Toward Irreversibility in Nuclear Disarmament: The Role of Transparency Measures

ABSTRACT

Transparency can increase confidence in irreversibility in nuclear disarmament by enhancing verification and increasing the openness of fuel cycle choices and operations. This paper raises key verification challenges and describes how they can be addressed. Also, transparency measures could be utilized to ensure that current and future nuclear fuel cycle capabilities are used as intended and not as a means to breach irreversibility. Nuclear latency poses serious technical problems for irreversibility that may not be resolvable on a technical level. Political–legal approaches could be the best path forward in the future.

KEYWORDS:

• Nuclear weapon
• irreversibility
• transparency
• nuclear fuel cycle

Introduction

Although the prospects for deeper nuclear reductions and disarmament are difficult even to imagine in the current security environment, they reflect commitments undertaken by the nuclear weapon states recognized by the Treaty on the Nonproliferation of Nuclear Weapons (NPT). Thinking about future possibilities, in preparation for a time when further reductions may again be possible, highlights the issue of irreversibility, which complicates verification and presents serious technical challenges. To the extent it was considered in the past, it had largely been seen as increasing the time and cost involved in the reconstitution of weapons, ideally so that it is no less than what would be required to produce a new weapon. In past arms control, the political pledge not to cheat or to reverse the achievements of the agreement were subject to increasingly intrusive verification, at least up until the verification regimes negotiated in landmark treaties of the 1980s and 1990s. This understanding may have been acceptable at the high levels of weapons in the past, and may be acceptable at current force levels. However, if numbers decline further, it will look quite different, although technically, there may not be an alternative.

Nuclear weapons cannot be disinvented, and virtual or latent capabilities will, to some degree, continue to exist in a nuclear-free world and they will allow reductions and even disarmament, in principle, to be reversed. This reality of nuclear latency, seen through the prism of a disarmament debate, can offer a reduced risk of accidental or unauthorized use on the positive side as well as allow a high level of crisis instability and the prospect of disarmament being rapidly reversed.

Nuclear latency poses serious technical problems for irreversibility that may not be resolvable on a technical level. Political–legal approaches, if possible in conjunction with necessarily limited technical measures, could be the best path forward in the future. Transparency is canonically paired with verification and irreversibility, but it is a means of enhancing both (and to ensuring fuel cycle decisions are not used to reverse disarmament).

Transparency can increase confidence in irreversibility by enhancing verification and increasing the openness of fuel cycle choices and operations. It will be critical to achieving the greatest possible irreversibility. In support of verification, it will be important to fully coordinate transparency measures with verification regimes in order to address areas where the items or activities to be controlled were not readily dealt with by traditional verification approaches; to reduce costs, difficulties, and intrusiveness of monitoring compliance (Dunn and McFate 1992); and to further and more fully involve nonnuclear-weapon states in verification. For the fuel cycle, transparency will help ensure that fuel cycle decisions are sound and that capabilities are not being used to reverse progress on disarmament.

Civil society will inevitably play a role in increasing transparency; it is already doing so. However, this aspect of transparency is beyond the scope of this paper.

Enhancing Verification

As numbers decrease, ensuring that the reductions cannot easily be reversed becomes increasingly important. Verification will be at the forefront, but there are limits to verification. Verification of deeper cuts and disarmament will have to address deployed and non-deployed, strategic and nonstrategic, warheads, along with continuing attention to delivery systems. It would also need to address testing, facilities and latent capabilities from existing or shutdown nuclear weapons and existing nuclear energy programs, as well as material and weapon production and related capabilities. Verification would also be faced with unprecedented new requirements. Key challenges include:

• Material and warhead production and disposition baseline transparency/verification;

• Warhead storage and dismantlement transparency/verification;

• Material production, conversion and disposition transparency/verification; and

• Clandestine facilities/materials/weaponization detection/verification.

We believe we know how to address only some elements of these challenges today and some of those only marginally; the requirements will undoubtedly be more rigorous in the context of deeper cuts as well as disarmament, although the political-military conditions that could make this level of progress possible would presumably affect verification requirements at some time and to some degree.

