Foreign Relations of the United States, 1981–1988, Volume XI, START I

76. Information Memorandum From the Assistant Secretary of State for Political and Military Affairs (Howe) and the Assistant Secretary of State for European Affairs (Burt) to Secretary of State Shultz¹

Washington, August 10, 1983

SUBJECT

• Basic Elements of the U.S. and Soviet START Positions

This memorandum summarizes and compares the U.S. and Soviet START positions as they stand at the end of Round IV of the negotiations. It is designed as a companion piece to a separate paper² which suggests how the two positions might be combined.

In brief, the U.S. position focuses on achieving large reductions in ballistic missile warheads—to equal levels—and, by a network of constraints, on reducing the large Soviet missile throw-weight advantage. With separate limits on bombers, the U.S. seeks to protect our bomber capability and capture the Soviet Backfire bomber in the agreement. The Soviet position places priority on delivery vehicle (as in SALT II) and weapons limits, although they have yet to propose a specific ceiling on weapons. By providing an overall limit on delivery vehicles, insisting that there is no real difference between missiles and bombers (or their weapons) and refusing to discuss limits that would reduce throw-weight, they seek to protect their advantage in ICBMs.

The following sections discuss the positions in terms of warheads, delivery vehicles and throw-weight. Attached are charts describing the current balance and comparing the two positions to SALT II.³

WARHEADS

The USSR has proposed to aggregate all ballistic missile re-entry vehicles (RVs), ALCMs, and bomber weapons—gravity bombs, SRAMs—into a (so-far unspecified) single limit on nuclear weapons. The purpose of this aggregate limit is to force the U.S. to give up ballistic missile RVs in return for our bomber weapons and any ALCMs we wish to deploy.

The central feature of the U.S. START position has been a separate limit of 5000 ballistic missile warheads along with a sublimit of 2500 on ICBM RVs, aimed at the strategic systems with the greatest first-strike potential. We also have offered to limit ALCMs at a level lower than in SALT II, but we have rejected the Soviets’ attempt to combine armaments for slow-flying systems with those of ballistic missiles.

In sum, the main weapon limits in each proposal are:

USSR	U.S.
• Limit of X on sum of:	• Limit of 5000 on missile RVs
—Missile RVs	—Sublimit of 2500 ICBM RVs
—ALCMs
—Other Bomber Weapons	• Limit of 20 ALCMs per bomber

The key difference between the proposals is the issue of aggregation. The Soviets insist that a weapon is a weapon; the U.S. points out that bombers, unlike missiles, must face unconstrained Soviet air defenses and therefore we cannot equate a gravity bomb to a missile RV. There are, also, important verification issues with bomber weapons. Other important issues related to limits on weapons include:

—The Soviets have told us that the 2500 sublimit on ICBM RVs is unacceptable since it would force them to massively restructure their forces. For our part, we could probably drop the sublimit without consequence since under the 5000 total RV ceiling the Soviets would reduce their ICBMs to somewhere in the 3000 RV range. However, if in the course of the negotiations the 5000 RV limit is raised, we may wish to have such a sublimit. Moreover, it may prove to be of value as negotiating coin.

—We will eventually need to refine the ALCM limit we have proposed. With no other restrictions on our bombers, we could theoretically deploy some 7000 ALCMs (350 bombers x 20 ALCMs per bomber). Yet our production plans only call for a buy of about 3000. And our plans through the early 1990s do not call for ALCMs to be deployed on more than about 200 bombers. (We are therefore considering limits that are closer to our actual requirements, such as 200 bombers × 20 ALCMs per bomber.)

—While the Soviets have not tabled their specific weapon limit, we would expect it to be in the range of 11,000 or so deployed weapons on all strategic systems.

The U.S. and Soviet positions also differ significantly with respect to SLCM. The Soviets have told us that their willingness to limit rather than ban ALCMs is conditional upon our agreeing to ban SLCMs (and GLCMs) of greater than 600 km range. The U.S. has offered no SLCM position in Geneva (we respond to SLCM questions by asking the Soviets how they would verify their proposed ban). Development of a U.S. position on SLCM limits is a high priority task in the START community.

