Foreign Relations of the United States, 1961–1963, Volume VII, Arms Control and Disarmament

301. National Intelligence Estimate⁰

NIE 4-63

Washington, June 28, 1963.

LIKELIHOOD AND CONSEQUENCES OF A PROLIFERATION OF NUCLEAR WEAPONS SYSTEMS

The Problem

To estimate the capabilities and intentions of additional countries to develop and produce nuclear weapons and compatible delivery systems over the next decade; and to estimate the consequences thereof.

Conclusions

A. With the increasing availability of uranium, and nuclear technology and technicians, the development of a minimal nuclear weapons capability has come increasingly within the reach of nonnuclear states. A program for one or two low-yield fission weapons a year would cost, through the first detonation, about $140-$180 million and some $20-$30 million a year thereafter. However, costs rise steeply for more than a minimal program and become very large when advanced delivery systems and compatible weapons are required. Political and military considerations are likely to prove more important in determining the pace and scope of nuclear diffusion than differences in national wealth and technical skill. Where the motivation is strong enough, a country might attempt to overcome a lack of native resources by importing materials, technology, and technicians, or even weapons themselves. (Paras. 1-6)

B. We believe that eight countries, in addition to France, have the physical and financial resources to develop an operational nuclear capability (weapons and means of delivery) over the next decade. However, we believe that only Communist China has actually started a weapons program. The Chinese may be able to detonate a first nuclear device by early 1964, but a more likely date is late 1964 or beyond. Approximately two years after a test the Chinese could probably produce their first crude fission weapon. [2 lines of source text not declassified] Thus far the remaining countries—India, Japan, Sweden, Canada, Italy, and West Germany—have limited their nuclear programs to demonstrably peaceful purposes. They will, however, almost certainly continue development of their peaceful nuclear programs, some to a point which would significantly reduce the time required to carry through a weapons program. (Paras. 7-21)

C. We do not believe that the explosion of a first device, or even the acquisition of a limited nuclear weapons capability, would produce major changes in Communist China’s foreign policy in the sense that the Chinese would adopt a general policy of open military aggression, or even become willing to take significantly greater military risks. It would, however, increase Chinese self-confidence and prestige and reinforce their efforts to achieve Asian hegemony through political pressures and the indirect support of local “wars of liberation.” India probably would not embark on a nuclear weapons program on the basis of a Chinese detonation of a nuclear device, but is likely to continue its present nuclear program to a point where a crash weapons program could be developed relatively quickly. Japan also would feel an increased sense of pressure, but would be more reluctant than most other countries to develop a weapons capability. We believe the Israelis would probably employ a nuclear capability to intimidate the Arabs, but not to make war forthwith. The Arab States would probably blame the West, particularly the US, and the Soviets would probably finds ways of exploiting the situation. (Paras. 25-31)

D. The French force has as its primary purpose heightening French prestige and assisting France to assume leadership of a Europe less dependent on the US and with a voice in the management and control of Western nuclear power. While many Europeans are in general sympathy with de Gaulle’s objectives, they also fear that the French program will stimulate further nuclear proliferation, erode the NATO concept, and perhaps most important, lead to German acquisition of nuclear weapons. We believe, however, that the Germans will limit themselves to peaceful nuclear programs over the next few years. If the Germans began to believe that their Allies, and especially the US, might not use nuclear weapons in the defense of the Federal Republic, German interest in a national capability would rise. (Paras. 32-37)

E. We believe that the USSR desires to prevent the diffusion of nuclear weapons, but that this desire will not prove so strong as to produce major changes in its policy. The Soviets have thus far proved unwilling to conclude nondiffusion agreements save on unacceptable terms. Even if the Soviets conclude that West Germany was moving toward a nuclear status, they would probably not make radical changes in their policy, but employ instead a mixture of threats, appeals, and proposals for regional disarmament. (Paras. 38-41)

F. Even if the US, the UK, and the USSR could agree on terms of a nondiffusion agreement, Communist China would almost certainly refuse to sign, and French and Israeli adherence would be doubtful. Nevertheless, the very existence of such an agreement would inhibit other nonsignatories and reinforce internal opposition where it already existed. A comprehensive nuclear test ban treaty would impose serious limitations on the development of nuclear capabilities by nonnuclear signatories but would be subject to many of the same difficulties as a nondiffusion agreement. (Paras. 44-46)

G. In strictly military terms, the nuclear proliferation likely to occur over the next 10 years will almost certainly not upset global power relations nor do we believe it will produce major realignments in the relations of states. The impact will be in the political and psychological effects of the existence of such new weapons, the greater unpredictability of relations within and between alliance systems, and the possibility that hostilities arising out of existing or future controversies could escalate into a serious confrontation involving the major powers. (Paras. 47-48)

H. The possession of nuclear weapons may encourage a new nuclear power to pursue policies which might result in a local crisis, but the possibility that such weapons could be used will almost certainly introduce a strong element of prudence into the calculations of regional enemies. As the number of countries with nuclear weapons programs increases, the likelihood of accidental detonation of weapons will also rise, particularly because safety measures are expensive and temptingly easy to dispense with. An unintentional nuclear explosion in some circumstances might even touch off a nuclear exchange, though we believe the major nuclear powers would react cautiously to such an accident. A serious nuclear reactor accident or a nuclear weapons detonation established as unintentional would almost certainly intensify domestic opposition to the country’s nuclear weapons program, and would cause other governments considering a weapons program to hesitate. If US nuclear forces were stationed in the area concerned, there might be considerable regional pressure for their withdrawal. (Paras. 50-54)

[Here follow the Discussion section of the paper and an annex, totaling 21 pages.]

0. Source: Johnson Library, National Security File, National Intelligence Estimates, Estimates 4, Arms and Disarmament. Secret; Controlled Dissemination. A table of contents is not printed. A note on the title page states: “Submitted by the Director of Central Intelligence. Concurred in by the United States Intelligence Board.” A note on the following page indicates that the members of the U.S. Intelligence Board participated in the preparation of this estimate. The Assistant Director, Federal Bureau of Investigation, abstained because the subject was outside of his jurisdiction.