Foreign Relations of the United States, 1969–1976, Volume XXXII, SALT I, 1969–1972

60. Memorandum From the Under Secretary of State (Richardson) to President Nixon¹

Washington, March 25, 1970.

SUBJECT

• Desirability/Feasibility of MIRV Ban

After the NSC meeting this morning you asked me to give you in writing the points I made orally at the meeting on the elements which would influence our position on the desirability and feasibility of a MIRV ban.²

1. Targeting—If substantial counterforce capability in addition to assured destruction capability is an essential element of U.S. strategy, it follows that we have to (a) go ahead with MIRV deployment and (b) improve MIRV accuracy.

2. Numbers—Even if we do not seek substantial counterforce capability, we would still need MIRVs unless the Soviets agree to a limit on the aggregate number of SS–9s and SS–11s. The size of this number would have to depend upon whether and when the SS–11 will be accurate enough to knock out hard targets. The maximum limit we could tolerate is a number of Soviet hard-target warheads equal to the number of our Minuteman sites. If this number is not exceeded, the Soviets are unlikely to target all their land-based warheads against our Minuteman sites; if they do—and crediting them with 100 percent reliability—we would still have left the assured destruction capability of our SLBMs and bombers.

3. ABMs—Notwithstanding numerical limits on ICBM launchers, a MIRV ban is feasible only at low ABM levels. Safeguard and its Soviet counterpart would require so many associated radars as to be easily subject to thickening either by (a) adding ABM launchers or (b) tying SAMs into the radar system. State, CIA and ACDA believe that a limitation on the number of large radars could provide reasonable confidence in the observance of an ABM limit for the next five years at least. JCS doubt this.

4. Verification—Even assuming that we do not seek substantial counterforce capability, that we can agree on a satisfactory limit on the number of ICBM launchers, and that we can also agree on a low ABM limit, we still cannot accept a MIRV ban unless we can also have confidence that it can be verified. Such confidence (aside, of course, from on-site inspection) depends on our ability to monitor a ban on MIRV testing by reliance on national means alone. State, CIA and ACDA believe that we would be justified in such reliance. JCS do not believe so.

ELR

1. Source: Washington National Records Center, RG 330, OSD Files: FRC 330–76–076, Box 12, USSR, 388.3. Top Secret. On March 25 copies were sent to Laird, Packard, and Wheeler. A notation on the memorandum indicates that Laird saw it on March 27.
2. See Document 59.