Foreign Relations of the United States, 1981–1988, Volume XLIV, Part 1, National Security Policy, 1985–1988

248. Letter From the Chairman of the Joint Chiefs of Staff (Crowe) to Senator Nunn¹

Washington, January 15, 1988

Dear Mr. Chairman,

I am pleased to provide my assessment of the military consequences of eliminating US and USSR strategic ballistic missiles. As specified in the Department of Defense Authorization Act, both classified and unclassified reports are attached.²

As stated in the reports, an arms control agreement eliminating US and USSR strategic ballistic missiles would have substantial repercussions on the essence of deterrence and the future force structure of the United States. Without spending levels above current projections, the United States could not make such a transition and keep risk relatively constant to that which exists today.

The other members of the Joint Chiefs of Staff agree with my assessment.

Without Appendix A, this letter is unclassified.

Sincerely,

William J. Crowe, Jr.
Chairman
Joint Chiefs of Staff

Appendix A

Report Prepared in the Joint Chiefs of Staff³

Washington, undated

REPORT TO CONGRESS ON THE MILITARY CONSEQUENCES OF ELIMINATING US AND USSR STRATEGIC BALLISTIC MISSILES (U)

1. (U) Introduction

a. (U) This classified report presents the views of the Chairman, Joint Chiefs of Staff, on the military consequences of eliminating all US and USSR strategic ballistic missiles. The report has been prepared in response to the National Defense Authorization Act for Fiscal Years 1988 and 1989, Section 905, which requires “the Chairman of the Joint Chiefs of Staff shall submit to the Committees on Armed Services of the Senate and House of Representatives a report examining the military consequences of any arms control agreement between the United States and the Soviet Union that would provide for the elimination of all strategic ballistic missiles of the United States and the Soviet Union.” This report and a companion unclassified version include a discussion of the strategic, budgetary, and force structure implications of eliminating US and USSR strategic ballistic missiles.

b. (U) The summary finding of this report is that a safe US force structure transition to a world without strategic ballistic missiles could not be undertaken without spending levels above current projections. Although significant additional funding might allow the United States to transition safely to the elimination of strategic ballistic missiles, there are no assurances that the Soviets would ever accept such a reduction. In fact, the likelihood of the Soviets accepting such a proposal would be relatively low because it would eliminate strategic ballistic missiles which form the core of their national defense strategy, capability, and international prestige.

2. (U) Background

a. (S)(NOFORN) Threat. If the Soviets agreed to eliminate strategic ballistic missiles, they would make significant adjustments to their other strategic offensive forces. They probably would build many more bombers carrying air-launched cruise missiles and bombs, and place additional sea-launched cruise missiles on submarines. In addition, to counter the remaining US air breathing threat, the Soviets would likely increase the size of their interceptor and SAM air defense forces by some 20 to 25 percent. It is difficult to assess how an agreement might affect already powerful Soviet conventional forces. Such a prediction would depend on the significance the Soviets placed on strategic force changes and their perception of the overall balance once ballistic missiles disappeared. The costs of changing their strategic forces make it unknown whether the Soviets would be willing to apply the resources to improve their conventional forces beyond the formidable level already planned. However, we could very well see accelerated additions of low-strength motorized rifle and tank divisions in the western USSR as well as theater air defense improvements. Presuming a Soviet transition from SSBNs to SLCM submarines in the strategic arsenals, they could place increased emphasis on their capability to defend against US SLCM submarines, attack the SLOCs, or protect Soviet forward-deployed or bastion-deployed SLCM submarines.

