Foreign Relations of the United States, 1977–1980, Volume IV, National Security Policy

55. Memorandum From the President’s Assistant for National Security Affairs (Brzezinski) to President Carter¹

Washington, undated

SUBJECT

• Alternative Ways of Answering the Soviets’ Growing Strategic Counterforce Capabilities

Bill Perry, the DOD Undersecretary for Research and Engineering, recently sent Harold Brown and Charles Duncan a memo on this issue that I thought you might find interesting (Tab A). It provides some information on possible alternatives to putting M–X in silos; a more complete examination of this question is being prepared by DOD in response to your recent request.

In reading the memo, you will note the following points:

— Bill Perry seems quite concerned about the potential crisis instability problem posed by the low survivability of silos.² Nevertheless, he is examining the idea of putting M–X missiles in some of the Minuteman III silos—a seeming contradiction.

— The idea of developing a [less than 1 line not declassified] missile that can also serve as the M–X if we add another missile stage is very interesting. If it is possible, it significantly reduces the risk that a near-term start [less than 1 line not declassified] would end up being wasted effort.

— “Deep silos” means perhaps 1000–2000 ft. below the surface. DOD hasn’t yet identified a good method by which the deep-based missiles might dig themselves out after an attack. Given the delays that might be encountered in digging out, such a scheme might still be useful in providing a long-term reserve force of ICBMs.

— There are a number of “Garwinian” defense schemes for protecting individual silos.³ [2 lines not declassified] The RVs would presumably be destroyed, or caused to detonate at altitudes at which the silo-based missiles would still survive.

Tab A

Memorandum From the Under Secretary of Defense for Research and Engineering (Perry) to Secretary of Defense Brown and the Deputy Secretary of Defense (Duncan)⁴

Washington, March 15, 1978

SUBJECT

• Strategic Deterrence

This is a brief status report on an ongoing analysis we are conducting on alternative ways of maintaining our strategic deterrence in the face of the growing Soviet counterforce capability.

The data available to date on the new guidance systems being tested on the SS–18 and SS–19 suggest that these systems have as their objective significant improvements in accuracy, probably reducing CEP to the dangerous area of 200m to 250m. If they are successful in this area, and if they retrofit this system on deployed SS–18s and SS–19s, they could pose a serious counterforce threat as early as 1983. This is two or three years earlier than we would have estimated if the improved guidance capability had to wait for the next generation of missiles to be deployed. [8 lines not declassified] The latter assumption I think is unrealistic.

Thus our land-based ICBM force not only becomes susceptible to being taken out, it could almost be considered as an invitation to attack. Moreover because we would recognize its susceptibility we would be tempted to launch on warning thereby putting a “hair-trigger” on our deterrence forces. In short, our ICBM force would become destabilizing. For this reason I believe it is urgent that we seriously explore alternatives so that we don’t drift into this situation by the Soviet threat developing before our response was ready.

I am exploring a number of R&D and acquisition alternatives that will provide a timely solution to this problem. Accelerating the M–X is the major alternative but one in which I still have serious concerns because of the technical problems I see and the cost problems I expect to see. We will continue an intensive effort (DRE, AF, and DSB) to develop a technically acceptable MX program. In the meantime, we are pursuing at a conceptual level alternatives to MX. These concepts, if pursued, would entail the following programatic actions:

1. Expedite the TRIDENT II program.

a. The TRIDENT II missile would be accelerated to allow an IOC of 1984.

b. The advanced development phase could be run as a design competition between the TRIDENT contractors and the MX missile contractor(s).

2. Redirect the MX missile program.

a. The MX missile would be a [less than 1 line not declassified] missile plus an additional stage [1 line not declassified]. It would also have a 1984 IOC.

b. [1 paragraph (2 lines) not declassified]

c. [1 paragraph (3 lines) not declassified]

3. Redirect the MX missile basing program.

a. The new MX missile would be put in some of the MM III silos, thus increasing the residual warheads after attack by a factor of three.

b. The balance of the silos would be replaced with deep silos [2 lines not declassified]

4. Consider deployment of a “thin” ABM system.

a. Complete development of the new light-weight non-nuclear interceptor.

b. Install this system for a thin defense of one MM wing [less than 1 line not declassified] with an IOC of 1984. System would include PARS already there plus 100 interceptors (to be compatible with SALT).

c. The deployed system could stop (at most) 100 RVs, but provides a base from which an effective ABM system could be made operational in a year or two from decision.

d. Accelerate R&D in non-conventional (Garwinian) “bloody-nose” defenses of individual silos as a backup to ABM deployment.

5. MM II

a. Left-over MM III missiles could be deployed in MM II silos (compatible with SALT restrictions) during the gap period between POSEIDON phase-out and TRIDENT phase-in. This option may be particularly important if our TRIDENT ship construction problems worsen.

b. Develop a more effective use of our SALT quota of SNDVs than the present MM II.

Some combinations of the programs just outlined would lead to a reduction of ICBM vulnerability by 1984 with high confidence because the technical risks are not high (with the exception of the ABM, which does not seem difficult but involves more unknowns). These programs in aggregate would be less expensive than the MX alternative. The cost of the ABM development is more than offset by the R&D savings effected by a single missile development. The cost of deep silo deployment is more than offset by avoiding the cost of deploying the MX trenches. Also this approach is compatible with present SALT agreements and gives us a good negotiating position for future agreements.

However the concept has a major weakness to the extent it depends upon ABM, as long as we are limited to 100 interceptors. Therefore our major objective continues to be finding a technically sound approach to MX basing. The trench looks less and less attractive and a number of other alternatives are being seriously examined by the Air Force and DSB. I will give you a status report on this effort in a week or two.

William J. Perry

1. Source: Carter Library, National Security Affairs, Brzezinski Material, Subject File, Box 43, Missiles: 3–10/78. Top Secret; Outside the System. Sent for information. In the top right corner of the memorandum, Carter wrote: “Very interesting—J.”
2. See Document 53.
3. Reference is to Dr. Richard L. Garwin, physicist and IBM Fellow at the Thomas J. Watson Research Center in New York. Garwin was a member of the Council on Foreign Relations and an expert on nuclear weapons technology. He was also a member of the Office of Science and Technology Policy panel conducting the Vulnerability Study of the M–X missile. See the attachment to Document 43.
4. Top Secret; Eyes Only. Outside the System. A stamped notation reads: “SecDef has seen.”