169. Memorandum From Acting Secretary of State Katzenbach to the President’s Special Assistant (Rostow)1

SUBJECT

  • ABM Program

You have inquired as to what I think the Soviet reaction would be to an ABM deployment by the United States under either Posture “A” or Posture “B” of Secretary McNamara’s memorandum.2

[Page 408]
1.

It is not presently clear how extensive the present Soviet ABM deployment is. Whether or not they intend presently a full scale deployment, I would assume that the initial reaction of any announcement of a U.S. ABM system would be to encourage and expedite a full scale Soviet deployment.

I base this conclusion on the history of Soviet emphasis on defensive systems coupled with the fact that they have already commenced such a deployment.

I think the Soviet Union will also be forced to react by increasing its offensive nuclear force to take into account our ABM deployment. While it would clearly be rational to do this immediately—and there is no question about Soviet technical competence in this regard—I am less certain as to how quickly they would react. Ideology and history to the contrary notwithstanding, I think we should assume that they will react in this way, although it may not be their first reaction.

The cost of a Soviet ABM deployment and improved and expanded ICBM capabilities might be prohibitive in cost if pursued simultaneously. In this event, the rational thing to do would be to cut back ABM deployment and concentrate on an offensive nuclear force. But the fact that they are defense-minded and that they have already commenced an ABM program might lead them to postpone committing extensive resources to improve ICBMs.

I would agree with Secretary McNamara’s conclusions that a rational response by the Soviet Union would not essentially change the existing situation; but I believe there is a good possibility that this response (offensive missiles) might be delayed for a period of time. If this is correct, deployment of an ABM system would give us a short term advantage over the Soviet Union, and it might be two, three or four years before the status quo was restored. That it would be restored, I have no substantial doubt.

2.

I think the Soviet Government should be approached directly with as candid a statement of the existing situation as security permits—and I think this could be quite candid. I think we should inform them of our intentions, absent an agreement, which would as nearly as possible freeze existing offensive and defensive systems. I think we should state our intention of deploying some ABM system if it is impossible to reach a satisfactory understanding.

The Soviets have always linked the need for a freeze on both offensive and defensive systems. I find this both significant and puzzling since it would seem to me that a purely defensive freeze would be clearly to their advantage. The only explanation of this that I can see is that they do tend to think in defensive terms which, to a degree, would support the thesis that they don’t approach the problem as rationally as we do.

3.
While you have not asked my views on Third Country problems it seems to me that how these are handled is perhaps an equally important problem to be faced.
Nicholas deB. Katzenbach
  1. Source: Washington National Records Center, RG 330, OSD Files: FRC 70 A 4662, 471.94, ABM, November-December, 1966. Top Secret; Eyes Only. A stamped notation on the source text reads “Mr. Vance has seen.”
  2. Reference apparently is to McNamara’s December 2 draft memorandum to the President on the Nike-X, which he circulated at a meeting held on Wednesday, December 7. Thompson’s account of this meeting is scheduled for publication in volume X. At this meeting, McNamara also asked the participants to comment on probable Soviet reactions to both a light and heavy ABM deployment by the United States, Postures “A” and “B.” For responses by Thompson and Helms, see Documents 170 and 171 respectively. Additional responses are scheduled for publication in volume X.