Report by the Special Committee of the National Security Council to the President 1
Development of Thermonuclear Weapons
1. By letter to Mr. Souers dated November 19, 1949, the President designated the Secretary of State, the Secretary of Defense, and the Chairman of the Atomic Energy Commission as a special Committee of the National Security Council to make recommendations
- “as to whether and in what manner the United States should undertake the development and possible production of ‘super’ atomic weapons”, and
- “as to whether and when any publicity should be given to this matter.”
2. The nature of the decision on which the Committee has been called upon to make recommendations needs to be defined with some precision. Systematic theoretical investigations on the possibilities of a thermonuclear weapon were undertaken at Los Alamos in the fall of 1943, and some work on this problem has been going on since that time (Appendix A).2 … Assuming a continuation of the present [Page 514] program at the present rate, however, it would be many years before a test of a thermonuclear weapon would be possible.
The question presented is whether the United States should undertake at this time an accelerated program to determine the feasibility of a thermonuclear weapon, should continue its research at the present rate, or should place a moratorium on further work in this field.
3. An all-out effort leading to both a feasibility test and quantity production of “supers” would seriously impair the efficiency and output of the fission bomb program, but there appear to be no advocates for this type of effort. Technical studies of the Atomic Energy Commission indicate that an accelerated research and development program to test the feasibility of such a weapon (as distinguished from a quantity production program) would require a minimum time of three years; that with such a target date other weapon developments now under way, principally lighter and smaller weapons aimed at improved deliverability … could probably still be carried out, but not with the care and refinement originally planned; that this probable decrease in refinement would not be sufficiently important to serve as a deterrent to an accelerated effort on thermonuclear research and development (Appendix B).3 The important consideration from a military point of view appears to be that the most advantageous rate and scale of effort would be such as to produce a weapon for testing as soon as possible without significant impairment to the quantity output of fission weapons as scheduled (Appendix C).
4. In the present state of knowledge, it appears that there is at least a 50–50 chance that a thermonuclear weapon will be feasible, but this cannot be determined except by actual test (Appendix B, par. 1 and par. 17).
5. It is estimated on the basis of technical studies made by the Atomic Energy Commission and the Department of Defense that an accelerated program, including ordnance and carrier development, is within the capabilities of the United States from the point of view of money, materials, and industrial effort.
6. Knowledge as to whether the thermonuclear bomb is or is not feasible and knowledge as to its potentialities and limitations, if feasible, are of importance to military planning and foreign policy planning (see Appendix C). It should be recognized, however, that the failure of any given test may not conclusively demonstrate that other methods might not be feasible.
7. It must be considered whether a decision to proceed with a [Page 515] program directed toward determining feasibility prejudices the more fundamental decisions (a) as to whether, in the event that a test of a thermonuclear weapon proves successful, such weapons should be stockpiled, or (b) if stockpiled, the conditions under which they might be used in war. If a test of a thermonuclear weapon proves successful, the pressures to produce and stockpile such weapons to be held for the same purposes for which fission bombs are then being held will be greatly increased. The question of use policy can be adequately assessed only as a part of a general reexamination of this country’s strategic plans and its objectives in peace and war. Such reexamination would need to consider national policy not only with respect to possible thermonuclear weapons, but also with respect to fission weapons—viewed in the light of the probable fission bomb capability and the possible thermonuclear bomb capability of the Soviet Union. The moral, psychological, and political questions involved in this problem would need to be taken into account and be given due weight. The outcome of this reexamination would have a crucial bearing on the further question as to whether there should be a revision in the nature of the agreements, including the international control of atomic energy, which we have been seeking to reach with the U.S.S.R.
8. There is evidence which leads to the belief that the Soviet Union prefers to put its chief reliance on winning the cold war rather than precipitating a hot war. There is also ground for the belief that the Soviet Union would prefer not to use weapons of mass destruction except in the event of prior use by others. These assumptions might appear to argue for renunciation by the United States of work in the field of thermonuclear weapons. We cannot safely assume, however, that these hypotheses are correct. Even if they are correct, it cannot be assumed that the Soviet Union would forego development of this weapon any more than she has been willing to forego the development of the fission bomb. Sole possession by the Soviet Union of this weapon would cause severe damage not only to our military posture but to our foreign policy position.
