138. Record of Meeting of the Committee of Principals1


  • See Attached List2


  • (1) Memorandum for the Members of the Committee of Principals dated June 14, 1966, from Adrian S. Fisher, Acting Director, ACDA, subject: Proposed U.S. Arms Control Initiatives (U).3
  • (2) Memorandum for the Members of the Committee of Principals dated June 9, 1966, from William C. Foster, Director, ACDA, subject: Threshold Test Ban (TTB) Proposal (U).4
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I. Threshold Test Ban Proposal

There was agreement with the Secretary of State’s suggestion that he prepare a memorandum for the President summarizing the argumentation and issues on the threshold test ban proposal. The Secretary said he would attach to the memorandum the more detailed comments that have been submitted from the various agencies.

II. Non-Proliferation Treaty

The Secretary of State said he would circulate as soon as possible for consideration by the Principals a revised non-proliferation treaty draft. The Secretary said the revised draft would be a more simplified version of Article I than the present U.S. draft and would focus on “physical access.”


Mr. Fisher outlined the principal reasons why the threshold proposal had been brought to the Principals once again, referring to the AFTAC report showing that seismic identification was excellent for events above 4.75, thus indicating a threshold could be verified without on-site inspection;5 Mr. Fisher said it was, moreover, important to keep the dialogue with the Soviets on non-proliferation open and it appeared that the threshold proposal was at this time the only way we could take some initiative in this area. It was, he said, ACDA’s belief that the question should be raised with the President and he hoped the Committee of Principals would agree to submit the issues to the President.

Mr. Fisher noted the AEC and JCS objections to the threshold proposal. He said it was, nevertheless, ACDA’s view that the proposal was in the U.S. interest, recognizing that it would however require considerable political effort to obtain its acceptance in Congress. The inhibitions placed on non-nuclear powers would inhibit them, both technically and in a political sense, from achieving their nuclear ambitions. He said he recognized, however, that technically the threshold ban would not prevent a test by presently non-nuclear powers if sufficient effort were made to conduct one but nevertheless the inhibition would be there. Mr. Fisher commented that within the government the discussion had tended to go back and forth between moving in the non-proliferation field by enlarging the present limited test ban treaty or by making a new effort for a non-proliferation treaty.

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The Secretary of State said the first question was whether the proposal was in the U.S. interest and if the answer was affirmative the second was should we attempt to achieve it by formal agreements or by unilateral undertakings.

Chairman Seaborg referred to the concerns regarding the proposal that had been expressed in his letter of June 16 to Mr. Fisher.6 He said the Commission’s view was that the IDA Study was overly optimistic with regard to possible modifications under a threshold test ban [less than 1/2 line of source text not declassified]for ABM warheads.7 Chairman Seaborg made particular reference to the last two paragraphs of Enclosure II of his letter, the weapons laboratories comments.8 [13 lines of source text not declassified]

The Secretary of State commented that the problems described by Chairman Seaborg would apply doubly to a comprehensive test ban. He asked what our assessment was as to where the Soviets are with their ABM development. Admiral Raborn said there was some evidence that they are up to where the U.S. is at the present time.

Mr. Fisher pointed out that Mr. Foster of the Department of Defense took a different view than the weapons laboratories with respect to ABM warhead developments that would be possible under the threshold test ban.

The Secretary of Defense said Mr. Fisher’s comment on Mr. Foster’s views dealt with the first point he had wished to make, and the second was to inquire about the observations made by Chairman Seaborg in his letter to Mr. Fisher regarding the difficulties of differentiation and identification of events under a threshold test ban.

Chairman Seaborg said there was no real assurance that we could test at 30 KT and not violate a threshold ban, [1-1/2 lines of source text not declassified].

Mr. Fisher commented that the 30 KT figure was based on the AFTAC studies. He also noted the hidden asymmetries between nuclear and non-nuclear powers that would make it more difficult for non-nuclear powers to initiate a test program under the threshold limitation.