b. (S)(NOFORN) Deterrence. The basis for US nuclear deterrence would not change with the elimination of strategic ballistic missiles. In order to deter belligerent Soviet actions against the United States and its allies, the United States would have to remain capable of denying Soviet war aims by destroying with nuclear weapons what the Soviets hold most dear. In spite of eliminating strategic ballistic missiles, the Soviet target base the United States would have to strike to achieve that objective would remain substantial because Soviet ballistic missiles comprise less than 15 percent of that target base. Although the ratio of nuclear weapons on each side would improve arithmetically for the United States if strategic ballistic missiles were eliminated, the United States would still have fewer weapons per target than we believe the Soviets would have for their target base. Also, the total number of US weapons required to hold the adjusted Soviet target base at risk would not change appreciably. On the other hand, the fundamental structure of US deterrent forces would be altered as the United States shifted to some other form than the classic strategic Triad. In transitioning to an alternative future without strategic ballistic missiles, one could not simply assume that replacing ballistic missile warheads with, for example, bomber- or SLCM-delivered warheads would maintain a deterrent posture equal to that of today. The composition and capabilities of the forces would be too different to justify such an assumption without more information on both nation’s residual strategic posture. On the other hand, eliminating strategic ballistic missiles and the attendant restructuring of strategic forces to bombers and SLCM submarines could lead to increased deterrence favoring the United States which is much better equipped—by history, training, and culture—to wage bomber and submarine warfare than the Soviets. Moreover, without the threat of Soviet strategic ballistic missiles (nuclear or conventional), a Soviet surprise attack against key NATO facilities would be less effective—although in the United States key installations near each coast would still be vulnerable to short-warning SLCM attacks. Strategic defenses in such an environment would become more important to the United States because that capability is now skewed in favor of the Soviets—the United States has virtually no strategic air defense and no ABM defense at all. Greatly enhanced, damage-limiting air defenses, coupled with strategic offensive, defensive, and nonstrategic nuclear force improvements, could raise Soviet uncertainty and lead to increased deterrence. The impact of these contrasting views about the efficacy of nuclear deterrence on conventional deterrence is uncertain and would depend primarily on how the Soviets might perceive the willingness of the United States and its allies to escalate in response to a Soviet provocation. Clearly, the United States and its allies would have to demonstrate that willingness by maintaining relevant, undisputable capabilities for flexible response despite the changed environment of strategic arms.

3. (U) Implications

a. (U) Conventional Defenses. Adjustments to US land-based forces would be dependent not only on Soviet actions but also on the share of the burden US allies would be willing to assume. US sea-based forces are more directly tied to the changing requirements of the Soviet threat. If the goal were at least as stable a world as provided by currently programmed forces (which include strategic ballistic missiles), substantial conventional force adjustments would be required beyond currently planned modernization programs to both land- and sea-based forces as a hedge against Soviet actions. Likewise, US allies would have to accept their proportional share of the increased conventional requirements. Based on precedent, the prospects of the allies doing so are not good. Not all conventional adjustments would necessarily have to be completed immediately, however, since some could be paced in expectation of Soviet actions.

b. (U) Theater Nuclear Forces. Eliminating strategic ballistic missiles would not change the longstanding requirements for force modernization and improvements to counter the unfavorable theater nuclear, chemical, and conventional arms imbalance favoring the Warsaw Pact. Combining such an elimination with the impacts of the INF agreement would demand strong positive action by the United States to assure European allies that the US-NATO linkage would continue to be staunchly supported. It would also require continued, and perhaps increased, allied support of the remaining nonstrategic nuclear forces. The United States and NATO would also have to continue to remain firm in opposing any reductions or constraints in the remaining INF forces and shorter-range nuclear forces. At stake would be the credibility of the deterrence proffered by the resulting US-NATO Triad of conventional, theater nuclear, and strategic nuclear forces.

c. (S) Strategic Offensive Forces. Ballistic missiles comprise nearly two-thirds of US strategic nuclear forces. To hold the adjusted Soviet target base at risk, most if not all of these weapons would have to be replaced in some fashion and the remaining weapon systems modernized. Disregarding the foregoing additional military requirements, just the additional cost of, for example, the strategic bombers and SLCM submarines required to keep risk essentially equal to today’s level of risk would exceed any realistic projection of near-term defense budgets. The Soviets, with only a limited bomber capability today, would have to grapple with similar considerations in determining the acceptability of proposals eliminating strategic ballistic missiles.

