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

188. Memorandum From the Special Assistant to the Deputy Secretary of State (Timbie) to the Special Advisor to the President and Secretary of State on Arms Control Matters (Nitze)¹

Washington, January 2, 1987

SUBJECT

• SDI

Bob Einhorn and I met with Dr. Allan Mense, the new SDI Chief Scientist. The following items are of interest.

— His thinking closely paralleled our own on how best to distinguish OPP devices that have BMD potential from those that do not. For directed energy systems, he would use power (a few megawatts) and optics diameter (about 5 meters). He confirmed that for continuous wave systems power is the figure of merit; for pulsed systems it is energy per pulse.

— [1 paragraph (5 lines) not declassified]

— Fast-burn boosters represent a major headache for SDI, and a ban on new types of missiles would be looked on with great favor. (Perhaps there is something we can do here, picking up on the Soviet proposed ban on new types, e.g. ban on new types first tested after 1990 (to protect M–X, D–S, and SICBM). The definition of new types might include specific impulse to distinguish fast burn from ordinary missiles).

— Survivability of space-based assets is also a major headache. They don’t have a single solution, so they are pursuing a lot of possibilities like stealth, decoys, defense, proliferation, etc. No one of these will work, but the hope is that a combination will make attack on the system expensive.

— Their approach to mid-course dissemination is similar: any single sensor can be decoyed, but with enough sensors decoys become heavy and expensive. So they are pursuing radar, IR, and various active systems.

— The new heavy-lift systems research money in the DOD supplemental came about when Abrahamson told the President he needed this capability and the President said OK. Abrahamson and Weinberger then put it in the supplemental request with no consultation with the Air Force, NASA, Commerce, etc. A scary procedure.

— He has some people working quantitatively on what the precise thresholds should be to distinguish BMD capable devices from devices not so capable. He welcomed further discussions in a few weeks when this work is further along.

1. Source: Department of State, Ambassador Nitze’s Personal Files 1953, 1972–1989, Lot 90D397, January–February 1987. Secret. A stamped notation indicates Nitze saw the memorandum.