16. Paper Prepared in the Arms Control and Disarmament Agency1


A “Stop Where We Are” Proposal for SALT 2

I. Introduction

This paper examines the implications of a quantitative and qualitative freeze on all aspects of strategic offensive and defensive forces that are subject to adequate verification by national means. In view of the extent of our present and projected national intelligence resources, this essentially amounts to a proposal to “Stop Where We Are” (SWWA) with respect to strategic forces.

This proposal is more comprehensive than any of the alternative packages of constraints specifically covered in the NSSM–28 study.3 The detailed examination of the more limited packages considered in NSSM–28 focused attention on the potential advantages of a more comprehensive proposal. More limited proposals tend to deflect the strategic arms race to other permitted channels. Moreover, a more comprehensive approach would improve U.S. security by removing uncertainties associated with various aspects of the more limited proposals.

For example, the SWWA proposal would supplement the most comprehensive NSSM–28 Package IV (MIRV ban) by placing the following additional constraints on potential Soviet developments that could reduce our retaliatory capabilities:

Prohibition on improvements in the throw-weight and accuracy of present ICBM’s and SLBM’s; and
Prohibition on completion of the approximately 300 Soviet ICBM silos and 250 SLBM launchers currently under construction.

The SWWA proposal was not included in the original choice of NSSM–28 packages in an effort to simplify the scope of the study. By [Page 42]the time its full potential advantages were better understood as a result of the NSSM–28 study, it was decided that it was too late to undertake fundamental reorganization of the study to include this proposal, but that it should be studied in parallel as a separate exercise. This paper, therefore, examines the SWWA proposal in the general context of the NSSM–28 study so that it can be available for consideration as an additional possible alternative.

II. Description of “Stop Where We Are” (SWWA) Proposal

In this proposal, the numbers of land-based and sea-based strategic offensive missile launchers would be frozen at present operational levels. Construction would be halted on all launchers which are verifiably not operational. ABM launchers and associated radars would also be frozen at present operational levels. Verifiable strategic offensive and defensive missile and launcher characteristics would also be frozen. For this purpose, all strategic missile flight testing would be prohibited, except for an agreed number of preannounced confidence firings of present types of missiles on agreed ranges. Numbers and external characteristics of strategic bombers and air-defense missile launchers would also be frozen at present levels. (A more precise description of the SWWA proposal and several possible variants appears at Tab A.)4

III. Rationale for SWWA Proposal

A SWWA agreement would preserve the present stable strategic balance, in which both sides have a confident second-strike capability and are far from achieving a first-strike capability. While the Package IV MIRV ban with a low ceiling on ABM levels would reduce the most imminent threats to this stability, the additional provisions of SWWA would block other destabilizing potential future developments and would minimize arms procurement pressures arising from uncertainties as to how an adversary might choose to utilize loopholes and hedges available under an agreement. More specifically, a SWWA arms control agreement would have the following implications:

