163. Circular Airgram From the Department of State to Certain Posts 1

CA–4864

SUBJECT

  • Recent Developments in Strategic Forces

A. Purpose

1.
This message provides background information and guidance concerning developments bearing on the strategic (nuclear) relationships of the US with the Soviet Union and Communist China.
2.
Posts may, of course, employ freely what has been said publicly by US officials. (Paragraphs C1a, C2f, C5a, b, c, and C6b, c, d below.) The remaining material in sections B and C is available for informal discussions with officials of other governments if they themselves inquire. [Page 512]In view of the complexity of technical and other aspects and the need to relate inter-governmental exchanges with on-going studies and conclusions in Washington, it is requested that serious governmental inquiries be referred to Washington for guidance. We do not wish press stories out of other capitals about USG views on ABMs or our assessment of strategic facts. It is expected there will be further public discussion of these matters here in connection with presentations to Congress. Therefore suggest posts abroad not use this material for background briefings but refer press inquiries to Washington.
3.
It is recognized that the material will not be equally useful or appropriate for all posts. Additional classified information will in due course be provided to allies.
4.
Policy implications of the developments discussed below continue under review. On the one hand, this review may lead to further arms control efforts. On the other hand, further consideration is being given to US deployment of an anti-ballistic missile (ABM) system. The material below is not intended to prejudge or prejudice either approach.
5.
Addressee posts are requested to report any significant and spontaneous host country press or other comments on strategic developments. Negative reports are not required.

B. General Considerations

1.
Objectives of US Strategic Forces
a.
Our strategic forces are the product of necessity rather than of aggressive designs against any nation. Changes in our strategic forces will not adversely affect US efforts for constructive interchange with the Soviet Union and with Communist China. Rather, further changes will afford a prudent basis for continuing such efforts.
b.
We would much prefer to see strategic armaments remain at pres-ent levels and, indeed, would hope to reduce them. But to date, many of our efforts to halt the arms race have not borne fruit. We shall continue these efforts, but meanwhile, we must also continue to maintain the strength and flexibility essential to deterrence.
c.
It is in our interest, and that of our allies, to preclude any possibility of miscalculation by the Soviet Union or Communist China. Preventing miscalculation and maintaining deterrence requires the continuing effectiveness of tactical nuclear and non-nuclear capabilities as well as strategic capabilities. In the Soviet case our purpose of maintaining a spectrum of capabilities is to assure that they are not tempted to exploit mutual deterrence at the strategic level by risking conflict at lower levels of the hostilities spectrum.
d.
Over the past twenty years, the US has developed forces and arms control techniques to ensure that its military strength will remain constantly [Page 513]responsive to the peaceful purposes of deterring aggression and preventing the outbreak of war. Our concern is to preserve military stability, for it is from instability that tension, miscalculations and war could come.
2.
Present Trends in Perspective
a.
In the light of the foregoing objectives, the main points respecting on-going changes in strategic capabilities are as follows:
(1)
Our purposes in maintaining strong strategic capabilities are peaceful.
(2)
The effectiveness of the US strategic deterrent is not impaired by changes in Soviet capabilities, or by the ChiCom nuclear weapons effort.
(3)
There is no gap in strategic technology, including anti-ballistic missile (ABM) technology in the Soviet Union’s favor. In fact US ABM technology is more highly developed.
(4)
Our nuclear guarantees to our allies remain valid.
(5)
Changes in our own strategic capabilities do not reflect any change in our intentions vis-à-vis the Soviet Union or Communist China, but represent prudent measures to maintain deterrence.
(6)
We have no intentions of increasing tensions; we are determined to maintain a strong strategic posture in the face of continuing Soviet and ChiCom efforts.
b.
We desire these points to be understood by the Soviet Union and Communist China as well as others.