DELIVERY VEHICLES

The central feature of the Soviet position is a set of interlocking limits on bombers and ballistic missile launchers. The structure is that of SALT II, although the numbers are somewhat smaller, in line with the Soviets’ proposal to decrease the overall limit on missiles and bombers to 1800 from the SALT II level of 2250.

The chief problem with such a framework is that it aggregates ballistic missiles, potentially the most destabilizing systems, with slow-flying systems which we consider unsuitable for a first strike and therefore far less threatening. We also have argued that the 1800 overall limit is not low enough, although in the round just past we have indicated our willingness to raise that number. This brings our position closer to the Soviets’ and accommodates the Scowcroft Commission’s recommendation that MIRVed ICBMs give way to larger numbers of smaller, single-RV missiles.

The basic provisions related to delivery vehicles are:

USSR	U.S.
• Sublimit of 680 on MIRVed ICBM launchers
• Sublimit of 1080 on MIRVed SLBM launchers + MIRVed ICBM launchers	• Limit of 850–1250 deployed missiles
• Sublimit of 1200 on ALCM bombers + above	• Limit of 400 (actually 350) bombers
• Limit of 1800 on total missiles and bombers

While we have not offered an alternative to our original 850 limit on ballistic missiles, it is generally understood that we will accept anything up to approximately 1250. This plus 400 bombers (350 is nearer our bottom line) would give a total of 1650 delivery vehicles, close to the Soviet number of 1800. Closing the gap would require more than just splitting the difference, however, since the question of aggregation separates the two positions.

THROW-WEIGHT

The U.S. seeks to reduce the great disparity in throw-weight arising from the large Soviet force of medium and heavy land-based ICBMs. We have tabled a series of specific restrictions on both heavy and medium ICBMs which are designed to reduce Soviet throw-weight to the 2.5 million kilogram range (down from their current 5.6 Mkg and above the 1.9 of the U.S.). In the recently tabled U.S. draft treaty, however, we left the provisions blank, telling the Soviets that we were flexible on the means of achieving the desired reductions.

The Soviets, on the other hand, wish to retain maximum flexibility to structure their forces. They have rejected throw-weight as a strategic indicator of any major significance.

The basic provisions related to throw-weight are:

USSR	U.S.
• Future ICBMs limited to one “light” type only	• Ban on future heavy ICBMs
• No increase in silo volume or conversion of light ICBM launchers to heavy	• Sublimit of 110 heavy ICBMs4
	• Sublimit of 210 on medium ICBMs + heavy ICBMs5
	• RV weight limit on new missiles
	• Limit of 5000 ballistic missile warheads

With regard to throw-weight, the U.S. and Soviet positions have no commonality other than that the Soviet modernization limits would have the same effect as our proposed ban on new heavy ICBMs. They have rejected our “collateral constraints” on heavy and medium ICBMs as well as our suggestion that these limits could be replaced with direct limits on throw-weight. They have also rejected all limits which would explicitly reduce the number of SS–18s below current levels. Since the Intelligence Community believes the Soviets will, in the future, emphasize SS–19 class missiles (comparable to the M–X) rather than heavy ICBMs and the Soviets themselves have indicated that the SS–18s will eventually reach the end of their useful life, the Soviet insistance on no SS–18 limits (beyond those in SALT II) may be an attempt to preserve negotiating capital.

As you know, however, the START IG’s throw-weight study has shown that the most important limit on the Soviet throw-weight is the 5000 ceiling on ballistic missile RVs. This, combined with the Intelligence Community’s initial view that the Soviets are themselves moving toward lower throw-weight systems may mean that our differences can be eventually resolved.

1. Source: Department of State, Executive Secretariat, S/S Special Handling Restrictions Memos 1979–1983, Lot 96D262, Box 24, 1983 (CHRON BY WEEK, YR). Secret; Sensitive. Drafted by Hall and Gordon; cleared by Dean and Dobbins.
2. Not further identified.
3. Attached but not printed are two charts: “Comparison of START Proposals” and “The 1983 Strategic Balance, July 1983.”
4. To demonstrate flexibility, these sublimits were not included in U.S. draft treaty. [Footnote is in the original.]
5. To demonstrate flexibility, these sublimits were not included in U.S. draft treaty. [Footnote is in the original.]