#180s

SYSTEM II

90124

THE WHITE HOUSE

WASHINGTON

[[handwritten]] Feb. 16, 1986

[[handwritten]]

Dear Mr. General Secretary

Your letter of Dec. 24, 1985 was most thought-provoking and I would like to share my reactions with you. I have of course also received your letter of Jan. 14, 1986, and will be responding to it shortly. However, since the substance of the latter is already in the public domain, I believe it is well to keep our private communications separate. Although the issues overlap, I would hope that our informal exchange can be used to clarify our attitudes on some of the fundamental questions.

I agree with you that we need to set a specific agenda for action to bring about a steady and - I would hope - radical improvement in U.S.-Soviet relations. I suggested two such topics in my preview letter, and I would hope that we can identify others as ripe for immediate progress. For example, some of the obstacles to an agreement on intermediate-range missiles seem to be falling away. I would also hope that rapid progress can be made toward agreement on a verification regime that will permit a global ban on chemical weapons.

Regarding arms reduction in general, I agree with you that we must make decisions not on the basis of assurances or intentions but with regard to the capabilities on both sides. Nevertheless, I do not understand the reasoning behind your conclusion that only a country preparing a disarming first strike would be interested in defenses against

[[typed]] DECLASSIFIED

Authority: N. Menan, NSC 10/11/91

By: DSD, NARA Date: 10/16/91

ballistic missiles. If such defenses prove feasible in the future, they could facilitate further reductions of nuclear weapons by creating a feeling of confidence that national security could be preserved without them.

Of course, as I have said before, I recognize that adding defensive systems to an arsenal replete with weapons with a disarming first-strike capability could under some conditions be destabilizing. That is why we are proposing that both sides concentrate first on reducing those weapons which can be used to deliver a disarming first strike. Certainly, if neither of our countries has forces suitable for a first strike, neither need fear that defenses against ballistic missiles would make a first strike strategy possible.

I also do not understand your statement that what you call "space strike weapons are "all purpose" weapons. As I understand it, the sort of directed-energy and kinetic devices both our countries are investigating in the context of ballistic missile defense are potentially most effective against point targets moving at high velocity in space. They would be ill-suited for mass destruction on earth, and if one were planning to strike earth targets from space, it does not seem rational to resort to such expansive and exotic techniques. Their destructiveness can never approach that of the nuclear weapons in our hands today. Nuclear weapons are the real problem.