable interests and their common interests in stabilizing nuclear deterrence to avoid nuclear war. The ABM Treaty, prohibiting nationwide ballistic missile defense, was understood to be a fundamental prerequisite for stable deterrence. In the 1980s, things went from bad to worse when Reagan introduced his Strategic Defense Initiative.⁵

START I brought strategic stability back on target. The number of warheads carried by each strategic missile, known as multiple independently targetable reentry vehicles (MIRVs), was reduced. On the Soviet side, increased mobile ground- and rail-basing was permitted, and deployment of survivable ballistic missile submarines was encouraged on both sides. START II, often referred to as the “de-MIRVing agreement” but never ratified, would have been a major contribution to strategic stability, as well; its most outstanding feature was the reduction of all MIRVed ICBMs.

De-MIRVing thus was set in motion, albeit slowly and halfheartedly. The United States removed the last MIRVs from its land-based missiles in 2014, but kept them on submarine-launched ballistic missiles (SLBMs); survivable submarines are not under the same pressure of early use as land missiles. Russia, meanwhile, maintains limited numbers of MIRVs on both ICBMs and SLBMs.

In the field of conventional forces, the CFE and CFE-1A agreements and subsequent adaptations were another victory for stability and disarmament. The declared objective was to eliminate the disparities in conventional forces that were detrimental to stability. This was achieved by deep and verifiable cuts of offensive weapons.

Mechanisms for the regular exchange of information, verification, and compliance also contributed to confidence-building between former adversaries. But in 2000s, former Warsaw Pact members and former Soviet republics started to join NATO and refused to sign an adapted CFE. Then in 2007, Russia suspended participation in the treaty and, in 2015, ended participation in the treaty’s Joint Consultative Commission.

The Disarmament Paradigm

Different from the principles of limitation, the disarmament paradigm requires the decommissioning, disassembling, and physical destruction of agreed-upon quantities or entire classes of existing weapons and carriers, some of which had been capped at a previous stage. The entire START process from the early 1990s to the 2020s belongs to this category. It cut Russian and U.S. inventories, first from more than 11,000 to about 6,000 accountable warheads, then to 1,550 deployed warheads and 700 delivery vehicles on each side.

The most comprehensive application of the disarmament paradigm may have been the elaboration and adoption of the Chemical Weapons Convention (CWC), requiring full and complete elimination of chemical weapons from the planet. Although the Biological and Toxin Weapons Convention (BTWC) belongs to the same cluster, the lack of verification mechanisms in that treaty significantly reduces the value of that prohibition. Other landmark achievements were the Intermediate-Range Nuclear Forces Treaty, the CFE Treaty, and the presidential nuclear initiatives (see Table 5).

The principles of the disarmament paradigm include the elimination of entire classes of weapons. The 1987 INF Treaty was the first agreement to do this, followed by the CWC in 1993, the Anti-Personnel Landmines Convention in 1997, and the Cluster Munitions Convention in 2008.

The next principle is the elimination of or cuts to delivery vehicles and “accountable” warheads. The START reductions are based on launchers and the means of delivery, establishing counting rules for warheads. The 2002 Strategic Offensive Reductions Treaty (SORT) dealt exclusively with warheads but had no verification provisions and left the reserves untouched.

Another principle is mandating the follow-on destruction of units to be withdrawn. The INF Treaty demanded to destroy all missiles except the guidance systems and the warheads, which were returned to stockpiles for possible reuse. Under START I, decisions on removing weapons from accountability were based on the destruction of launchers or their conversion to carry permitted missiles. New START had similar provisions, but removed missiles need not be destroyed, and bombers could be converted to conventional missions.

Finally, this paradigm included the reduction of reserve arsenals of nondeployed launchers, setting in New START a combined overall limit for deployed and undeployed launchers (800 units, of which up to 700 could be deployed).

Clearly, this was the disarmament decade in arms control history. START I was a big step ahead for nuclear disarmament, in terms of its arms reductions and its comprehensive exchange of information and intrusive verification provisions. The unratified START II aimed to cut the arsenals by another 50 percent from 6,000 “accountable” warheads on each side to between 3,000 and 3,500. START I remained in force until New START succeeded it. Building on START I, New START is known for its reductions, comprehensive information exchange, and intrusive verification provisions that were suspended in times of the Ukrainian crisis.

The 1987 INF agreement eliminated all Soviet and U.S. land-based intermediate-range missiles. Table 5 lists nine disarmament agreements concluded in the 1990s, starting with the comprehensive CFE agreement and including disarmament majors such as the START I, presidential nuclear initiatives, and CWC treaties.

In 2017, a novelty was introduced. Born in protest over the failure of nuclear-weapon states to live up to their disarmament obligations, the treaty for the Prohibition of Nuclear Weapons (TPNW) renounced nuclear deterrence and required that its member states abstain from any involvement in nuclear weapon planning whatsoever. The nuclear-weapon states and their allies opposed this treaty’s creation and ratification and ignored it.