Addressing the verification challenges that are unresolved today in joint endeavors provides increased intellectual, scientific and financial resources, as well as increasing transparency to the process, and should include:

• Developing a joint R&D program to resolve issues surrounding mutually acceptable warhead storage/dismantlement transparency building, as appropriate, on past work in a variety of for a, including International Partnership for Nuclear Disarmament verification (IPNDV) and the Quad; and

• Developing a joint R&D program to assess issues for further reductions in strategic forces involving the enhancement of future verification systems with transparency measures.

In addition to enhancing verification capabilities, additional transparency measures will be necessary to develop confidence that warheads and materials are fully accounted for, as well as for ensuring that old weapon capabilities will not be readily used to reverse disarmament, including:

• Declarations of historical warhead and fissile material production and current stockpiles with the highest degrees of accuracy and completeness possible, tied to verification and transparency measures needed for assessing their accuracy;

• Pledges not to reuse old or produce new material and warheads, and to dismantle old warheads, tied to verification measures;

• Once disarmament has been achieved, observed decommissioning, dismantlement or conversion of nuclear-weapon program sites;

• Ensuring access as appropriate to these activities by national technical means;

• Undertaking regular, reciprocal visits to declared former nuclear-weapon program sites (operational and closed), including weapon laboratories, production facilities, storage sites, test sites, etc., where visual observation and perhaps some types of limited measurements could be utilized to increase confidence in the accuracy of declarations; and

• Agreeing to provide detailed information on any other sites of concern, including, in limited cases, managed access to address concerns and increase confidence in its declarations.

The possibility of a “corral” for nonstrategic nuclear forces (NSNF) might be reconsidered prior to final disposition of these weapons and could be open to surveillance by national technical means and possibly site visits, despite its limits in terms of addressing the issues of numbers of NSNF held by the Russian Federation.

There may also be an opening for enhanced testing transparency. The Comprehensive Test Ban Treaty’s (CTBT’s) fate remains uncertain but as an interim measure, the moratorium on testing of the p-5 could be formalized by these states, declaring their intent to refrain from testing, perhaps backed up by reciprocated site visits by these states and other transparency provisions.

Ensuring Fuel Cycles Are Not Misused

In addition to using transparency measures to enhance verification, such measures could also be utilized to ensure that current and future nuclear fuel cycle capabilities are used as intended and not as a means to breach irreversibility. Of course, civil nuclear capabilities will likely not be proscribed and dismantled. There are real limits to such an approach, which can be illustrated by enumerating the steps that would be necessary if latency was to be substantially, but not wholly, reduced. It could require eliminating all peaceful uses of nuclear energy for power generation, or at least banning the production of weapon-usable fissile materials for any use whatsoever. It could also require unprecedented and ultimately unsuccessful efforts to monitor all individuals and organizations with weapon design or production knowledge, to ban or destroy relevant technologies and to restrict future R&D.

More realistically, nuclear capabilities could be managed in some fashion. Focusing on fissile materials, which are central to nuclear latency and irreversibility, an approach could include initiating or expanding efforts to limit or ban fissile material production for weapons, to limit the use of highly enriched uranium and plutonium in civil nuclear programs, to establish international spent fuel and plutonium storage regimes, to establish multinational or international nuclear fuel cycles (ownership and operation), to enhance transparency and accountability for relevant nuclear and dual-use exports, to further strengthen and universalize safeguards of the International Atomic Energy Agency and perhaps other options.

These and other such initiatives have been discussed for decades and have in most cases made only halting progress, including the fuel bank established in Kazakhstan. Future prospects do not appear particularly bright.¹ In any case, even if realized, this approach to managing nuclear latency would not come close to solving the problem and its impact on irreversibility. It does not comprise a “technical fix”. This approach does have the potential to mitigate key elements of the problem by increasing the time, costs and technical difficulty of reusing those materials or facilities and, if supplemented with transparency measures, it may constitute the only set of realistic and practical steps that can be pursued. In any case, transparency measures are needed to reduce uncertainties of fuel cycle choices and uses that could undermine irreversibility.

Having a better picture of states’ nuclear programs, which is a goal of the additional protocol, could help ensure that those programs will not be misused or used to reverse disarmament. Although fuel cycle choices that minimized the presence of direct-use materials would be a valuable step toward ensuring irreversibility, and should be pursued, transparency can be useful in any event, including:

• Assessing a state’s nuclear energy programs in terms of investment strategies, timing, scale and relationships to the state’s objectives and strategies (Sylvester 2019);

• Providing as appropriate complete information on all exports of nuclear and dual-use materials, facilities and technologies, including denied export license requests: and

• Applying universally comprehensive safeguard agreements and additional protocols, including updated lists and new authorities, following disarmament.