C. Questions and Answers

1.
What changes is the Soviet Union making in its strategic offensive and defensive capabilities?
a.
On November 10, 1966 Secretary McNamara stated publicly that the Soviet Union has initiated deployment of an anti-ballistic missile (ABM) system.2 On December 6 he said that the Soviets appeared to have begun an accelerated build-up of Soviet intercontinental ballistic missiles (ICBMs) as well.3
b.
In building up their ICBM force, the Soviets are continuing to disperse their missiles in hardened silos. The Soviets are evidently seeking to remedy to some extent the inferiority and vulnerability of their ICBM deterrent force. We do not find this surprising or alarming.
c.
The first known Soviet anti-ballistic missile (ABM) deployments are in the Moscow area. These may become operational over the next [Page 514]several years. We regard this system as limited in technical sophistication and consider it inferior to our Nike-X anti-ballistic missile development. The Soviet Union has always invested heavily in defensive systems, and their initiation of anti-ballistic missile (ABM) deployment is consistent with past practice. However, we have concluded that they are expending their resources on a system we could readily overcome.
d.
We do not know how far either of these trends in offensive and defensive capabilities will be carried. We shall maintain the effectiveness of our deterrent by retaining the capability to inflict very severe damage on the Soviet Union under any circumstances.
2.
What changes is the US making in its strategic capabilities?
a.
Our Minuteman and Polaris forces have been designed to provide a secure, survivable, non-provocative deterrent which would be capable of inflicting very severe damage on the Soviet Union even if it should initiate a first-strike. Our planned build-up of these systems is now almost complete. We are not now planning further increases in the number of Minuteman and Polaris launchers.
b.
Because we had for some time foreseen the possibility of changes on the Soviet side, including the possibility of anti-ballistic missile (ABM) deployment, we have developed significant qualitative improvements. We now plan to introduce the Minuteman III and Poseidon ballistic missiles in the late 1960’s to replace some of the older versions of Minuteman and many of the present Polaris ballistic missiles.
c.
A principal qualitative change is that Minuteman III and Poseidon will be able to launch heavier payloads than our present missiles. These heavier payloads do not mean that we are planning to increase the megatonnage that could be directed against the Soviet Union. They will add to our ability to launch adequate numbers of devices such as decoys and multiple warheads which will ensure that we can penetrate Soviet defenses.
d.
One point that should be recognized concerning changes in offensive capabilities is that the Soviet Union is introducing quantitative changes whereas the US is now pursuing qualitative changes. As a result, the Soviet Union can be expected to narrow the numerical gap in ICBMs that has for some time existed in our favor. However, more is involved than numbers in determining the effectiveness and significance of strategic forces. Although we could, if there were need, substantially increase our own number of launchers, qualitative superiority will continue to yield a number of advantages.
  • —A more flexible force;
  • —A more accurate force, which is able to employ relatively small warheads with greater effect than would be the case with larger warheads launched with lesser accuracy;
  • —A more survivable force which includes not only ICBMs dispersed in hardened silos but also a substantial, wholly invulnerable sea-based component.
  • —A force with a greater capability to penetrate defenses.
e.
Although we do expect to maintain an overall numerical edge for some time, our emphasis on qualitative improvements will meet our deterrent needs in the face of the probable Soviet offensive build-up and its introduction of anti-ballistic missile (ABMs).
f.
In his December 6 statement Secretary McNamara said:

“It is vital that these three major points are clearly understood by the American public:

  • “1. Even if the new intelligence estimate for mid-1968 proves accurate, the US, without taking any actions beyond those already planned, will continue to have a substantial quantitative and qualitative superiority over the Soviet Union in ICBMs at that time.
  • “2. The US has as many ICBMs today as the latest national intelligence estimate gives the Soviet Union several years hence.
  • “3. Our strategic offensive forces have today and will continue to have in the future the capability of absorbing a deliberate first strike and retaliating with sufficient strength to inflict unacceptable damage upon the aggressor or any combination of aggressors.”

