An Exchange on Stockpile Confidence

Correspondence1John D. lmmele and Paul S. Brown An Exchange on Stockpile Confidence Steve Fetter T o the Editors: We have read with great interest the article by Steve Fetter recently published in lnternafioizal Security.’ We are concerned with the fundamental thesis of Fetter and others who believe that technical and political confidence in the reliability of U.S. weapons can be high during a comprehensive test ban (CTB). We believe that nuclear weapons are very much like other types of high-technology military equipmenttanks , rockets, airplanes, radar systems, etc. However, while these other military systems are extensively tested and retested during development and after deployment , nuclear weapons are certified to function properly over a wide range of stressful conditions on the basis of only a handful of nuclear tests. History has shown that continued nuclear testing has been necessary to maintain the reliability of the nuclear stockpile. We have found that Fetter’s summary of U.S. stockpile experience is misleading in many respects. While he agrees at first that “the likelihood of problems with complex technologies is chronically underestimated,”* he later discounts the likelihood and importance of problems in the case of nuclear weapons. In several instances, he describes design strategies that could provide a degree of insurance against a CTB. In fact, these strategies have long been part of our design approach. The University The work of lmmele and Brown was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract W-7405-Eng-148. Iohn D. Zmmele is responsible for the physics divisions at Lawrence Liverinore National Laboratory that design fission, fusion, arid nuclear directed-energy weapons. He preuiously managed activities such as the Laboratory‘s advanced coriveritiorinl ordnance effort and the Peacekeeper (MX)warhead dezieloprnent. Paul S. Brown is the Livermore Laboratory’s Assistant Associate Director for Arins Control arid was a delegate to the U.S.-USSR Nuclear Test Experts Meetings in Geneva, 7986. He has directed deuelopineiit of computer codes to simulate nuclear explosions and to model explosive iiiteractions in geologic media. Steve Fetter is a research fellow at the Center for Science and Znternatiorial Affairs, Kennedy School of Government, Harziard University. He is the author of Toward a Comprehensive Test Ban, recently published by Ballinger. He received mi S.B. in physics froin flie Massachusetts Institute of Technology and a Ph.D. porn the University of California, Berkeley. He runs a postdoctoral fellozu at Lnwreiice Liverinore National Laboratory before corning to CSIA. 1. Steve Fetter, ”Stockpile Confidence Under a Nuclear Test Ban,” International Security, Vol. 12, No. 3 (Winter 1987188), pp. 132-167. 2. Ibid., p. 133. International Security, Summer 1988 (Vol. 13, No. 1) 01988by the President and Fellows of Harvard College and of the Massachusetts Institute of Technology. 196 Correspondence I 197 of California Scientificand Academic Advisory Committee (SAAC),comprising senior scientists and defense experts, recently reviewed the nuclear testing practices at the Livermore and Los Alamos Laboratories. They concluded that "the Laboratories have been acting under a plan that emphasizes the necessity to be prepared for a possible CTB."3 There are a number of reasons for continued nuclear testing. The most important is the need to be able to develop new weapons in response to advances in nonnuclear technology and changes in political strategy. Major emphasis is also placed on the process of modernizing nuclear weapons to improve their safety, security, and survivability . However, Fetter's article and our commentary concentrate on stockpile confidence and the need for nuclear testing. Some of the points mentioned in this commentary are elaborated in a recently released, unclassified report to Congress.* The reader may also wish to consult the Congressional Research Service study5for a thorough survey of all of the test ban issues, pro and con. The question we address here is whether weapon confidence can keep pace with the requirements of U.S. nuclear deterrence. This will be an important issue for as many years as it takes to achieve a massive reduction in the numbers of nuclear weapons and a decrease in our dependence on them for national security. It seems to us that the burden of proof in the matter of...