When Mr. Marks noted the differences between the ACDA and AEC judgments on the inhibitions a threshold ban would place on non-nuclear powers, Mr. Fisher reviewed the political as well as the technical inhibitions that ACDA believed would apply to non-nuclear powers under a threshold ban.

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The Secretary of State said that a non-nuclear state might well merely declare that it had a nuclear weapon but say it was not going to test it; he said if the Israelis made such a statement he would probably be inclined to believe them.

Dr. Scoville commented on the ABM warhead need, saying he did not understand why we could not make better use of existing weapons technology [1-1/2 lines of source text not declassified]. We already have this capability, he said, in the lower and higher yield ranges. The Vice President said this was a point that needed to be examined carefully. Chairman Seaborg said the IDA Study had examined the question raised by Dr. Scoville. Mr. Keeny commented that the IDA Study had merely looked at the existing devices. Chairman Seaborg said it might be possible to modify [less than 1/2 line of source text not declassified] and have some type of defense against ICBM’s.

The Secretary of Defense then summarized the objections and questions he believed had been raised by the AEC to the threshold proposal. They were, he said, that the threshold ban would not get us very much in the way of inhibiting proliferation; the price would be some reduction in our ABM capability, if it were decided to go this route; there was some question as to our ability to distinguish events above 4.75; and finally the problems raised by the peaceful uses question.

In response to the Secretary of State’s question about the possibility for cheating above 4.75, Admiral Raborn said the margin for cheating was very good. He said the Soviets could conduct two or so clandestine tests a year unless we had on-site inspection. General Johnson noted that the studies that have been made are for a period when the Soviets have been testing in their normal test areas and not attempting clandestine tests. Mr. Fisher stated that the AFTAC study indicated there would be an average of one event a year that would be unidentified by seismic means and that these events were almost all in the Kamchatka area. Moreover, for this area no low coupling material was available—therefore it would not make sense for the Soviets to go to an area where the coupling was not advantageous in an attempt to test illegally what they could test legally in other areas where coupling was more satisfactory for their purposes. Admiral Raborn restated his view that the Soviets could test clandestinely two tests a year. Dr. Scoville pointed out that the U.S. would be able to spot all suspicious events whether identified or not and to focus on these events with intelligence resources. Admiral Raborn said we could not, however, prove to the world any of our conclusions.

After further discussion of the coupling question, Mr. Fisher pointed out that decoupling would be perfectly legal under the threshold test ban. Chairman Seaborg said there was no question but that the ABM problem was the most bothersome of the difficulties AEC had with the threshold proposal. He suggested that the U.S. go on as fast as possible [Page 338]to meet our testing requirements for ABM warheads and in a year or two we would have most of our needed testing for this purpose completed.

The Secretary of State asked about the effects of a threshold at 5.0. Chairman Seaborg said this would help with the ABM problem but of course it would not be much of an inhibition on non-nuclear countries.

Admiral Raborn said the intelligence community was agreed that a threshold test ban would have little effect in halting proliferation. Mr. Fisher questioned this assessment, pointing to the technical and political inhibitions he believed would apply. He said, moreover, that Soviet-U.S. agreement on a threshold ban would itself have a very real effect on potential nuclear countries. The Secretary of State said a threshold ban might, during the process of ratification that would take place in potential nuclear countries, precipitate a debate over the question of going or not going nuclear.

Mr. Marks wondered if our posture would not suffer more by making the threshold test ban proposal and having the Soviets respond with a call for a moratorium than in not making the proposal. Mr. Fisher pointed out that new verification data will not remain unknown for very long and said that when it becomes known the U.S. will either have to be in favor of a threshold proposal or change its present position of being prepared to ban all tests that can be adequately verified.

The Vice President wondered if a threshold test ban would really inhibit proliferation. Mr. Fisher said there was no certainty it would prevent proliferation but it would make it more costly and more difficult and therefore decrease the likelihood of proliferation. He said it was ACDA’s conclusion that this was the only way we could move at the present time to inhibit proliferation in view of our policy on options we were keeping open on NATO nuclear questions. He said it was either moving on the threshold proposal or doing nothing. He added that the question for the meeting really was whether the issue should not be put to the President.