d. (U) Air Defenses. The Soviets have an extensive air defense system. In view of the US vulnerability to ballistic missiles and the past lack of a major air-breathing threat, the United States has chosen to maintain little CONUS air defense capability. If the United States and the Soviet Union agreed to eliminate strategic ballistic missiles, the United States could not afford to remain relatively defenseless against nuclear attack by bombers and cruise missiles. To do so would reduce stability and deterrence thus increasing risk. A CONUS air defense system would require a combination of land- and sea-based early warning and interceptor aircraft, as well as forward-deployed ASW and anti-air warfare forces designed to destroy enemy missile carrying platforms before they close within weapons range. Additionally, a capability to destroy launched ALCMs and SLCMs before they entered CONUS airspace would be critical. Point defenses would also be necessary to protect critical assets from weapons that successfully penetrated into the “terminal region.” If the United States acquired greatly enhanced air defenses, US damage-limiting capability would be significant compared to what it would be without strategic ballistic missile elimination.

e. (S) Strategic Defense Initiative Programs. At least initially, eliminating strategic ballistic missiles would leave the Soviets without the means to achieve their current strategic war aims. Therefore, the Soviets could be expected to retain as many ICBMs as possible throughout the drawdown period, governed by the counting rules, the interim limits and sublimits, and consistent with the production pace required to position a strong substitute force, e.g., an intercontinental bomber and SLCM submarine capability. If the Soviets were unable to meet their targeting requirements using nonballistic strategic arms, and the viability and integrity of their war plans were directly affected, the Soviets would have a high motivation to cheat. Given the potential for Soviet cheating, even in a United States-Soviet zero strategic ballistic missile world, US ballistic missile defensive forces would be required to protect against any covertly held Soviet ballistic missiles and also to deter the use of third nation ballistic missiles. Additionally, US ballistic missile defense forces would guard against accidental or unauthorized launch of Soviet covert or third world ballistic missiles. Thus, there would be a requirement for a substantial investment in defensive systems that would contribute to deterrence through independent objective-denial and damage-limitation. Coupled with strategic offensive, defensive, and nonstrategic nuclear force improvements, a ballistic missile defense capability could raise Soviet uncertainty to the point that they would be adequately deterred.

f. (S) New Programs. Maximum use of US technological superiority will continue to give the United States the capability to offset Soviet quantitative superiority. The Soviets will continue to lag behind the United States in this area, and the leverage that technological superiority provides would have to be exploited. Advanced technologies and appropriate classified programs would require full support and provide the enhanced operational capabilities required to keep risk relatively constant. With an agreement to eliminate strategic ballistic missiles, the modernization and replacement of other elements of US strategic and conventional forces would also take on increased importance. C3I improvements would require continued emphasis because the post-ballistic missile Soviet means of nuclear attack—including covert ones—would still constitute a continuous threat to US continuity of government and C3I systems. The shift to increased emphasis on strategic air-breathing systems would significantly enhance the importance of US advanced bomber and air- and sea-launched cruise missile programs.

4. (U) Conclusion

a. (U) Deterrence of aggression is achieved by maximizing both an aggressor’s uncertainty that he can achieve political objectives by force and the certainty he will face unacceptable risk to what he values most. In transitioning to an alternative future without strategic ballistic missiles, simply replacing ballistic missile warheads with bomber or SLCM-delivered warheads would not maintain a deterrent posture equal to that of today. The composition of the forces would be too different to justify such an assumption at this juncture. The credibility of the threat of escalation by the United States and its allies, as well as the willingness of the allies to accept their share of any increased conventional requirement, would determine the need for increased US conventional force levels. Presently planned modernization programs, both strategic and conventional, would remain vital.