A SWWA agreement would virtually eliminate the potential Soviet counterforce threat against the U.S. Minuteman force by preventing substantial improvements in missile throw-weight and accuracy. A MIRV ban (Package IV) would help to delay this potential Soviet threat but would not eliminate it, since the Soviets would still be able, sooner or later, to improve the accuracy and throw-weight of all their offensive strategic missiles. Although U.S. SLBM’s and bombers would still have a large retaliatory capability, this path of development could permit the Soviets eventually to attain a capability to destroy most of the [Page 43]undefended U.S. Minuteman ICBM force as it is now constituted. A SWWA agreement, however, would effectively prevent the Soviets from making significant improvements in the throw-weight of their ICBM’s. It would also preclude their testing, and hence deployment, of a new generation of less-blunt reentry vehicles which are necessary to achieve high accuracy. For reasons explained below, this restriction would prevent the Soviet Union from improving their large force of SS–11’s to have sufficient accuracy to threaten the bulk of the U.S. Minuteman force.
By prohibiting missile flight-testing (other than confidence-firing of present types), SWWA would improve our confidence that the Soviets were not developing MIRV’s or other missile improvements. It is highly unlikely that any nation would deploy a major new strategic weapon system which it could not flight-test, and even more unlikely that it would have the confidence to rely on such an untested weapon system for a counterforce first-strike. Thus, the verifiability of any agreement limiting missile characteristics is directly related to the degree that flight tests of improved systems can be restricted. Our ability to detect any illegal testing would be enhanced by our being able to focus our national means on the limited number of pre-announced confidence-firings and the space shots. Furthermore, diversion of a significant number of the limited quota of permitted confidence-firings in any attempt at illegal developmental flight tests would necessarily reduce the Soviets’confidence in the reliability of their deployed, permitted missile systems.
The Soviet Union now has approximately 300 ICBM silos and 250 SLBM launchers under construction. A SWWA agreement would prevent the Soviets from completing these launchers; such completion would increase the total Soviet strategic offensive missile force by about 45 percent.
Freezing the number and verifiable characteristics of SAM systems would increase our confidence that existing Soviet SAM’s would not be clandestinely improved to acquire an ABM capability and would preclude the possibility that new SAM systems with a possible dual ABM capability might be introduced. If SAM’s are frozen, a strategic bomber freeze would also appear desirable to the U.S. since the U.S. now has a major quantitative and qualitative lead over the Soviet Union in strategic bombers—an advantage that it is in our interest to maintain. There may, however, be some difficulty in negotiating mutually satisfactory definitions of such terms as “strategic bomber” and “external characteristics”.
A SWWA agreement would prevent both sides from building a strategically significant ABM system, but under such an agreement neither side would need an ABM system to defend its ICBM force. Conversely, the assurance that ABM levels will be kept very low removes both sides’ incentive to deploy MIRV’s. A variant to the basic SWWA [Page 44]proposal which would permit a small U.S. ABM system against Chinese or accidental attacks, could be considered.
It is difficult to predict what the Soviet reaction to a SWWA proposal might be. While SWWA favors the U.S. in terms of the strategic balance, it might appeal to Soviet desires to ease their economic burdens.
While a SWWA agreement would preserve the present U.S. lead in numbers and characteristics of most strategic weapon systems, it would preclude many U.S. plans and options to improve these systems. We would, however, still be able to carry out a number of hedges or safeguards for those threats the SWWA agreement did not remove, including the threats of abrogation or evasion of the agreement. For example, we could very effectively hedge against any clandestine ABM deployments by developing improved exoatmospheric penetration aids and by further hardening of ICBM and SLBM reentry vehicles. As a further example, we would improve the reliability of our missiles and reduce their vulnerability to a variety of threats such as nuclear pindown.
If a SWWA agreement were abrogated, and the USSR had kept its ABM or MIRV production facilities in a higher readiness state than did the U.S., the Soviets might be able to improve their relative strategic posture to some extent, at least temporarily.
A SWWA agreement should provide the U.S. with far greater budgetary savings, both short-term and long-term, than any alternative which permits substantial new strategic weapons programs. If such an agreement were reached this year, FY–71 savings alone could amount to as much as $5 billion.

IV. Verification

The CIA estimates that a SWWA agreement could be verified with high confidence (see Tab B).5 Because all strategic systems would be constrained under SWWA, there would theoretically be a broad spectrum of possible types of violations. The verification task, however, would in fact be eased considerably in many respects under SWWA, since detecting changes in Soviet deployments or tests would be much easier than distinguishing between the permitted and prohibited changes that would be involved under the other packages. For example, in monitoring flight tests, we would only have to watch for departures from the well-documented signatures of present Soviet missiles; we would not need to try to deduce the purpose of a new test program, which might be accompanied by efforts at concealment and deception from its very beginning. Furthermore, the limitation on the number of flight tests, in addition to presenting the potential violator [Page 45]with the formidable problems mentioned earlier, would ease the problems faced by the verifier. The significantly smaller number of preannounced tests on agreed ranges would allow considerable focusing of U.S. intelligence collection and analysis capabilities.

Our capabilities to verify the significant new provisions of SWWA deserve special attention:

The restrictions on flight testing can be monitored with our present collection capabilities if Soviet tests are carried out at existing test ranges. Were the Soviets to attempt such tests at new and remote launch facilities today, we could not assure detection of shorter range tests. We are confident, however, that no unidentified flight-test ranges exist or are under construction in the Soviet Union, and we would probably become aware of them within a very few months if such construction were started. By the time a new test range attained operational status, our planned collection sources would provide high-confidence assessments of the activity involved. In any event, our planned systems would give high confidence of detection of any unannounced strategic missile launchings.
[1 paragraph (6 lines) not declassified]
[1 paragraph (17 lines) not declassified]
Freezing the number and verifiable characteristics of SAM systems would increase our confidence that Soviet SAM’s would not be clandestinely improved to acquire an ABM capability or that new dual-purpose systems might be deployed.
While the need to detect land-mobile missiles and possible retrofitting of ICBM’s at IRBM launchers exists under all the alternative packages, the SWWA constraints on testing would somewhat reduce the difficulties of these tasks.

