57. Memorandum From the Secretary of Defense (McNamara) to the Chairman of Joint Chiefs of Staff (Taylor)1

SUBJECT

  • Vietnam

As you are aware, one of the alternatives which is now being reviewed with respect to the situation in Vietnam is a carefully planned program designed to exert increasing military pressures upon the government of North Vietnam, with a view to inducing that government to terminate its support and encouragement of the insurrection in South Vietnam and curtail Pathet Lao activities in Laos. The military pressures which might be applied extend from relatively minor covert activities, which you are already examining, to open GVN or U.S. air or sea non-nuclear attacks upon the DRV.

There are a number of military uncertainties which must be resolved, to the extent possible, before political decisions affecting such military actions can be taken. Accordingly, I should like to have your views upon the following matters:

1.
The overall capabilities of the DRV and of the Chinese Communists for military action, with specific reference to:
(a)
The types and magnitudes of actions which are possible, taking into account current Communist logistic capabilities.
(b)
The geographic areas within which such actions might be undertaken.
(c)
The time period within which the enemy forces could be brought to bear.
(d)
The enemy capability for concurrent reactions, as for example, reactions both in Southeast Asia and in Korea and/or Taiwan off-shore islands.
2.

What military actions against North Vietnam, employing air and naval power, but not ground forces beyond the scale of smallscale raids, might be:

(a)
undertaken by the GVN and within the plausible range of GVN capabilities
(b)
assertedly undertaken by the GVN, even if outside the plausible range of GVN capabilities;
(c)
undertaken by the U.S. without public acknowledgment;
(d)
undertaken by the U.S. along with, or after, a public declaration by the U.S. of an intent to exert military pressure upon the DRV with a view to forcing a termination of the insurrection in the South?

What targets would be most effective to attack from the standpoint of:

(a)
specific effect on DRV capability against Laos, South Vietnam, and Thailand;
(b)
interdiction of main communication routes between the DRV and Communist China, plus interdiction of sea communications into North Vietnam;
(c)
more generalized target patterns designed to inflict damage on key installation in the DRV but to minimize the effect on the civilian population as a whole?

While the assessment of the impact of possible courses of action on DRV continued support of operations in South Vietnam and Laos is in large part an intelligence question that should be addressed by intelligence authorities as well, I would appreciate the views of the JCS as to the courses of action under one or more of the above headings that would in your judgment be most likely to bring about cessation of DRV support for operations in South Vietnam and Laos and at the same time be least likely to lead to stepped-up conflict and adverse reactions in third countries.

3.

Assuming that, in response to the attacks upon the DRV, the DRV and/or the Chicoms undertake large scale troop movements over the border into one or more of:

(a)
South Vietnam
(b)
Laos
(c)
Thailand or Burma
(d)
South Korea
(e)
Taiwan

What U.S. effort, air, sea, and land, would be required to contain such an invasion? If intelligence indicated that such a movement were contemplated by the enemy, what actions against North Vietnam and mainland China would be likely to deter such a response?

In each of these circumstances, or any likely combination of them, to what extent could the U.S. effectively counter such actions through air and naval responses only (without the use of ground forces other than those presently deployed) utilizing each of the following means:

(a)
conventional ordnance only:
(b)
conventional ordnance plus classified non-nuclear munitions. The degree of increased effectiveness to be expected from the latter should be specified along with the considerations for and against employment.

[Subparagraphs (c) and (d) (5–1/2 lines of source text) not declassified]

4.
Assuming that the Chicom reaction included air action from mainland bases (either against SVN or other air bases, or supporting aircraft carriers) to what extent could this air threat be countered by: [Page 99]
(a)
actions against enemy aircraft only, without attacks upon mainland bases, or
(b)
selective attacks upon the Chinese bases and air defenses utilizing:
(i)

Conventional ordnance (plus classified munitions if significantly more effective)

[Subparagraph (ii) (1–1/2 lines of source text) not declassified]

[Subparagraph (c) (2 lines of source text) not declassified]

5.
What modifications must be made in existing contingency plans in order to provide for U.S. reactions which would depend primarily upon air activities rather than the intervention of substantial U.S. ground forces?

In view of the broad scope of these questions, I believe that the JCS will wish to create a special planning unit that can devote itself exclusively to these problems on a continuing basis. I appreciate that a detailed response may require a longer time, but believe that we must have your preliminary judgment on these questions for consideration prior to our anticipated departure for South Vietnam about 4 March. Accordingly, I would appreciate it if a preliminary response could be available for discussion with me not later than Monday, March 2. Our review at that time will almost certainly uncover additional questions and refinements that would form the basis for the next phase of the examination.

Robert S. McNamara
  1. Source: Washington National Records Center, RG 330, OASD/ISA Files: FRC 68 A 4023, Vietnam 092. Top Secret. Attached to the source text was a covering memorandum from William Bundy to McNamara, February 21, which reads as follows:

    “The attached memorandum, prepared in response to your request, will obtain JCS views on a number of critical questions affecting our actions in Vietnam. The answers will also be helpful to the work of the Sullivan Committee. We have coordinated this request with the Joint Staff.”