Foreign Relations of the United States, 1964–1968, Volume X, National Security Policy

221. National Intelligence Estimate¹

NIE 11–3–68

Washington, October 31, 1968.

SOVIET STRATEGIC AIR AND MISSILE DEFENSES

The Problem

To estimate the strength and capabilities of Soviet strategic air and missile defense forces through mid-1970, and general trends in these forces through 1978.²

Conclusions

A. Throughout the postwar period the USSR has devoted a major effort to strategic defense. This effort can be attributed primarily to the size and diversity of US strategic attack forces, although for the future the Soviets must consider the threat posed by third countries, particularly China.

B. We believe that the competition for resources in the USSR is likely to intensify, not only between civilian and military programs, but also within the military establishment. These pressures may exercise a restraining influence on the strategic defense effort, but are unlikely to reduce it below present levels. The trend for the longer term will depend heavily upon Soviet decisions concerning antiballistic missile (ABM) deployment and the related question of strategic arms control.

C. The Soviets have built a formidable system of air defenses, deployed in depth, which would be very effective against subsonic and low-supersonic aircraft attempting to penetrate at medium and high altitudes. The system is less effective against higher performance aircraft and standoff weapons; it has virtually no capability against low-altitude penetration below about 1,000 feet except in a few, limited areas. The Soviets recognize these shortcomings and are deploying new interceptors, surface-to-air missiles (SAMs), and radars in an effort to overcome them.

D. At present, the major effort is directed to counter the threat posed by high-performance aircraft and standoff weapons. Deployment of the SA–5 long-range SAM system is the largest single defensive weapon program now underway. This system represents a considerable improvement over older systems in terms of range, velocity, and firepower. It is being deployed as a barrier defense around the European USSR and for point defense of selected targets. We estimate that there are some 60 SA–5 complexes, and that nearly half are operational; we believe that some 100 complexes will be operational by 1973. The Soviets have also been testing an airborne warning and control system (AWACS) that will probably enter service soon. This system, deployed in coastal areas and used with long-range interceptors, could greatly extend the area in which incoming aircraft could be engaged.

E. The Soviets are also attempting to strengthen their air defenses against low-altitude attack, but their efforts of the past year have resulted in minor improvements rather than in any fundamental solution to the problem. They have deployed all-weather interceptors with improved capabilities for low-altitude attack, and they will probably introduce more advanced SAMs and interceptors better suited for low-altitude defense. The primary limitation on low-altitude defense, however, is surveillance and control. Deployment of new radars has improved tracking capabilities in limited areas down to altitudes of 500 feet and even below, but we expect little advance in ground-based continuous tracking capability at low altitudes during the period of this estimate.

F. The Moscow ABM system (ABM-1), under deployment since 1962, has probably achieved some operational capability. Its deployment has apparently been cut back substantially from the originally planned level; the elements still under construction will probably be operational in 1970. We believe that the Soviets plan additional deployment of an improved ABM system at Moscow. ABM development continues, but we cannot determine whether it involves an improved version of the Moscow system or a substantially improved, second-generation ABM system, although we consider the latter more likely. We still do not believe that there is any deployment of ABM defenses outside the Moscow area. We believe that the SA–5 long-range SAM system is unlikely to have a present ABM capability, although the state of available evidence does not permit us to exclude this possibility, and we consider it unlikely that it will be modified for an ABM role.³

G. Deployment of ABM defenses beyond Moscow will probably await the availability of a second-generation system. If such a system is now under development, it could reach an initial operational capability in the 1973–1975 period; like the Moscow system, it will probably be designed for long range, exoatmospheric intercept. The extent of future deployment will depend heavily upon economic as well as technical considerations. Deployment of a national defense system on a scale sufficient to cope with the full US missile threat does not appear to be a feasible course of action for the USSR within the period of this estimate. We believe that the Soviets will decide upon a program that would provide some defense for the most important target areas in the USSR. Some part of this defense would probably be deployed against Communist China and other third country threats.

H. We have no evidence of a Soviet antisatellite weapons program nor of Soviet development of hardware specifically for this purpose. It would be technically possible, however, for the Soviets now to have a limited antisatellite capability. With existing radars and missiles armed with nuclear warheads, they could almost certainly destroy or neutralize current US satellites up to about 2,000 n.m. during an early phase of their mission. With terminal homing in the interceptor missile, they may even be able to neutralize satellites using a nonnuclear warhead. Soviet technical capabilities are such that they could develop and deploy during the next 10 years any of several types of antisatellite systems if they chose to do so. We believe, however, that the Soviets would realize that any use of antisatellite systems in peacetime would expose their own satellites to attack, and consider it unlikely that they would do so except in retaliation.

Discussion

I. Soviet Strategic Defense Policy

1. Soviet strategic defense forces have gone through several stages of development since World War II. Through the mid-1950’s the Soviets attempted to counter the large US strategic bomber force in being with large numbers of air surveillance radars and interceptor aircraft, reinforced at Moscow with large numbers of surface-to-air missiles (SAMs). As the US force obtained higher performance intercontinental bombers, the Soviets in the late 1950’s developed and deployed Mach 2 interceptors and extended SAM defenses throughout the country. When the US, in the face of this extensive defense, began practicing low-altitude penetration tactics, the Soviets began in the early 1960’s deploying the Firebar interceptor and the SA–3, both possessing better capabilities for low-altitude intercept than earlier systems. The US deployment of a standoff capability with air-to-surface missiles (ASMs), was followed by Soviet development and the current deployment of the Fiddler interceptor and the SA–5 system, which have greater ranges than earlier systems.

