Toward Nuclear Disarmament Building up Transparency and Verifcation Malte Göttsche and alexander Glaser (editors) Toward Nuclear Disarmament Building up Transparency and Verifcation Malte Göttsche and alexander Glaser (editors) Content 2 Foreword 4 Ambassador Rüdiger Bohn Executive Summary 8 1. Baseline Declarations 14 Mona Dreicer 1.a Appendix: Secure Declarations 26 Sébastien Philippe 2. Monitoring Regimes for All-Warhead Agreements 34 Alexander Glaser 3. Fissile Material Stocks and Production 54 Sharon Squassoni and Malte Göttsche 4. Nuclear Monitoring and Verifcation Without Onsite Access 86 Alexander Glaser and Irmgard Niemeyer 5. Weapons Production and Research 116 Moritz Kütt 6. Conclusion: Building up Transparency and Verifcation 140 Malte Göttsche and Alexander Glaser Authors 150 3 Foreword Foreword aMbassador rüdiGer bohn 4 Foreword Transparency and compliance mechanisms of future disarmament agreements are necessary to create a positive momentum in a strained international arms control and disarmament environment. Especially in the absence of tangible progress on the issue of comprehensive reductions of nuclear arsenals, in- termediate steps such as limitations on fssile material production (FMCT) or nuclear testing (CTBT) as well as progress on risk reduction are of paramount signifcance. Rapid technological progress in the development of new weapons systems that are still largely unregulated (Artifcial Intelligence, Lethal Autono- mous Weapons Systems, Space Weapons, Hypersonics) present new challenges to arms control and disarmament and have potential destabilizing effects. Given these challenges, it is all the more important – in light of the 50th anni- versary of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and with a view on the upcoming NPT Review Conference – to send a positive sig- nal for the preservation of the nuclear order, to build bridges between Nuclear Weapon States and Non-Nuclear Weapon States, and to work out concrete mea- sures and reach progress for a step-by-step approach to nuclear disarmament. The feld of Nuclear Disarmament Verifcation is particularly appropri- ate for this purpose. It can help to prepare the ground and foster politi- cal approximation on more general issues regarding future nuclear arms control and reductions. Henry Kissinger and Sam Nunn aptly summed up the importance of Nuclear Disarmament Verifcation in a joint article for the New York Times in 2007: “A world without nuclear weapons will not simply look like today’s world minus nuclear weapons, but in such a world there must be a sustainable and resilient mechanism of cooperative security including a robust verifcation system”. Preparatory work for such a mechanism must begin now. To achieve signifcant reductions in nuclear arsenals in the future, the development and practical testing of verifcation procedures and arrangements are essential. Conceptual and methodological issues as well as technical aspects must be taken into ac- count. Such work serves our political interest in demonstrating that no unsur- mountable hurdles exist for credible multilateral nuclear disarmament, and in providing a platform for the notion that the future of nuclear arms control and disarmament is multilateral. 5 Foreword Any new efforts and initiatives in the feld of Nuclear Disarmament Verifcation could draw on knowledge and expertise gained through the implementation of former and current bilateral and multilateral treaties and regimes. The same ap- plies to a number of recent initiatives including the “International Partnership for Nuclear Disarmament Verifcation”, the German-French “NuDiVe” exercise, the “Quad Initiative” (Norway, Sweden, United Kingdom, United States) and last but not least the “United Nations Group of Governmental Experts on Nuclear Disarmament Verifcation”. Over years, the Government of the Federal Republic of Germany has been strongly involved in the conceptual and practical development of different aspects of Nuclear Disarmament Verifcation. This report illustrates these continuous efforts. It presents fresh ideas and new approaches of several renowned scholars and will – we hope – serve as a meaningful and timely contribution to the important debate on how to advance nuclear arms control in the years to come. Ambassador Rüdiger Bohn, Deputy Federal Government Commissioner for Disarmament and Arms Control, Federal Foreign Offce 6 Foreword 7 executive Summary Executive Summary 8 executive Summary Despite or precisely because of the current crisis of nuclear arms control, it is pressing to sketch potential pathways on how to get back on a track of reduc- tions in weapon arsenals, eventually making progress towards disarmament. As a requirement for such a process to succeed and be sustainable, having effective and widely accepted verifcation tools available is crucial. Technical studies on how to verify nuclear disarmament have been published for over two decades. Among the most notable ones are a study by the U.S. National Academy of Sciences’ Committee on International Security and Arms Control, 1 a report by the International Panel on Fissile Materials, 2 and several books. 