The Confidence-Building Paradigm

The confidence-building paradigm was born during negotiations for the 1975 Helsinki Final Act. The measures were made militarily significant by the Stockholm Conference 10 years later and further enhanced by the Vienna documents. Other important parts of the paradigm are the U.S.-Soviet Nuclear Risk Reduction Centers and the Open Skies Treaty (Table 6).

The risk-reduction and confidence-building agreements may be seen on a continuum stretching from instant crisis management to long-term trust generation. Confidence-building measures were premised on the assumption that no party harbored any intention to change the status quo by military means. This was commonly believed to be the case in Europe in the 1980s but not today. In that sense, confidence-building measures are “good weather” measures, whereas risk-reduction agreements address conflict situations of immediate concern.

The four principles underlying this paradigm start with the exchange of information and observation missions that were required by these agreements and greatly improved the transparency of military deployments and activities.

The next principle promoting predictability, typified by the Stockholm Conference which turned the Helsinki confidence-building measures into an elaborate set of militarily significant measures, widening the scope of information exchange, defining longer prior notification times for large military exercises, and enhancing inspection rights.

Third is the principle of providing security assurances as manifested in the 1994 Budapest Agreement, whereby Russia, the United Kingdom, and the United States extended security assurances to Ukraine and national security assurances to non-nuclear-weapon states summarized in UN Security Council Resolution 984 of 1995.

The final principle is institutionalizing confidence-building measures by establishing structures, such as the Nuclear Risk Reduction Centers (1988), the Vienna Conflict Prevention Center (1991), and the U.S.-Russia Joint Data Exchange Center for early warning systems and notifications of missiles launches (2000).

The Helsinki Final Act, which proclaimed the recognition of existing borders and of different political and economic systems in Europe, established the political framework for confidence-building measures.

When the Stockholm Conference convened, the 1986 arsenal of confidence and security building measures became a watershed achievement: They were, in effect, the beginning of the end of the Cold War. The Vienna Documents of 1990, 1992, 1999, and 2011 later adapted and upgraded these measures. Since then, however, confidence and security building measures have not kept pace with the rapid political and military changes and have lost much of their relevance.

The Erosion of Arms Control

Only eight treaties and conventions were concluded in the 21st century. Among them the SORT (or “Moscow Treaty,” 2002); International Convention for the Suppression of Acts of Terrorism (2005); Cluster Munitions Convention (2008); Central Asia NWFZ (2009); New Start (2010); the Joint Comprehensive Plan of Action (JCPOA) with Iran (2015); and the TPNW (2017). This slowdown is reinforced by the fact that many important agreements have been terminated (see Table 7).

A New Arms Control Paradigm

Arms control paradigms had different fortunes and influence (see Figure 1).

The limitation paradigm is outmoded. In a multipolar world of asymmetrical force postures and multidomain war strategies, parity in select categories of weapons is a straitjacket, launchers are inadequate units of account, and verification by national technical means is not enough to allay suspicions of noncompliance. Moreover, some types of weapons call for radical solutions rather than mere ceilings at existing levels. Sometimes, a total prohibition is easier to verify than reductions.

The conditions for revitalizing the confidence-building paradigm—understood as long-term systemic measures to enhance the transparency and predictability of security relations—are not present either. Globally, such measures do not square easily with big power rivalry and controversial spheres-of-interest policies.

The risk-reduction paradigm tries to come to grips with immediate dangers by instant communication to avoid accidents and by rules of the road to prevent escalation. In a transitioning world replete with serious conflicts, this paradigm has fundamentally important tasks. Assuming that all the big powers want to avoid another world war, a nuclear war in particular, risk-reduction measures are a sine qua non.

The survival of the nonproliferation paradigm rests with the legitimacy of the NPT and the extension of the nonproliferation principle to more states. The five internationally recognized nuclear-weapon states are united in support of the treaty but have failed miserably to live up to their disarmament obligations. The treaty and the international regime connected to it have proven resilient, but betrayed on the disarmament dimension, stuck in the Middle East, and mostly irrelevant to the Asian nuclear-weapons states, the question is whether they will remain intact.⁶

One important nonproliferation track remains stalled: efforts to ensure the nonproliferation of weapons to more environments, especially to outer space. Another track has been underused: More can be done to prevent the proliferation of WMDs and related technologies to nongovernmental actors. Governments tend to be united against nongovernmental competitors. What is required therefore is attentiveness, diligence, and timely initiatives, including overcoming political opposition.

The disarmament paradigm, however, remains relevant. In the current U.S.-Russia dyad, new long-range nuclear and conventional weapons can be fitted under the principles of common ceilings and freedom to mix that were applied under New START. Reduction of reserve arsenals and the destruction of decommissioned units also can be accomplished by proven arms-control methods.