V. Strategic Analysis

A. Strategic Exchange Calculations

Strategic exchange calculations were carried out to determine retaliatory capabilities of U.S. and Soviet forces under this agreement. Assumptions regarding scenarios, alert rates, reliabilities, effectiveness of penetration aids, etc., were consistent with those used in the NSSM–28 report. Detailed listings of U.S. and Soviet force levels and characteristics assumed are given at Tab C.6 It should be noted that we assumed modest improvements in the CEP’s of Soviet ICBM’s and SLBM’s in spite of the fact that efforts to achieve such improvements would be contrary to the agreement. It was assumed that neither side relied upon pen-aids in either first or second strikes.

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1. Deterrence

Table I shows the retaliatory capability of the U.S. and USSR under SWWA and under Packages III and IV.

Table I
Retaliatory Capability in 1978

Percent Soviet Fatalities Percent U.S. Fatalities
Option III (0 ABM) 40 43
Option IV (0 ABM) 38 54
SWWA 42 45

If both sides had 500 area ABM’s or a Safeguard ABM system, the U.S. retaliatory capability would drop to about 37 percent Soviet fatalities and Soviet retaliatory capability would be slightly less. A fall-back from SWWA that allowed the Soviets to complete all ICBM and SLBM launchers now under construction would cause a decrease of less than 1% in U.S. retaliatory capabilities and would improve slightly the Soviets’retaliatory capabilities.

2. Damage Limiting

Under SWWA neither side would have any incentive to strike first, since both would incur over 125 million fatalities in retaliation from a preemptive attack on the opponent. Essentially, SWWA preserves the damage-limiting capabilities of both sides at their present levels and thereby inhibits either from attempting to achieve a credible first-strike capability.

3. Survivability of U.S. Strategic Forces

One of the most striking effects of SWWA is the greatly enhanced survivability of our present ICBM force compared to the other packages as shown in Table II.

Table II
Percent of Land-Based ICBM’s
Surviving a First Strike (1978)

U.S. Soviet
Package III 4 24
Package III with hard-rock silos 25 77
Package IV 30 62
SWWA 79 71

These figures assume that there is no ABM protection for ICBM’s. For comparison, in Package III with an ABM defense consisting of 500 [Page 47]area interceptors and 2000 hard-point interceptors, only about half the U.S. ICBM force would survive.

The reason for the greater survivability of U.S. ICBM’s under this package is the absence of Soviet MIRV’s and the restrictions on significant improvements in the accuracy and throw-weights of Soviet ICBM’s, particularly the SS–11 and its follow-on missile. Some people have urged that a limitation on throw-weights alone should be a part of an agreement. While this would serve to lessen the Soviet counter-force threat somewhat, it would not do so sufficiently unless the development of high accuracies was also restricted, since accuracy is a more significant parameter in determining counterforce capability. The SS–9 is now a potentially effective counterforce weapon, but there are less than 200 currently operational. The numerous SS–11’s, on the other hand, already possess the throw-weight needed to become a counter-force threat if CEP’s on the order of 0.25 nm. are achieved. The Intelligence Community estimates that such accuracies are within future Soviet capabilities, but that they would require significant improvements in guidance and RV characteristics. SWWA is the only proposed approach which would preclude such improvements.

The high survivability of the U.S. ICBM force under SWWA would mean that U.S. retaliatory capabilities could be maintained without reliance upon missile penetration aids or bombers for ABM levels up to about 1,000 interceptors. In fact, under SWWA at present ABM levels, ICBM’s alone could kill 35 percent of the Soviet population after absorbing a Soviet first strike.

Finally, the survivability of U.S. bombers could also be improved because of the truncating of the Soviet SLBM program.

4. Sensitivity to Soviet Violations

Under such a comprehensive measure, the question of cheating must be considered carefully, since one might expect that the sensitivity to cheating would be greater than under less restrictive measures. However, it must be recognized that cheating would be much more difficult to carry out successfully under a comprehensive measure as discussed in Section IV above.

We have examined the case in which the Soviets violate the agreement by adding 300 ICBM’s to their force (SS–9’s and SS–11’s)7 and found that the U.S. retaliatory capability remains above 40%. We also examined the case in which the Soviets violate the Basic SWWA Agreement [Page 48]by adding 500 area ABM interceptors. In this event, the U.S. retaliatory capability would drop to 35 percent (26 percent with ICBM’s alone).