b. (U) If strategic ballistic missiles are phased out, the United States must maintain credible deterrent forces throughout the transition period. This can be done both by adjusting the US force structure to counter an altered Soviet threat and through additional arms control agreements. By making the potential threat more predictable, arms limiting agreements could reduce force structure imbalances and lessen the risk caused by eliminating strategic ballistic missiles. However, arms control agreements that could likely be negotiated cannot alone substitute for offensive and defensive deterrent capabilities. To ensure those deterrent capabilities were available during the transitional phase would require relief from current budgetary constraints.

c. (U) Assuming that an arms control agreement provided for eliminating all strategic ballistic missiles and the necessary funding could be found to support such a transition, the agreement should not be implemented without fully considering the following:

(1) (S)(NOFORN) Although the ultimate goal of eliminating strategic ballistic missile systems would be a more stable world, the transition to this environment would have to be made very carefully and with force adjustments that match the changes in the form of deterrence. Eliminating strategic ballistic missiles without complementary nuclear force modifications and conventional force improvements could have the opposite effect.

(2) (U) This transition scheme, if implemented, would set in motion a fundamental change in the nature of deterrence—from deterrence based principally on offensive retaliation to deterrence increasingly dependent on defensive capabilities. A transition to this form of deterrence is potentially destabilizing unless implemented in a phased manner that ensures the Soviets comply with the agreement, that the United States acquires the force structure required to support the agreement, and that unexpected events do not result in unrecoverable mistakes.

(3) (U) The future strategic environment would be characterized by major uncertainties if such a transition were to be implemented. Real world constraints might result in a transition characterized by tightly constrained offensive capabilities and unconstrained defensive opportunities. As defenses matured and improved, each side would increasingly have less confidence in the ability of strategic weapons to penetrate to target. This uncertainty, coupled with a Soviet desire for a prompt attack capability would create substantial motivation for the Soviets to cheat by retaining a covert strategic ballistic missile force. Therefore, any negotiated agreement to eliminate strategic ballistic missiles must unquestionably ensure a US ability to verify Soviet compliance. Without adequate and vigorous methods of compliance verification, the elimination of strategic ballistic missiles should not be contemplated.

(4) (U) The transition to the elimination of strategic ballistic missiles would be highly contingent on estimates of what the Soviets would do if they agree to eliminate such systems. Thus, should an agreement be adopted, a critical requirement during its implementation is that transition plans be flexible enough to compensate for unforeseen Soviet actions or technological breakthroughs.

(5) (U) Eliminating strategic ballistic missiles would have to be negotiated with the Soviets in a manner that ensured a phased drawdown of the missile systems and left no ambiguity as to which strategic systems would be dismantled in which years. Soviet good will would have to be tested early. If the Soviets are found to be in noncompliance, the negotiated ballistic missile drawdown rate should allow the United States to take appropriate action without suffering a disadvantage.

(6) (S)(NOFORN) The United States will continue to rely on its alliances with or without the elimination of strategic ballistic missiles. Implementation of a treaty resulting in the elimination of strategic ballistic missiles should not be allowed to diminish NATO’s capability to respond to Soviet aggression. To ensure that NATO’s capability is not lessened, NATO allies would have to accept their share of the increased conventional and nuclear requirements that result from eliminating strategic ballistic missiles.

(7) (U) Full support would be crucial for advanced technologies in the required force increases ultimately deemed necessary. These enhanced operational capabilities would provide an essential element of the ability of the United States to keep risk relatively constant.

(8) (U) The imprecise nature of deterrence makes it impossible to determine exactly what forces would be needed to implement such a proposal. Specifically, the philosophy used to select and recommend a future force structure would be requirements-driven, addressing minimum cost alternative solutions that keep as closely as possible within budgetary boundaries. Ultimately, if such a course of action were implemented, risk in the changing environment would have to be continually assessed and necessary force structure adjustments made.

1. Source: Reagan Library, Robert Linhard Files, Arms Control Chronological File, JCS Zero Ballistic Report, 01/06/88. Secret; Noforn. Crowe sent an identical letter to Aspin. (Ibid.)
2. Attached but not printed is the unclassified report.
3. Secret; Noforn.