The disarmament and stabilization paradigms are intertwined. Stability was the number one objective of arms control from the beginning. Next was damage limitation should war occur, followed by reduction of the costs of military preparations. Disarmament was desirable but subordinated to stability. However, the history of arms control shows that stability has been achieved by prohibitions (the ABM treaties) and reductions (the START process) and undermined by arms buildup, suggesting that disarmament should be upgraded on the list of arms control objectives.

Thus, agreements that survived and are still valid mostly belong to three of six historic paradigms: risk reduction (10 agreements, all are still alive); nonproliferation (27 agreements, 3 out of order); confidence-building (13 out of 19 agreements are alive). The disarmament paradigm (limitations with real cuts) has been significantly damaged by withdrawals and paralysis(10 out of 19 agreements do not work anymore).

Judging from the history of dying and surviving agreements, it is likely that the next stages of arms control would concentrate on principles of risk reduction, confidence building, and de-escalation techniques, rather than on physical elimination or capping of weapons systems. Separate negotiating tracks may be envisaged for different clusters of weapons. Some tracks could remain bilateral, and some could be multilateral;⁷ some tracks would move slower than others, and some might remain stuck for decades.

Instead of a simplistic request to involve in talks all new carrier systems (U.S. B-21 bombers, Sentinel ICBMs, and Columbia submarines along with Russian Sarmat ICBMs, Oreshnik hypersonic intermediate-range missile, Avantguard boost-glide missile, Kinzhal hypersonic missile, and Poseidon submarines), a relatively new principle could be of system-for-system trade-offs, not numerical ceilings. One side may express readiness not to finalize or not to deploy some of those systems, if the other side would agree to negotiations and make its own comparable (though not necessarily symmetrical) concessions.

The principle of “free mix between categories” or “overall ceiling” was applied within New Start to strategic carriers; each side was allowed to mix freely any quantities of ICBMs, SLBMs and strategic bombers. A new approach could be to apply the free-mix principle to strategic and nonstrategic carriers within an extended overall ceiling. Russia or the United States may want to add to the arsenal new short- or midrange missiles, as they already do. Under such an approach each side could expand their midrange arsenal, in exchange for cutting some of strategic items.

If U.S.-Russia relations improve, then within the contours of future arms control, there could be a return to exchange of data on missile activities. If any country resumes nuclear testing, then an exchange of data on forthcoming or past nuclear tests may become a subject of mutual interest or agreement, either via the Comprehensive Test Ban Treaty Organization, or bilaterally, and lead to revitalizing the data exchange centers established in 1987.

Cyberweapons, artificial intelligence, and new technologies also need to be discussed to identify the risks and advantages they bring.

To reopen space for arms control and disarmament, the world powers must step back from security policies based on zero-sum thinking and worst-case analyses. Above all, there must be a return to cooperative security in some form. To prepare for that possibility, leaders should ensure that the arms control toolbox is updated and prepared for application.

Arms control is grounded in the realization that lasting security is something states must build together with their adversaries or counterparts for mutual gain. To bring it back to life and make proper use of its potential, the world must revert to cooperative security in some form or other. For that to happen, communication across political divides must be encouraged, and leaders must be willing to talk with one another in a businesslike way.

ENDNOTES

1. Jozef Goldblat, Arms Control: A Guide to Negotiations and Agreements, SAGE, 1994, p. 800; Jayantha Dhanapala, “The Hierarchy of Arms Control and Disarmament Treaties,” Denver Journal of International Law & Policy, Vol. 19, No. 1 (2000), p. 5.

2. Later, 11 NATO countries—Canada, France, Germany, Greece, Italy, the Netherlands, Norway, Portugal, Spain, Turkey, and the United Kingdom—concluded bilateral agreements with Russia modeled on the U.S.-Soviet Agreement to Prevent Incidents at Sea.

3. The Strategic Arms Limitation Treaty series of agreements did not limit reserves; such a limitation became a feature in the Strategic Arms Reduction Treaty series of agreements.

4. “Soviet-United States Joint Statement on Future Negotiations on Nuclear and Space Arms and Further Enhancing Strategic Stability,” June 1, 1990.

5. Jeffrey Lewis, “The Nuclear Option: Slowing the New Arms Race Means Compromising on Missile Defenses,” Foreign Affairs, February 22, 2021.

6. See: Joelien Pretorius and Tom Sauer, “Ditch the NPT,” Survival, Vol. 63, No. 4 (2021), pp. 103-24.

7. Ulrich Kühn (ed.), Alexey Arbatov, David Santoro and Tong Zhao, “Trilateral Arms Control? Perspectives from Washington, Moscow, and Beijing,” Institute for Peace Research and Security Policy Research Report #002, 2020.