Foreign Relations of the United States, 1969–1976, Volume XIV, Soviet Union, October 1971–May 1972

266. Backchannel Message From the Head of the Strategic Arms Limitation Talks Delegation (Smith) to the President’s Assistant for National Security Affairs (Kissinger) in Moscow¹

Helsinki, May 24, 1972, 0930Z.

Tohak 113. Deliver immediately even if Dr. Kissinger is in meeting.

Dear Henry:

Sonnenfeldt telcon² suggests that root of possible misunderstanding between us lies in Soviet formula use simply of the word “missiles” rather than the words (which we have tried to negotiate and which we were planning to make in a unilateral statement) “the largest light ICBM now operational on either side.”³

If at Moscow you can get agreement that there will be no significant increase (a) in the size of ICBM silo launchers, or (b) in the volume of ICBMs beyond that of the largest light ICBM currently deployed by either side, and you can get the word “significant” further defined to be no more than 10 to 15 per cent, that would be great improvement.⁴

Warm regards.

Gerry Smith

1. Source: National Archives, Nixon Presidential Materials, NSC Files, Box 1088, Howe Vietnam Chronological File, May 24, 1972. Top Secret; Sensitive; Exclusively Eyes Only.
2. No record of this telcon has been found.
3. In his memoirs Smith writes that at 9 a.m. on May 24 he learned that the negotiations in Moscow on possible constraints on ICBM modernization now included defining “significant” as no more than 10 to 15 percent. (See footnote 7, Document 263.) He said that although he had been advised not to share this information with anyone until he heard from Kissinger, he passed its substance to the other delegates. He noted that it was just as well that he had because General Allison immediately pointed out that under the proposed formula the United States would have to halt its Minuteman III program, in which 550 single-warhead Minuteman I missiles were being replaced with MIRVed Minuteman III missiles which had “significantly” larger volume than the Minuteman I. Smith wrote that he immediately rushed a message to Kissinger headed “Deliver immediately even if Dr. Kissinger is in meeting” warning him of this danger, and pointing out that the delegation’s earlier proposal to define a heavy missile as one having greater volume than “the largest light ICBM now operational on either side” (the Soviet SS–11) would still permit significant increases in U.S. ICBMs while stopping the Soviet ICBM buildup. (Doubletalk, p. 415)
4. Not knowing how quickly his message would be delivered, Smith also telephoned the Moscow White House and talked to Mossbacher, explaining the effect the provision under consideration would have on the U.S. MIRV program. He said Mossbacher must have been impressed by his urgency, because a Kissinger aide called back, saying they couldn’t understand his message and had thought they were trying to get the definitions precisely as Smith had recommended. Over an open line (to which he assumed Soviet intelligence agents were listening), he advised against using the specific number (10 to 15 percent) to define “significant” as it applied to missile volume. No record of these phone conversations has been found. Smith recalled that he then sent another cable to Kissinger, explaining how the formula under consideration would affect Minuteman III and suggesting one with “no significant increase (a) in the size of ICBM silo launchers or (b) in the volume of missiles beyond that of the largest light ICBM currently deployed by either side, and then define ‘significant’ as no more than 10 to 15 per cent …” (Doubletalk, pp. 415–416)