VI. Safeguards

Since one of the purposes of SWWA would be to reduce Soviet options for increasing their strategic capabilities, it is not surprising that the number of hedges available to the U.S. would also be less than under other measures. Nevertheless, several important hedges would still be available to us, such as the following:



The SWWA freeze would leave the U.S. with a lead in MIRV technology. MIRV production lines could be kept available on a standby basis. In the event the Soviets cheated on ABM restrictions, the U.S. probably could deploy MIRV’s for ABM penetration with little or no further flight testing, depending upon when the agreement took effect. Such deployments could be made fairly rapidly on Minuteman. Poseidon retrofits would take considerably longer because of the extensive launcher modifications required.


penetration aids

Improved exo-atmospheric penetration aids could be tested and deployed. This would be sufficient to give us high confidence that we could penetrate an area ABM defense or an SAM air-defense system which had been upgraded for point-in-space RV intercepts.


Increased Missile Hardening

Missile guidance systems and reentry vehicles could be further hardened so long as external characteristics remained unchanged. This would be a hedge against both ABM cheating and possible pindown counterforce attacks.



The number of strategic bombers currently deployed could be maintained rather than cut in half as now planned. Bomber alert rates could be increased, and bombers could be dispersed to additional bases. Bomber performance and armament could be improved, as long as the external appearance of the bomber remained the same.

VII. Negotiability

Little is known of Soviet views concerning the preferred scope of a strategic arms limitation agreement. On balance, we believe that the Soviets would probably favor a simply defined agreement with broad application and would tend to be suspicious of any significant loopholes which the U.S. wanted to keep open.

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Chairman Kosygin told Robert McNamara on November 11, 1968, that it would be absurd for the two superpowers to continue to accumulate strategic armaments. “Both sides have enough”, he said.8 While this statement probably should not be interpreted too literally, it does seem plausible that a relatively simply agreement to “stop where we are” may be easier to negotiate than one with loopholes which permit significant new strategic weapon developments by either side.

If, as seems likely, the Soviets hope to achieve some easing of the economic burdens of the strategic arms race through SALT, they would have an additional incentive for favoring an agreement like SWWA (see Section VIII).

VIII. Economic Implications

NSSM–28 estimates the annual cost of Packages I–IV during FY 70–74 at $15.5 billion. Implementation of certain “safeguards” permitted under these packages could cost an additional $3.3 billion annually, raising the total annual cost to $18.8 billion.

Under SWWA, the estimated annual cost during this period would be $13.9 to $14.4 billion, thereby saving a total of $4.4 to $4.9 billion per year. The total five-year savings would be approximately $22 to $25 billion.

IX. Moratorium During Negotiations

Some of the advantages of a SWWA agreement to the U.S. would be reduced if the Soviets continued to build ICBM silos and SLBM submarines and carry on MRV or MIRV flight testing during the SALT negotiations. The Soviet Union is currently building about 250 ICBM launchers and 100 SLBM launchers per year, [1½ lines not declassified].

Therefore, the U.S. may wish to propose, early in the negotiations, a temporary moratorium on construction of strategic missile launchers and on certain types of flight testing during the SALT negotiations. In addition to providing an earlier halt to Soviet strategic missile launcher construction and MRV testing, such a moratorium would have the added advantage of minimizing Soviet incentives to prolong the negotiations in order to improve their strategic position.

  1. Source: Ford Library, Laird Papers, Box 22, SALT, Chronological File. Top Secret. Smith sent this paper to Packard under cover of a June 12 memorandum. He also sent Kissinger a copy on June 12. (National Archives, Nixon Presidential Materials, NSC Files, Box 873, SALT, Volume II, June–July 1969)
  2. In his memoirs, Smith summarized this proposal: “My MIRV ban proposals soon merged into a broader position called SWWA, ‘Stop Where We Are,’ which involved not only stopping MIRV testing but cessation of Soviet ICBM and SLBM launcher construction programs.[…] SWWA was based on a simple concept that the way to stop arms competition was to stop strategic construction programs on both sides.” (Smith, Doubletalk, p. 160)
  3. See Document 14.
  4. Attached but not printed.
  5. Attached but not printed.
  6. Attached but not printed.
  7. The SS–9 and SS–11 were Soviet ICBMs. The high accuracy and yield of the SS–9 made it a threat to U.S. ICBMs. The SS–11 was the Soviet counterpart to the U.S. Minuteman system in quantity, size, and purpose. It was believed to be effective only against soft targets.
  8. See Foreign Relations, 1964–1968, volume XIV, Soviet Union, Document 314.