3.
How can we be sure that we can penetrate Soviet anti-ballistic missile (ABM) defenses?
a.
The type of anti-ballistic missile (ABM) defense that technology now permits—and this is true of Soviet technology as well as our own—does not represent a kind of impenetrable umbrella that could offer sure protection against incoming missile warheads.
b.
The way to think of an anti-missile missile is a very advanced interceptor. In effect, it would be assigned to “shoot down” or neutralize an incoming warhead just as a SAM (surface-to-air missile) or fighter might be assigned to intercept a manned bomber.
c.
Depending on the particular ABM techniques, this effort to intercept incoming warheads might take place outside the atmosphere, or it might occur after the warhead has reentered the earth’s atmosphere. Both approaches might be involved, the one supplementing the other.
d.
In confronting this kind of defense, we will employ a number of different techniques which we have been working on for some years. Obviously, we are not going to discuss these in detail. However, broadly speaking, they can be thought of as complicating the defense’s tasks of identifying incoming warheads and of destroying them if they are identified.
e.
A key point is that Soviet defenses would have to intercept a very large number of objects, including large numbers of warheads. In addition to attempting to cope with a large number of warheads, we are sure [Page 516]that they will not be able to distinguish effectively between what might be decoys or other penetration devices and what might be warheads. They would have to “shoot” at everything, and they would exhaust their supply of interceptors in doing so, if they were not already overwhelmed by the scale of attack. In effect, then, we can confront them with more targets than their interceptors could manage.
4.
What about deploying our own Nike X ABM?
a.
In the face of Soviet ABM deployment, we are giving priority to ensuring the effectiveness of our offensive deterrent force. In this way, we are precluding the emergence of an “anti-missile gap” which could occur if we could not penetrate their defenses.
b.
As for the Nike X anti-ballistic missile (ABM) system which we are developing, we are satisfied on technical grounds that it is more advanced than the Soviet system. But like Soviet ABMs, Nike X would not provide “perfect” defense against a large-scale attack by a sophisticated missile force. A major deployment would be costly, and its potential effectiveness would depend in part on such uncertainties as the changes the Soviets might make in their own capabilities in response to such a deployment. Under some assumptions, US defenses would be relatively ineffective. Under other assumptions, US defenses might limit damage and reduce casualties.
c.
A more limited deployment might be effective against some forms of light Soviet attacks or accidents and very effective against a Chinese Communist nuclear missile capability. It could also be designed to protect our strategic offensive forces. (The Soviet system, for example, can be expected to be highly effective against any small nuclear force.)
d.
All of these considerations have a bearing on the question of deploying Nike X. The development effort is being continued, and we are continuing to examine the questions of whether to deploy and what level of defense might be sought. We have not at this time arrived at any decision.
5.
Would the US favor a freeze on ABM deployment?
a.
In his news conference of December 21, 1966 Secretary Rusk made the following statement in response to questions:4

“We would regret very much the lifting of the arms race to an entirely new plateau of major expenditures.

“As you know, we made earlier to the Geneva Conference proposals for freezes and limitations on the further production of offensive and defensive nuclear weapons.

[Page 517]

“We would like to see some means developed by which both would not have to go into wholly new and unprecedented levels of military expenditure, with perhaps no perceptible result in the total strategic situation.

“This is a matter that is before the Geneva Conference. We and the Soviet Union are co-chairmen.

“I presume that there will be further contacts on this matter. But I cannot go into more detail at this point.”

b.
Secretary Rusk added that there has been no progress on the matter thus far at the Geneva Conference, that the Conference is to resume in February, and that he could not anticipate at this point what might be the results.
c.
Our original freeze proposal to which Secretary Rusk referred was in the following terms:

“The US, the Soviet Union and their respective allies should agree to explore a verified freeze of the number and characteristics of strategic nuclear offensive and defensive vehicles. For our part, we are convinced that the security of all nations can be safeguarded within the scope of such an agreement and that this initial measure preventing the further expansion of the deadly and costly arms race will open the path to reductions in all types of forces from present levels.”5

d.
Several suggestions have been made for freezing or limiting anti-ballistic missile (ABM) deployment only, that is without a corresponding freeze on offensive systems. We have not proposed any of these approaches. They continue to be studied.
6.
How significant are Communist China’s nuclear weapons and missile development programs?
a.
We had estimated that Communist China would be able to deploy medium range ballistic missiles (MRBMs) initially in the next several years. They have not tested a short-range guided missile with a nuclear warhead, and they thus seem to be progressing on a schedule consistent with our estimate.
b.
While they do not yet have a militarily useful nuclear capability, they could pose a potential nuclear threat against their neighbors in Asia within a few years. At the time of the initial ChiCom nuclear test in 1964, President Johnson made the following statement concerning our defense commitments:

“The US reaffirms its defense commitments in Asia. Even if Communist China should eventually develop an effective nuclear capability, that capability would have no effect upon the readiness of the US [Page 518]to respond to requests from Asian nations for help in dealing with Communist Chinese aggression. The US will also not be diverted from its efforts to help the nations of Asia to defend themselves and to advance the welfare of their people.”6

c.
The President also announced that it would be our policy to provide support to non-nuclear countries threatened by ChiCom “nuclear blackmail”.
d.
In October 1966 in Malaysia the President made the following further statement: “The leaders of China must realize that any nuclear capability they can develop can—and will—be deterred. A peaceful China can expect friendship and cooperation … a reckless China can expect vigilance and strength.”7
e.
We would suppose that Communist China is interested in and possibly working on an intercontinental ballistic missile (ICBM) as well as on MRBMs, since an ICBM might be viewed as having political and psychological values from Communist China’s standpoint. We can’t predict when a token ICBM might be demonstrated. It is possible that Communist China might have a few ICBMs by the early 1970’s.
f.
As for our capabilities vis-à-vis the Communist Chinese, we will for the foreseeable future have such a marked superiority that it would be suicidal for them to attempt a nuclear attack on the US. They will have no prospect whatever of mounting a disarming strike against us. We, on the other hand, will continue to possess a vastly larger, much more reliable, and substantially more flexible force. In addition, we could for some years negate any ChiCom nuclear threat to the US, with a light anti-ballistic missile deployment if it should be determined that such a deployment would be desirable.
7.
Has the US considered the effects of ABM deployment on our allies?
a.
We have been giving this matter considerable attention. We have discussed aspects of the ABM question with a number of our allies and anticipate further discussion. To date, such discussions have been very general and have concerned such matters as the status of US ABM development, strategic and other implications of ABM deployment, and arms control aspects.
b.
We have also been undertaking preliminary technical studies of the possible utility of ABMs for defense of other countries. Our purpose has been to obtain a better understanding of potential cost and effectiveness. Our analysis of such basic questions has not yet been completed. [Page 519](FYI. We do not wish to encourage discussion of overseas deployment of ABM at this time. End FYI.)
c.
We plan to keep our allies advised of our plans as we have in the past.
Rusk
  1. Source: National Archives and Records Administration, RG 59, Central Files 1964–66, DEF 1 US. Confidential; Priority. Drafted by Leon Sloss (G/PM) and Wreatham Gathright (S/P); cleared by Secretary Rusk, Sidney Sober (NEA), Samuel D. Berger (EA), Robert J. McCloskey (P), Paul J. Long (ACDA), Frederick D. Sharp (ARA), Foy Kohler (G) in substance, Allen C. Hansen (USIA), Vincent Baker (EUR/RPM), Richard Straus (EUR/CAN), Vladimir Toumanoff (SOV), John T. McNaughton (DOD/ISA), and Alain C. Enthoven (DOD/SA); and approved by Jeffrey C. Kitchen (G/PM). Sent to 43 posts and 4 military commands.

    An undated draft of this airgram was transmitted under cover of a December 21 letter from Kohler to Vance explaining the need for this guidance to posts abroad on “the changes occurring in Soviet and Communist Chinese strategic capabilities and our reactions to them” in order “to avoid a series of incomplete and conflicting statements,” and requesting DOD’s “prompt concurrence or comments” on the airgram. A December 24 note attached to this draft indicates that Vance assigned McNaughton to prepare an alternative version and that Enthoven would supply certain information. (Washington National Records Center, OSD Files: FRC 330 70 A 4443, 471.94 ABM (December) 1966)

  2. Excerpts from McNamara’s statement and responses to subsequent questions at this November 10 news conference in Johnson City, Texas, are printed in American Foreign Policy: Current Documents, 1966, pp. 504–506.
  3. Excerpts from McNamara’s statement and responses to subsequent questions at this December 6 news conference in Austin, Texas, are printed ibid., pp. 506–508. A copy of his full statement released to the press on that occasion is in the Washington National Records Center, OSD Files: FRC 330 71 A 3470, ABM Memo and JCS View Folder 103.
  4. Text in Department of State Bulletin, January 9, 1967, p. 43.
  5. The quotation is from President Johnson’s message of January 21, 1964, to the Eighteen-Nation Disarmament Committee in Geneva. Text in Documents on Disarmament, 1964, p. 8.
  6. President Johnson’s statement on October 16, 1964; text in Public Papers of the Presidents of the United States: Lyndon B. Johnson, 1963–64, p. 1357.
  7. President Johnson’s statement on October 30, 1966; text is ibid., 1966, p. 560.