Directly relevant to irreversibility, the effective management, regionally and globally, of civilian, defense and excess defense nuclear materials worldwide to ensure safe, secure and transparent use of these materials from cradle to grave requires transparency measures. In addition to the declarations needed to baseline past fissile material production, whether produced for civil or military uses, there is a need to develop verification and transparency measures for fissile material, jointly if possible, including:

• Developing a joint R&D program to assess and if needed resolve issues surrounding transparency or verification of a fissile material cutoff, including measures that could be adopted without negotiation on a unilateral, reciprocal basis; and

• Conducting of a joint assessment of the bilateral plutonium management and disposition agreement, the Trilateral Initiative and Mayak transparency efforts to determine what elements could provide the basis for meaningful advances toward greater nuclear material transparency.

Other transparency measures could include:

• Enabling better information exchanges on fissile material declared excess to defense programs and its planned disposition, including its conversion to forms unattractive for use in nuclear weapons (due to the technical difficulty, cost and time required for its use again in weapons) and its planned use in civil nuclear programs, with confirmatory visits on the disposition of the material;

• Incorporating excess defense materials into the procedures and processes for materials management while expanding the perspective of organizations owning materials or involved with materials management to include transparency in an efficient and effective manner; and

• Providing assurances that specific material declared excess will not be returned to military explosive uses.

In this context, the international community should embrace and support transparency measures to provide confidence to all appropriate parties that the handling of nuclear materials meets global norms for safety, security and assurance of declared use. This would apply to production, storage, processing, transportation and ultimate disposition of these materials.

Efforts to promote best practices, with buy-in by industry and other stakeholders to ensure that facilities and activities throughout the world are indeed implementing these mechanisms are critical.

In addition, there may be opportunities for CTR-style contractual transparency as the United States and other states work to improve nuclear security throughout the world.

Conclusions

As noted above, none of the transparency measures proposed constitutes a technical fix to the problem of irreversibility. No such solution is available because in most cases it will be impossible to ensure that materials and facilities (even if converted) can never be used again in nuclear weapons. Moreover, perhaps none of the measures would be agreed today, in the current security environment. Even in a more favorable security environment, however, most would not be agreed unless we had reached a world in which disarmament was near realization or in fact realized. However, all should be considered and carefully evaluated in preparation for a time when progress again seems possible.

Author Note

The views expressed are the author’s own and not those of the Los Alamos National Laboratory, the National Nuclear Security Administration or the US Department of Energy.

Disclosure Statement

No potential conflict of interest was reported by the author.

Additional information

Notes on contributors

Joseph F. Pilat

Joseph F. Pilat is a Program Manager in the Center for National Security and International Studies at the Los Alamos National Laboratory and a Global Fellow at the Woodrow Wilson International Center for Scholars where he co-directs the Nonproliferation Forum. He served as Representative of the Secretary of Defense to the Fourth Review Conference of the Nuclear Non-Proliferation Treaty (NPT), and as senior adviser to the US Delegation at the 1995 NPT Review and Extension Conference. Dr Pilat also served as representative of the Secretary of Defense to the Open Skies negotiations. He has held positions in the Pentagon and the Congressional Research Service, and has taught at Cornell University, Georgetown University and the College of William and Mary. He is the co-editor of the Handbook of Nuclear Proliferation and Policy (Routledge, 2015), the co-author of The Politics of Weapons Inspections (Stanford University Press, 2017), the editor of The International Atomic Energy Agency: Historical reflections, Current Challenges and Future Prospects (Routledge, 2021), the editor of Nuclear Latency and Hedging: Concepts, History and Issues (Woodrow Wilson Press, 2019), the coauthor of The End of Arms Control? Challenges to Arms Control and Nonproliferation after the Russian Invasion of Ukraine (forthcoming).

Notes

¹ Similar approaches to other latent capabilities, including delivery vehicles, may be even more difficult. Whether they can be meaningfully developed and implemented is not at all clear.