9. There is also the question of possible effect on Soviet attitudes and actions of a decision to proceed with a program to test the feasibility of thermonuclear weapons.
a. Would a decision on the part of the United States to go ahead with an accelerated program cause the Soviet Union to press ahead in this field more vigorously? The theoretical possibilities of a thermonuclear reaction have long been known; as early as 1932 there were suggestions by Russian scientists and others that thermonuclear reactions might release enormous amounts of energy (Appendix A). The [Page 516] Soviet Union probably has felt it could not make any other assumption than that the United States is working on such a weapon, especially in view of the public discussion that has already taken place. It is difficult to escape the conclusion that the Soviet Union will make an intensive effort to produce thermonuclear weapons. A decision to accelerate our program may cause the Soviet Union to increase the priority of these efforts. Knowledge by the U.S.S.R. that we had successfully completed development of a thermonuclear weapon might have the effect of increasing the probability that the USSR would successfully develop a similar weapon. These are risks which are difficult to measure, but which we must frankly face up to if a decision is made to accelerate our development program.
b. It does not appear likely that the character of United States military developments will have a decisive effect on Soviet military developments or be the cause of an arms race. The Soviet decision to reequip its armies and devote major energies to developing war potential, after the end of the war and at a time when we were disbanding our armies, was based on considerations more profound than our possession of the atomic weapon.
10. a. The possibility of the Russians’ developing a thermonuclear weapons capability, added to their probable growing fission bomb capability, re-emphasizes the importance of effective international control of the entire field of atomic energy. Even if we can find a new approach to the control of atomic energy which would be acceptable to us and to our allies, and which offers greater prospect than the U.N. plan of being negotiable with Russia, the necessary negotiations probably could not be completed in less than a year and a half to two years. But to delay an accelerated program of development for such a period in the absence of adequate assurance that work in the Soviet Union had been similarly delayed, would measurably increase the prospect of prior Soviet possession of thermonuclear weapons.
b. It has been suggested that a decision should be deferred until an approach has been made to the Soviet Union proposing that both nations forego work in the field of thermonuclear weapons. If such a proposal were coupled with a plan for the necessary safeguards to insure that the renunciation was in fact being carried out—these safeguards necessarily involving an opening up of Soviet territory—it is the view of the Department of State that the proposition would be unacceptable to the Soviet Union to the same degree that the United Nations plan for the control of atomic energy is unacceptable. If not coupled with such safeguards, it is not believed that sufficient assurance would be gained from such an agreement to make it worth while.[Page 517]
11. In the light of the foregoing considerations, the following recommendations are made:
- That the President direct the Atomic Energy Commission to proceed to determine the technical feasibility of a thermonuclear weapon, the scale and rate of effort to be determined jointly by the Atomic Energy Commission and the Department of Defense; and that the necessary ordnance developments and carrier program be undertaken concurrently;
- That the President direct the Secretary of State and the Secretary of Defense to undertake a reexamination of our objectives in peace and war and of the effect of these objectives on our strategic plans, in the light of the probable fission bomb capability and possible thermonuclear bomb capability of the Soviet Union;4
- That the President indicate publicly the intention of this Government to continue work to determine the feasibility of a thermonuclear weapon, and that no further official information on it be made public without the approval of the President.
[Here follow Appendix A, a historical statement, and Appendix B, a staff study, prepared by the U.S. Atomic Energy Commission.][Page 519]
The body of this report is based on a working paper dated January 24, 1950, prepared by R. Gordon Arneson, Special Assistant to Under Secretary of State Webb for atomic energy policy. The working paper is printed in large part in Arneson, “The H-Bomb Decision” (part ii), Foreign Service Journal, June 1969, pp. 25–26. On January 24, Secretary Acheson approved the working paper as a draft report to the President and transmitted it to Secretary Johnson and Commissioner Lilienthal.
The Special Committee (Acheson, Johnson, and Lilienthal) considered and approved the working paper at a meeting of January 31, making a limited number of modifications. The session is described in Lilienthal, pp. 623–632, and in Acheson, pp. 348–349. The Special Committee immediately proceeded to the White House where President Truman indicated his approval of the report. The White House meeting is not documented in the files of the Department of State, but is described in Lilienthal, pp. 632–633, and in Acheson, p. 349.
Later on January 31, the President released the following statement:
“It is part of my responsibility as Commander in Chief of the Armed Forces to see to it that our country is able to defend itself against any possible aggressor. Accordingly, I have directed the Atomic Energy Commission to continue its work on all forms of atomic weapons, including the so-called hydrogen or super-bomb. Like all other work in the field of atomic weapons, it is being and will be carried forward on a basis consistent with the overall objectives of our program for peace and security.
“This we shall continue to do until a satisfactory plan for international control of atomic energy is achieved. We shall also continue to examine all those factors that affect our program for peace and this country’s security.” (Public Papers of the United States: Harry S. Truman, 1950, p. 138)↩
- Appendix A, a historical statement prepared by the U.S. Atomic Energy Commission, is not printed. The statement summarized past research and development in the field of thermonuclear weapons.↩
- Appendix B, a staff study prepared by the U.S. Atomic Energy Commission, is not printed. The study discussed the requirements for and feasibility of construction of the hydrogen bomb, as well as the characteristic of the weapon.↩
- Interdepartmental efforts pursuant to this recommendation resulted in the preparation of NSC 68, “United States Objectives and Programs for National Security,” a report to the President, April 7, 1950. For the text of NSC 68 and related documentation, see pp. 234 ff.↩
- Prepared by the Department of Defense.↩