2. In their efforts to have a defense in being against an immediate threat, the Soviets have generally deployed a system quite early in the development cycle, using available technology, rather than wait for the development of more advanced but unproven techniques. These systems have then generally been modified and improved during the period of deployment. In some cases, however, deployment has been canceled early in the program either because the system proved relatively ineffective or because a better one was in the offing. When an improved system has been deployed, older ones are not rapidly retired or replaced. The Soviets tend to have extensive defenses deployed in depth, usually with considerable redundancy. This redundancy may give the defenses as a whole a greater capability than analysis of each weapon system alone would indicate. On the other hand, some elements of the defenses are always somewhat out of date, and do not represent the most effective Soviet counter to new US systems or concepts of operation.

3. Soviet military planners probably see the US strategic threat in the mid-1970’s as consisting of three major forces: bombers and ASMs, intercontinental ballistic missiles (ICBMs), and submarine-launched ballistic missiles (SLBMs). They are aware that the threat will become more sophisticated and formidable with the incorporation of improvements—new aircraft, ASMs, aerodynamic and ballistic penetration aids, and multiple independently-targeted reentry vehicles (MIRVs). The weight of a US attack could be increased by the strategic forces of Britain and France; the Soviets probably view the British forces as simply adding to the Polaris threat, but French intermediate-range ballistic missile (IRBM) deployment will pose a threat from a new quarter.

4. The Soviets probably believe that the massive air defense forces they have built and are building will provide an effective counter to the medium and high-altitude bomber threat, although they realize the problem of low-altitude defense is not yet satisfactorily solved. The most critical requirement of Soviet strategic defense, and the one most difficult to meet despite more than a decade of effort, however, is defense against ballistic missiles. The nature and extent of antiballistic missile (ABM) deployment is almost certainly one of the major questions of Soviet military policy.

5. For the period of this estimate, the US and its allies will continue to pose the principal strategic threat to the USSR, but Soviet military planners must also be concerned with the emerging strategic capabilities of a hostile China. The substantial military buildup along the Chinese border over the past few years has consisted primarily of theater forces. The strengthening of air defenses has been modest in comparison, and at a deliberate pace that in the Soviet view probably matches Chinese offensive capabilities. The Soviets almost certainly believe that their great superiority in offensive strategic weapons will enable them to cope with any threat that might materialize in the foreseeable future, and they hope for a political change in China that would remove this possibility. For the longer term, however, Moscow must consider the problem of ABM defenses against a new threat from the south.

6. Soviet decisions as to how best to meet the strategic threat of the mid-1970’s will be affected not only by the Soviet view of the threat and the pace of technological development, but also by the constraints of economics. The present Soviet leadership has shown a general disposition to accommodate military programs, and military expenditures have continued to rise. Moreover, within the military establishment strategic defense has long enjoyed a favored position. We estimate that the Soviet strategic defense effort is larger, both in absolute terms and as a share of the total military budget, than that of the US. Developments of the past year, however, have strengthened the demands of competing claimants, both civilian and military. The Soviet leaders have shown rising concern over the adverse effects of military spending upon economic growth; we believe that this was a major consideration in their decision to discuss strategic arms control with the US. Now the Czech crisis has raised new requirements for theater forces in Europe which, together with the continuing buildup on the Chinese border, will probably bring a significant increase in Soviet theater forces. Thus, we believe that competition is likely to intensify, not only between civilian and military programs, but also within the military establishment.

7. Current pressures may exercise a restraining influence on the strategic defense effort, but are unlikely to reduce it. For the near term, at least, expenditures for strategic defense will probably be maintained at their present high level, while military expenditures as a whole continue to rise. The trend for the longer term will depend heavily upon Soviet decisions concerning ABM deployment—potentially the most costly single military program on the horizon—and the related question of strategic arms control. If the Soviets embark upon any sizable new program of ABM deployment within the next few years, expenditures for strategic defense will increase and by the middle 1970’s are likely to exceed those for strategic attack by a substantial margin.

[Here follow Parts II–V and three tables (pages 6–29).]

1. Source: Johnson Library, National Security File, Intelligence File, Miscellaneous CIA Intelligence Memoranda [4 of 4], Box 14. Top Secret; [classification marking not declassified]; Controlled Dissem. A cover sheet, title page, prefatory note, and a table of contents are not printed. According to the prefatory note, the CIA and the intelligence organizations of the Departments of State and Defense, the Atomic Energy Commission, and the National Security Agency participated in the preparation of this estimate. The representatives of the CIA, State Department, DIA, NSA, and AEC concurred; the FBI representative abstained, the subject being outside his jurisdiction.
2. This estimate considers only those Soviet strategic defensive forces located in the USSR and Eastern Europe. The Soviet antisubmarine warfare effort, with its implications for Polaris, will be discussed in the forthcoming NIE 11–14–68, “Soviet and East European General Purpose Forces.” [Footnote in the source text. NIE 11–14–68 is in the National Archives and Records Administration, RG 263.]
3. For the views of Maj. Gen. Jack E. Thomas, the Assistant Chief of Staff, Intelligence, USAF, and Maj. Gen. Joseph A. McChristian, the Assistant Chief of Staff for Intelligence, Department of the Army, on the mission and capabilities of the SA–5 (Tallinn) system, see their footnote on page 17. [Footnote in the source text.]