The Secretary of State said he believed the President should be informed of the discussion. He thought it would be advisable for him to prepare a two or three page memorandum for the President, digesting the issues and arguments involved, with the detailed comments from various departments attached.

The Vice President questioned the value of a country going nuclear if a potential adversary was likely to develop an ABM system, and he wondered if the cost factors would not be too high for various potential nuclear countries. The Secretary of State said he believed India, Israel, Sweden and others could afford to go nuclear, though they might underestimate the ultimate cost to them of doing so.

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Chairman Seaborg noted that with respect to the 4.75 limitation, the AEC would have to instruct the laboratories not to go above 10 to 20 Kt in their testing in order to avoid a risk of treaty violation. [2 lines of source text not declassified]

In response to the Vice President’s question as to the real objectives of a threshold ban, Mr. Fisher said it was both turning down the nuclear arms race and inhibiting the proliferation of nuclear weapons. The Secretary of State commented that in terms of creating an atmosphere of peace the threshold test ban would certainly not be comparable to Soviet action for peace in South East Asia.

The Vice President said that if the threshold proposal did not curb nuclear technology it was not clear how it would really inhibit the proliferation. Chairman Seaborg said that it was necessary to settle the Plowshare question before any decision was made on the threshold proposal.

The Secretary said that if it were agreeable with the Vice President, he would put together for the President a digest of the issues on the threshold proposal. He said he would like to review the issues himself before making final judgment on the proposal. He commented that he was concerned about the problem of ultimate cheating and the problem of defending this possibility in any U.S. debate on a threshold proposal.

The Secretary of State said he would like to turn for a moment to the question of a non-proliferation treaty. He said the Soviet representative in Geneva had seemed to put an emphasis on “physical access.” He thought we might consider the possibility of a simplification of Article I of the U.S. draft treaty. The Secretary of Defense said he completely agreed with this suggestion.

The Secretary of State said we should consider a simplified Article I that would prohibit the transfer of physical access to nuclear weapons. He said he would be sending to other members of the Committee of Principals as soon as possible a simplified text for their consideration. He added that it may be that the Soviets are beginning to move and would be prepared to gamble on their estimate that the MLF is dead.

Mr. Rostow asked if a prohibition on physical access would be compatible with joint ownership. The Secretary said he did not believe ownership was relevant to the problem of proliferation, although he did not believe that we should be opposed to other countries paying some of our costs if they wished to.

  1. Source: Johnson Library, National Security File, Subject File, Disarmament, Committee of Principals, Vol. 3, Box 14. Secret; Restricted Data. The meeting took place in the Secretary of State’s office. No drafting information appears on the source text, though Lawrence D. Weiler is listed as Reporting Officer on the attached list of 23 participants. Seaborg’s notes of this meeting are in Seaborg, Journal, Vol. 12, pp. 614 and 628.
  2. Not printed.
  3. The memorandum attached a draft memorandum from Fisher to the President recommending that he propose a new test ban agreement extending the present Limited Test Ban Treaty to cover verifiable underground tests—a threshold test ban treaty. (Washington National Records Center, RG 330, OSD Files: FRC 70 A 4443, 388.3, June 1966)
  4. The memorandum transmitted a revised draft position paper on the Threshold Test Ban Treaty, the May 26, 1966 ACDA draft position paper as amended June 9. (Ibid., OSD/AE Files:FRC 72 A 4120, #3 Plowshare (Panofsky Panel)—1966)
  5. The report by Dr. Evernden of the Air Force Technical Applications Center, “Critique of U.S. Capability of Discriminating between Earthquakes and Explosions,” was distributed in February 1966, but has not been found.
  6. A sanitized version of the letter is in Seaborg, Journal, Vol. 12, pp. 620-622. The original has not been found.
  7. IDA Study S-235, “Special Nike-X Warhead Study,” has not been found.
  8. A sanitized version of Enclosure II, AEC Weapons Laboratories Comments on the IDA Study, is in Seaborg, Journal, Vol. 12, pp. 626-627.