146. Memorandum From the President’s Assistant for National Security Affairs (Scowcroft) to President Bush1
SUBJECT
- The Tacit Rainbow Missile and the START Treaty
Tacit Rainbow is a conventionally-armed cruise missile. Nevertheless, it became the subject of last minute negotiations between Jim Baker and Shevardnadze to resolve the nuclear ALCM issue in START at the May ministerial. Since then, critics of START have tried to distort the record on Tacit Rainbow to make it seem as though we made a concession to the Soviets. The facts clearly demonstrate otherwise and we are effectively countering the critics’ arguments.
Tacit Rainbow is armed with a forty-pound high explosives warhead. Launched from B–52 bombers, F–16 fighter aircraft, and from ground launchers, its mission is to suppress enemy air defenses. Under certain optimal conditions, its range can be up to about 800 km. The missile is still in development, with a scheduled deployment in the mid-1990s. The Air Force and the Army eventually hope to buy a combined total of more than 30,000 units.
Although Tacit Rainbow clearly has nothing to do with the strategic nuclear weapons that would be limited in START, it became an issue because we and the Soviets had agreed at the June 1988 Summit to count all “existing” cruise missiles, whether nuclear or conventionally-armed, as though they were nuclear. (“Future” conventional cruise missiles are excluded from START limits provided they are “distinguishable” from nuclear ALCMs.) Consequently, if Tacit Rainbow were deemed to be an “existing” cruise missile, it would have to count against our START [Page 803] limit of 6000 nuclear warheads. As a practical matter, this would mean that we would be unable to deploy this very valuable conventional capability.
The final obstacle to reaching agreement with the Soviets on nuclear ALCM limits was the determination of the range threshold, i.e., the range above which the ALCM would count against the START limits. At the May ministerial, Jim told the Soviets we could accept their proposal for a 600 km range threshold provided that Tacit Rainbow was treated not as an “existing” but rather as a “future” conventional cruise missile.
Gorbachev shook hands with Jim on that deal, but that very evening the Soviet military began to walk the agreement back by insisting that a variety of additional limits be imposed on Tacit Rainbow. We rejected any such conditions because START does not limit conventional cruise missiles.
In an effort to give the Soviets a face-saving way to back down from their new demands, the next day Jim gave Shevardnadze a letter2 on the Tacit Rainbow missile. I suspect that Shevardnadze was able to use the letter to good effect in overcoming internal objections to the ALCM deal he and Gorbachev had made. Whatever the explanation, Baker and Shevardnadze met later in the day to confirm that complete agreement on the ALCM issue had been reached.
A copy of Jim’s letter is attached at Tab A. As you will see, the letter simply reiterates previous U.S. proposals and records several well known facts about the missile. Contrary to what some critics are claiming, it does not accept any limits on Tacit Rainbow nor assume any new obligations.
- Source: George H.W. Bush Library, Bush Presidential Records, Brent Scowcroft Collection, USSR Chronological Files, START Files, Soviet Power Collapse in Eastern Europe—Strategic Arms Control (June 1990). Secret. Sent for information. Copied to Quayle and Sununu. A stamped notation at the top of the memorandum reads: “The President has seen.” Bush initialed the memorandum in the upper right-hand corner.↩
- Printed as Document 128.↩