Foreign Relations of the United States, 1961–1963, Volume VIII, National Security Policy

48. Draft Memorandum From Secretary of Defense McNamara to President Kennedy⁰

Washington, September 30, 1961.

SUBJECT

• Program for Deployment of Nike Zeus

This Appendix summarizes the various factors that were considered in reaching a decision to recommend a program for deployment of Nike Zeus. The Appendix includes the following sections:

I. Summary¹

II. Possible Courses of Action

III. Description, Status, and Technical Evaluation

IV. Reasons for Limited Deployment

V. Growth Capability of Nike Zeus

VI. Planning and Funding for a Limited Deployment²

I. Summary

The question whether the Nike Zeus anti-missile system should be deployed has been under consideration for several years. I have now decided to recommend that funds be included in the FY ’63 budget for Nike Zeus production support. This would make possible its limited deployment in the near future. The Joint Chiefs of Staff support this recommendation.

A recent technical analysis has confirmed that Nike Zeus will not provide soft targets an effective defense against large scale or sophisticated ICBM attacks. A purely technical appraisal would not lead to a recommendation for deployment of a weapon system with so limited an operational effectiveness. This has been the conclusion of past technical evaluations; the current review has revealed no important new technical factors.

On the other hand, the following considerations appear, in my judgment, to favor a limited deployment of Zeus:

a. Although the potential capabilities of sophisticated ICBMs are undisputed, they must be balanced against the expectation that the Soviets will make some errors in the design of their ICBM force and have technical, organizational, and resource difficulties which could limit the capabilities of this force. Our own experience with the development and deployment of ICBM forces has provided examples of such limitations.

b. The existence of a deployed defense may substantially increase the degree of uncertainty at the Soviet decision-making level. The offense will find it more difficult to be certain that weaknesses do not exist which may have been discovered by the defense. Recent evidence indicates that existing warheads on our ballistic missiles are subject to destruction at fairly large distances by nuclear detonations. Though this would not in fact make Nike Zeus effective against planned U.S. missile systems, it is an example of the unpredictable elements involved.

c. In Soviet planning for a military operation, there would have to be some diversion of ICBM forces to penetrate a deployed defense, even though the economic exchange ratio is unfavorable to the defense. This may take the form of extra missiles assigned to saturate, confuse, or destroy anti-missile systems or the introduction of sophisticated reentry vehicles with penetration systems and other protective devices.

d. Even limited deployment would inhibit blackmail from secondary powers, provide some protection against accidental attacks and against violations of arms control agreements.

e. Some counter may be desirable against future Soviet claims to a successful anti-missile system. Soviet efforts in the field of ballistic missile defense appear to be more ambitious than our own efforts. Even if U.S. scientists can offer claims of a U.S. capability to counter completely the USSR defense, this will not cancel out the psychological advantage gained by the USSR in announcing or demonstrating an ICBM defense capability.

f. A system in being may be used as the basis for introducing some improved performance capabilities if target identification proves to be more feasible than is now expected or if reentry vehicle vulnerability is greater than now estimated.

These factors are sufficiently compelling to recommend a limited deployment of the Nike Zeus system. An operational capability can be obtained starting in 1965 and, although other city-defense systems of somewhat greater capability are feasible by about 1970, none of the current proposals provides assurance of a truly effective defense of cities. It should be recognized that deployment of any active city defense (including Nike Zeus) presupposes a system of civilian fall-out shelters.

There is at least one danger in deployment of a defense system of doubtful effectiveness such as Nike Zeus: the Executive Branch of the government, the Congress, and the people may develop an unwarranted faith in its capability to deter a Soviet attack or to mitigate its consequences if full-scale nuclear warfare is initiated.

[Here follow sections II-VI.]

0. Source: Kennedy Library, National Security Files, Departments and Agencies Series, Defense Budget FY 63 1/61-10/61. Secret. This draft memorandum is Appendix II to Document 50, but was circulated in advance of it.
1. Only this section is printed here.
2. This section describes the recommended program of 6 Zeus Defense Centers, each with a Zeus Acquisition Radar, and 12 Nike-Zeus batteries, each with one discrimination radar, 6 target track radars, 12 missile track radars, and 96 missiles. The mission of the system, which would take 6 years to complete installation from the time of a decision to construct it, was to defend 6 cities and “about 39 million people.”