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

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

Washington, October 25, 1978

SUBJECT

• The Triad and Its Alternatives

Harold Brown has sent you an information memo responding to your questions in the recent Mid-Term Defense Review meeting about the need to maintain a full Triad of strategic forces.²

Harold argues that while various combinations of SLBMs, bombers and novel ICBM deployment schemes or M–X/MAP can give us roughly equal cost Dyads or Triads that will equally well maintain an overall balance with the Soviets in terms of the usual static measures and dynamic exchange calculations, by going to a posture without M–X/MAP, we will give up features of the ICBM force that have substantial perceptual and military value.

Harold specifically suggests that allowing the Soviets to pressure us into giving up the military advantages of an ICBM force while they retain them would have a “disastrous effect” on both international and domestic perceptions. The military capabilities we would sacrifice to at least some degree are: independence from tactical warning; endurance after an initial exchange; quick response hard-target kill capability; good C3; and warfighting capability—which is the ability to use limited amounts of strategic forces against particular numbers and types of targets selected on the basis of how a nuclear war unfolds.

Harold also comments on the value of diversity in strategic forces, particularly as a hedge against the unexpected, and presents a short discussion of problems he sees with four alternative missile deployment schemes (air-mobile, ground-mobile, air-launched, and offshore submersible).

Overall, the memo makes a forceful case for modernizing our strategic force posture with M–X/MAP. In so doing it raises a number of interesting and difficult issues that should be more fully illuminated. Specifically:

Harold is imposing requirements on our strategic force posture, [2 lines not declassified]—which they don’t now meet and which have never really been imposed on them before. While imposing these requirements may very well be justified, we should first examine the doctrinal issues that give rise to such needs and which have been addressed in the very nearly complete PD–18 follow-on targeting study. We should also examine the potential for improvements in the capabilities of other forces to meet these same requirements. For example, SLBM C3 can be probably improved enough to allow large-scale SLBM strikes against time-sensitive targets under worst case conditions.

The stated requirement for capabilities to destroy targets rapidly seems to drive much of the argument in favor of an ICBM force. Harold should be asked for descriptions of the various classes of time-sensitive targets including numbers of each type, their relative day-to-day and minimum values, and the time the Soviets would need to reduce them to their minimum values. Further, since the large majority of the time-urgent hard targets are Soviet silos, launch control centers, and their associated C3 systems, it would be useful to ask Harold and Stan Turner to assess the likelihood that even if we did have an extensive time-urgent hard target kill capability we could prevent launch of a significant fraction of the Soviets’ ICBMs.

I wonder if we aren’t being a little over-selective in choosing where to mimic the Soviets and where not to. In particular, why must we match their land-based ICBM capabilities, but not the [less than 1 line not declassified] strategy that their exercises suggest they might adopt in times of crisis? Soviet exercises and doctrine give us reason to believe that strategic warfare is very unlikely to grow out of situations in which you will not have had hours or even days to implement a crisis-only [less than 1 line not declassified] strategy and contemplate your response if and when tactical warning of an attack comes in. We should also consider the possibility that in order to deprive us of strategic warning, the Soviets would have to leave themselves significantly more vulnerable to a retaliatory response. It seems clear that we need a better understanding of Soviet thinking and capabilities for [less than 1 line not declassified]

The memo’s summary of difficulties and deficiencies of the alternatives to M–X/MAP seems a little hasty. We can afford to look at these possibilities more carefully, particularly if we keep our options open by proceeding with a common missile that could be used in Trident or in any of the ICBM deployment schemes, including MAP.

The arguments given in favor of M–X/MAP assume the Soviets will not respond by fractionating their missile payloads significantly above current projections. Even within the limits of the current SALT proposals, they can fractionate enough to sharply raise MAP’s costs and the land area it would require. How should we view this possibility?

Harold’s memo does not explicitly mention an argument for the Triad frequently made, i.e., that ICBMs protect the bombers by making it very difficult for the Soviets to attack both. Does modernization of ICBMs provide any such benefit to bomber survivability or does retention of some Minuteman in silos provide this benefit?

The issue of hedging against both evolving and unforeseen Soviet threats raises an interesting question. Is the margin of advantage of a Triad over a Dyad in hedging against unforeseen threats that meaningful if the ICBM modernization schemes required to maintain a Triad must be maintained against evolutionary expansions of threats we can already see?

The argument that abandoning the ICBM field to the Soviets could have a disastrous effect on perceptions needs more development. Are we being run unilaterally out of an otherwise attractive force posture, or are we simply the first to recognize and respond to a problem of technological obsolescence that the Soviets will eventually have to face?

Finally, there are several larger issues that this discussion of Triads versus Dyads does not come to grips with. Specifically, as we enter the relatively dangerous early 80’s, we should have a clear view of what we need in terms of specific strategic capabilities, that may be realized in a variety of different forms, and how the Soviets may try to respond to our modernization efforts. We should ask which force mix poses the greatest problem over the course of a protracted competition to the Soviet force planner concentrating on damage-limiting objectives:

— Augmented sea and air mobile forces with no ICBMs?

— Augmented sea and air mobile forces with some silo-based ICBMs?

— Augmented sea and air mobile forces with improved and rebased ICBMs?

A better understanding of these larger issues may strongly influence our answers to the current key question—are the strategic capabilities we add or retain by modernizing and rebasing ICBMs really unique and necessary?

1. Source: Carter Library, National Security Affairs, Brzezinski Material, Brzezinski Office File, Subject Chron File, Box 89, Doctrine/C3I: 1978. Top Secret; Sensitive. Sent for information. The date is handwritten. Carter initialed the upper right corner of the memorandum.
2. See Document 97.