3 The Nuclear Threat Initiative convened an international expert group, 4 and several bilateral and multilateral initiatives have contributed to the debate, in particular the Trilateral Initiative 5 and the U.K.-Norway Initiative. 6 Current multilateral fora include the Quad Nuclear Verifcation Partnership 7 and the International Partnership for Nuclear Disarmament Verifcation. 8 With this report, we pursue two goals. First, we seek to build upon the previous work to provide an overview of what we consider likely to be the technical main elements of disarmament verifcation. By examining the current state- of-the-art of verifcation technology, we identify those areas where verifcation technologies and concepts are readily available – thus providing an update to prior studies – and areas where gaps need to be addressed both by further scientifc research and preparatory measures by governments. Verifcation at low warhead numbers will likely be comprehensive and rigorous. Progress toward nuclear disarmament should be diffcult to reverse. Corre- sponding monitoring arrangements can be expected to become more compre- hensive the smaller arsenals become. While current research – such as work on warhead confrmation measurements using information barriers – focuses on these long-term challenges, it is equally important to think about what kind of measures would be required and could be implemented as next steps. Therefore, the second goal of this report is to highlight the spectrum of mon- itoring and transparency options: comprehensive and complex verifcation measures are at the long-term end; on the other end are much simpler non-in- trusive steps that could be pursued in the shorter term given political will. Such initiatives could but do not have to be legally binding. They would contribute to confdence-building and lay the basis for further measures along the way. Notably, in 2019, the Group of Governmental Experts on nuclear disarmament 9 executive Summary verifcation concluded that “confdence-building measures may complement nuclear disarmament verifcation arrangements between the implementing parties of a specifc treaty.” 9 The objective of monitoring is to confrm declared activities and to confrm with high confdence the absence of undeclared facilities, stocks, and activi- ties. The starting point of verifcation regimes is for a state to issue a baseline declaration, covering those elements limited by an agreement. In the chapter Baseline Declarations, Mona Dreicer examines how such declarations would ft into the larger disarmament framework. She proposes that narrow and unver- ifable declarations could be issued initially as part or even independent of an agreement to begin a confdence-building process, with states increasing the level of detail once they are ready to do so. In an appendix, Sebastien Philippe offers a related technology-based approach, where states could provide de- tailed declarations in a secure manner upfront, but only reveal their content to inspectors gradually as required by the agreement and as confdence in the process increases over time. Verifcation of arms-control agreements that place limits on all weapons in the stockpiles are likely to face some fundamentally new challenges and may require new verifcation approaches. In the chapter Monitoring Regimes for All-Warhead Agreements, Alexander Glaser proposes three types of monitoring regimes that could be used to verify such agreements: the absence regime, the limited-access regime, and the confrmation regime. These regimes can build on each other. Only the third phase would require actual warhead measure- ments, but it may well be that parties will consider a regime without such measurements adequate for deep cuts in the nuclear arsenals. In their chapter Fissile Material Stocks and Production, Sharon Squassoni and Malte Göttsche fnd that the current IAEA safeguards toolbox will be insuff- cient for verifcation in weapon states. Signifcant challenges arise from the fact that those states produced and kept large stocks of fssile materials without international monitoring. Reconstructing their fssile material production histories (“nuclear archaeology”) will be essential. While related methods need to be further developed and demonstrated, the chapter discusses how to build initial confdence in this area and prepare the ground for future fssile material