Unmaking the Bomb: A Fissile Material Approach to Nuclear Disarmament and Nonproliferation

Harold A. Feiveson, Alexander Glaser, Zia Mian, and Frank N. von Hippel (Cambridge, MA, The MIT Press, 2014) ISBN 978-0262027748 (hardcover), $24.

All nuclear weapons require fissile materials — plutonium and/or highly-enriched uranium (HEU) — to function. As many of the world’s nuclear powers reduce their stockpiles of weapons, an issue that will come to the fore is that of securing and eventually disposing of the global supply of excess fissile materials. This book describes the history, production, current stockpiles, and uses of fissile materials, and sets out possible policies for reducing and eventually eliminating them. The centerpiece policy is a proposed Fissile Materials Cutoff Treaty (FMCT), which the authors argue would also complement nonproliferation efforts.

The authors of this volume are well-qualified to address the dangers posed by nuclear materials. All of them are associated with the Woodrow Wilson School of Public and International Affairs at Princeton University, and have between them decades of experience with the science and politics of nuclear weapons and fissile materials. All are also founders of the International Panel on Fissile Materials, an organization through which scholars and diplomats work to inform their governments of the dangers of fissile materials.

The book is fairly compact. Its roughly 185 pages of text include a preface, introductory chapter, and nine other chapters distributed in three sections titled How the Nuclear World Emerged, Breaking the Nuclear Energy-Weapons Link, and Eliminating Fissile Materials. An additional 90 pages offer appendices detailing the current global inventory of enrichment and nuclear fuel-reprocessing plants, extensive notes, glossary, bibliography, and a comprehensive index.

The introduction offers an overview of the fissile materials situation. For weapons alone the world’s nuclear powers collectively produced over 2,000 metric tons (MT) of HEU and about 250 MT of Pu. In addition to weapons materials there are supplies of HEU in civilian and military research and naval reactors, as well as some 260 MT of plutonium that have been separated from spent civilian power-reactor fuel rods. The present stockpile of weapons-useable fissile materials amounts to about 1,900 tons, enough for over 100,000 nuclear weapons.

Chapter 2 supplies background material: a survey of the discovery of nuclear fission, the concept of critical mass, techniques for enriching uranium and synthesizing plutonium, reactor designs, the dangers of spent reactor fuel, fission and fusion bombs, and the proliferation danger posed by reactor-grade plutonium and centrifuge technologies. This will be familiar ground to readers of nuclear history, but I did learn one fact: that the global inventory of separated weapons-useable neptunium could be on the order of a ton!

Chapter 3 reviews the history of HEU and plutonium production in every country that ever possessed nuclear weapons. The largest producers were the United States (about 960 MT total) and Russia (~1,400), but quantities on the order of tens of tons were also produced by the “smaller” nuclear powers. This chapter also reviews the various routes by which nuclear technology and expertise have spread since Hiroshima and Nagasaki. In addition to espionage and inter-governmental exchanges for either development of weapons or “peaceful” trade, much proliferation can be traced to President Eisenhower’s “Atoms for Peace” initiative which distributed reactors fueled with HEU to a number of nations. Chapter 4 offers a sort of executive abstract of Chapter 3, summarizing stocks of fissile material by country and intended use. As of the end of 2012 global stockpiles of HEU and separated plutonium amounted to about 1,380 and 490 tons, respectively. There are, however, significant uncertainties in these numbers (equivalent to several thousand weapons) as only the non-weapons states are required to report material holdings to the IAEA and allow verification visits. The authors stress the need for more detailed declarations of materials and independent analyses of the operating history of production facilities.

Section II explores the connections between fissile materials, nuclear power, and nuclear proliferation. As remarked above, “Atoms for Peace”-type programs prompted much “latent” proliferation: dozens of countries now have available the technology, materials, and expertise to make nuclear weapons if they decided to. The authors advocate eliminating HEU and plutonium from civilian fuel cycles and phasing out spent-fuel reprocessing. More controversial will be their notion that countries may have to give up some control of nuclear technologies in favor of a regime in which nuclear power is generated by “a globally agreed set of rules that apply equally to all states.” However, they leave unstated what sort of overseeing agency would be involved.

Chapters 6 and 7 examine separated plutonium and HEU. The approximately 260 tons of “civilian” plutonium is the legacy of fuel-reprocessing efforts initiated in anticipation of breeder-reactor programs. But the growth of nuclear power has been less dramatic than predicted 40 years ago, and estimates of recoverable uranium ores have grown substantially; breeders and reprocessing are now no more economical than once-through fuel cycles. The case of HEU is trickier because of the spectrum of venues involved and the enormous investments in existing systems. Numerous civilian research reactors utilize HEU; there are also medical-isotope production reactors, reactors for testing new core designs, and high-neutron-flux reactors for testing weapons components. In many of these installations the HEU fuel can be replaced with “high-density” low-enriched uranium (LEU) fuel, but a particular concern is naval-propulsion reactors: both the U.S. and Britain use “lifetime core” designs intended to operate for 30-40 years without refueling. The Department of Energy has indicated that a shift to LEU might eventually be practical, but this would be a decades-long conversion involving future generations of vessels.

Section III moves the discussion into the political arena. Chapter 8 explores the possible scope and verification requirements of a FMCT. The UN General Assembly has agreed to a resolution calling for banning fissile production for nuclear weapons, but discussions have been blocked by Pakistan. In theory, a FMCT would prohibit production of fissile materials for weapons and enrichment of uranium except under safeguards, prohibit separation of plutonium, and require the decommissioning or conversion to civilian use of military fissile materials production plants. Verification procedures could be based on existing IAEA protocols along with “managed access” to military facilities to monitor for clandestine diversion of materials to weapons use.

Chapter 9 examines disposal scenarios for fissile materials. For HEU the most sensible option is down-blending into fuel for power reactors as exemplified by a U.S. program to purchase 500 tons of excess Russian HEU which was downblended to LEU and sold to American utilities. Separated plutonium can be mixed with depleted uranium oxide to form mixed-oxide fuel (MOX), but MOX fabrication plants have been plagued by cost overruns and poor production records. The best approach for Pu may be burial in deep (~ 5 km) sealed-off boreholes. A striking statistic is that even if they were to retain 5,000 operational warheads each, the U.S. and Russia could respectively declare as excess roughly one-half and three-quarters of their weapons materials.

In their summary and conclusions, the authors urge all countries possessing fissile materials to cap and reduce civilian and military stockpiles and to approach regulation as if the world is preparing for nuclear disarmament. One striking statement: “In time, a decision might be made to forgo nuclear power entirely;” however, the authors offer no comments on the attendant issues of cost, environmental impact, and resource consumption. Overall, the authors convinced me that the world’s stockpile of fissile material is adequate to supply civilian and military needs well into the future and that no more needs to be produced. But I am skeptical that a FMCT would meaningfully complement arms-reduction efforts. The nuclear powers can recycle weapons materials into new warheads for decades to come. The U.S. and Russia are reducing their numbers of deployed warheads, but military planning still includes nuclear postures. Life-extension and weapons-platform programs carry huge budgets, political clout, and bureaucratic inertia.

The world took decades and trillions of dollars to get into its current fissile-materials situation, and will take more decades, more trillions, and a very different international environment to get this genie back into the bottle. But we have to try, and a FMCT would be a strong place to start. This book should be read and carefully considered by every serious student of the world nuclear situation.

Cameron Reed
Department of Physics, Alma College, Alma, MI

These contributions have not been peer-refereed. They represent solely the view(s) of the author(s) and not necessarily the view of APS.