127. National Security Decision Memorandum 3161


  • The Secretary of State
  • The Secretary of Defense
  • The Director, Arms Control and Disarmament Agency
  • The Chairman, U.S. SALT Delegation


  • Instructions for the SALT Talks in Geneva

The President has approved the following instructions for the Strategic Arms Limitations Talks. These instructions supplement those contained in NSDMs 285, 301, and 303.2

1. The Delegation should continue to take the position that the U.S. is willing to agree to a resolution of the silo dimension and heavy ICBM definition issues along the following lines:

—The original volume of ICBM silo launchers cannot be increased by more than 32 percent. In this case, there will no longer be a need to specify separate limitations on increases in either the depth or diameter of silo launchers.

—A heavy ICBM will be defined as any ICBM having either a throw weight or a launching weight greater than that of the largest non-heavy ICBM deployed on either side on the date of signature of the agreement.

—The U.S. considers that these two issues have been agreed in principle.

2. The Delegation should modify the U.S. proposal for a ceiling on heavy ICBMs contained in Article IV, Paragraph 7,3 by replacing [Page 583] “volume or throw weight” with “launching weight or throw weight” and inform the Soviets that the U.S. considers it essential that agreement be reached on such a ceiling.

3. The Delegation should propose a definition for the term “throw weight” along the following lines:

The throw weight of a ballistic missile is the sum of the weight of: (1) its reentry vehicles, (2) its penetration aids, and (3) any buses or other devices it has for propulsion, guidance, control, or release which can cause multiple reentry vehicles or penetration aids to reenter the atmosphere at different locations or times.

4. The U.S. Delegation should seek an explicit agreement on the numerical upper limits on the throw weight and launching weight of non-heavy and heavy ICBMs. However, prior to making precise proposals the Delegation should submit for Washington approval a recommended approach on this issue.

5. The U.S. Delegation should bear in mind that the negotiating history has been that the U.S. has cited the SS–19 as the non-heavy ICBM currently possessing the largest throw weight.

Brent Scowcroft
  1. Source: Ford Library, NSC Institutional Files, Box 63, NSDM 316, Instructions for SALT Negotiations. Top Secret; Sensitive. Copies were sent to the Chairman of the Joint Chiefs of Staff and the Director of Central Intelligence. Scowcroft sent this NSDM to Ford under a January 30 covering memorandum for the President’s approval. Scowcroft noted that the NSDM approved the compromise on silo dimension increase achieved by Kissinger in Moscow and contained “an agreed interagency throw weight definition and instructions to seek a heavy ICBM ceiling based on the same parameters, throw weight and launching weight, contained in the heavy ICBM definition.” (Ibid.) Ford initialed his approval of this NSDM.
  2. Documents 93, 99, and 104.
  3. Presumably a reference to the Joint Draft Text. According to telegram 6 from USDEL SALT TWO Geneva, January 30, the most recent Joint Draft Text was agreed upon by the U.S. and Soviet Delegations in Geneva at the end of the negotiating session on December 18, 1975. (National Archives, RG 59, Central Foreign Policy File, [no film number]) The full text of the JDT has not been found, but specific clauses as modified and debated in Geneva in the months following are in telegrams from the delegation, ibid.