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

207. Paper Prepared in the Department of Defense for the Verification Panel Working Group¹

Washington, undated.

Limitations on Modern ABM Radar Complexes

I. Introduction

The U.S. July 27, 1971 proposal to limit ABM systems² contains controls on ABM and ABM potential radars. The purposes of such radar controls are to:

1. [1 paragraph (2½ lines) not declassified];

2. Restrict deployment of radars with ABM potential elsewhere in the Soviet Union to prevent deployment of a radar infrastructure that could be used for a nationwide ABM defense;

3. Restrict the expansion base potential of the Soviet ABM deployment;

4. Provide increased confidence in the long term viability of an agreement by including well-defined specific limits on all ABM components.

The U.S. has proposed three ways to control Soviet radars to limit ABM defense capability, while still satisfying U.S. ABM requirements:

• —Limit Soviet ballistic missile early warning radars to those which are now operational and under construction. (In effect, a Hen House freeze.)
• —Limit the deployment of new ABM radars to a limited number of modern ABM radar complexes within agreed geographical areas.
• —Require mutual agreement for the deployment of non-ABM phased-array radars having a power aperture product greater than one-million watts-meters squared, except for those already operational or under construction.

This paper will discuss only the limits on new ABM radars known as “modern ABM radar complexes” (MARCs) within the permitted deployment areas (i.e., 100 km of Moscow). It should be recognized, however, that limitations on MARCs are not independent of the other provisions of the U.S. proposal.

[Omitted here is the discussion section of the paper.]

VII. Agency Positions

The State Department representative believes the listed alternatives are poor and has therefore developed another approach. State believes that in the U.S. interest of reaching agreement we should be prepared to permit construction of those modern radars required to support a Moscow system of 100 launchers. We anticipate that the Soviets would insist on at least two additional faces in the Dog House class to provide coverage of other threat corridors. Clearly they plan to complete the engagement radars now being built at two (possibly three) formerly abandoned ABM sites, and they probably plan eventually to replace dish-type engagement radars at existing sites with Modern radars. State would allow the Soviets to construct additional ABM detection and tracking radars of the Dog House class only to close existing gaps in coverage and would endeavor to have them located at the two existing complexes. However, if they were at a third complex, this would not appear to be a serious problem: there would be little overlap in coverage, so it would be necessary to destroy only one of the three complexes to significantly reduce Soviet capability to defend against attack in the corresponding sector. State would also permit the Soviets to have modern ABM engagement radars at the two new complexes under construction and would allow modernization or replacement of the older dish-type engagement radars at the four existing complexes if necessary. They would disallow any additional engagement radars as being excessive for a 100 launcher level. A power-aperture limitation should be agreed upon consistent with the role of these radars.

The OSD Representative believes that the U.S. position on MARCs as expressed in our July 27, 1971 Draft text is a necessary limit which should continue to be an essential element of the ingoing U.S. position at SALT VI. He believes that the U.S. should continue to press for the MARC concept at Vienna, and that it is in the overall U.S. interests to negotiate as low a MARC limit as possible. Possible changes and alternatives to MARC control are not independent of other possible developments. Whether MARC controls can be relaxed or changed depends on the nature and degree of agreement we can achieve with the Soviets on the specifics of other key problems (e.g., what consitutes testing in an ABM mode; OLPAR limits; EW radar limits). If required as a negotiating lever, OSD believes the U.S. should consider increasing the permitted number of MARCs up to about six. This move would permit further Soviet flexibility with their ABM system deployment, retain the principle of radar control, while still recognizing the fact that the radar infrastructure is the fundamental element in controlling the expansion, clandestine or legal, of ABM systems.

The ACDA Representative believes that there is merit in the MARC concept and that it is in the U.S. interest to keep the number of MARCs permitted as low as possible. At Vienna, we should continue to try to persuade the Soviets to accept the U.S. position on this question. At the same time, if our proposed provisions on MARCs prove non-negotiable, we should be prepared to consider possible compromises which would maintain the vulnerability of the Moscow system and prevent the creation of a radar base for a thick regional ABM defense.

The JCS and CIA Representatives reserve their positions on this subject at this time.

1. Source: Washington National Records Center, RG 330, OSD Files:FRC 330–78–125, Modern ABM Radar Complexes. Top Secret; Sensitive. Forwarded to members of the Verification Panel by Wood under an October 28 covering memorandum. The memorandum explained that the paper, prepared by the OSD staff, was based upon substantive agency comments that had been received by October 23.
2. See Document 183.