Foreign Relations of the United States, 1964–1968, Volume XXVIII, Laos

392. Letter From the Assistant Secretary of Defense for International Security Affairs (Warnke) to the Assistant Secretary of State for East Asian and Pacific Affairs (Bundy)¹

I–35979/68

Washington, November 11, 1968.

Dear Bill:

As you recall, Walt Rostow asked for an appraisal of possible future troubles in Laos if the North Vietnamese should use there some of the assets currently being used in Vietnam.² I understand that Mac Godley will coordinate the response, which will involve several elements: CIA has prepared a recent SNIE³ on Communist intentions and capabilities in Laos; the Country Director for Laos is working on the political aspects of the problem; and we have been assessing the military options against several contingencies.

The Joint Chiefs of Staff were requested specifically to appraise the military courses of action by which the U.S. Government might respond to three alternative courses of action by the North Vietnamese in Laos:

(1) That the forces withdrawn from South Vietnam will remain in Laos but not engage in any overt action against the RLG forces but will remain as threat to the security of Laos and re-entry threat to South Vietnam.

(2) That the North Vietnamese will provide enough additional support to PL forces to create a threat of overrunning Laos gradually measuring our responses as they go.

(3) That the North Vietnamese will provide sufficient additional support to the PL forces to support an attempt to overrun Laos quickly.

The Joint Chiefs of Staff⁴ consider it appropriate to identify and to appraise possible military actions which the United States might take in response to North Vietnamese actions in Laos. However, with respect to the specific questions posed, the Joint Chiefs of Staff consider it important to recognize two relevant points:

a. First, that the North Vietnamese and Pathet Lao (PL) Forces now in Laos have the capability to overrun most of Laos quickly without reinforcement by North Vietnamese Army (NVA) Forces withdrawn from South Vietnam.

b. Second, that the fact that the PL/NVA Forces have not thus far attempted to overrun Laos is the result of a policy decision and is not due to insufficient means.

Therefore, they consider that the threat postulated in NVN course of action 3 already exists. PL/NVA overrun of Laos can occur without withdrawal of enemy forces from South Vietnam and with no lessening of pressure there. Accordingly, analysis of courses of action available must be considered as a function not of additional NVA support provided to the PL and the resultant threat but of observed PL/NVA actions.

Military actions which the United States could employ in response to NVN course of action 1 (NVN Forces withdrawn from South Vietnam remain in Laos but do not engage in any overt action against Royal Laotian Government (RLG) Forces) are set forth in Appendix A hereto.⁵ As long as PL/NVA Forces do not attempt to overrun Laos, US military actions in support of RLG Forces operating against the PL/NVA should continue essentially as at present. This envisages close air support of RLG Forces by US air elements consistent with the priority of other requirements.

If the PL/NVA take the actions implied in NVN course of action 2 (PL/NVA Forces commence overrunning Laos gradually, measuring US responses as they go), the United States will be required to reevaluate its position and its entire strategy in Southeast Asia. Such action on the part of NVN would indicate that its participation in the Paris talks is fraudulent and that NVN expansionist policies have changed only with respect to direction. If the United States decides to meet this new communist challenge, the most important initial actions should necessarily take place in diplomatic channels, through which the United States could inform Hanoi that continued NVN aggression would result in intensified military action against NVN. It would not be militarily sound to commit US ground forces in Laos unless the decision were also made to destroy the capability or the will of NVN to persist in its aggression. Accordingly, military actions on the order of those presented in Appendix B5 hereto would be required if the United States should elect to defend Laos and defeat NVN. If, on the other hand, the United States were unwilling to assume a national commitment to defend Laos and defeat NVN, US military actions in Laos in response to NVN course of action 2 should be limited to increased air interdiction of base areas and lines of communications in Laos and close air support for defending FAR units.

If the actions implied in NVN course of action 3 occurred (PL/NVA attempt to overrun Laos quickly), the situation would differ from that envisaged for NVN course of action 2, principally with respect to the time available for decision making, diplomatic exchange, and military response. Military actions which might be considered in this situation are those in Appendix B not preempted by enemy initiatives. If the North Vietnamese attempt to overrun Laos quickly, it is unlikely that even greatly increased US air support of RLG Forces could prevent it. Further, it would not be possible to introduce US/allied ground elements into Laos in such force as to prevent PL/NVA Forces from overrunning the country, with the possible exception of forces sufficient to defend bridgeheads across the Mekong River to cover Vientiane and some other key population centers. Subsequently, to recover Laos from the communists would require a major campaign against their forces in Laos, a campaign which would be costly and uncertain of success unless accompanied by the defeat of NVN. If such direct action is not taken, the United States must be prepared to accept communist control of Laos and the resultant substantially increased threat to Thailand and the remainder of Southeast Asia.

Even if a national decision to defend Laos and defeat NVN were made, the Joint Chiefs of Staff consider that unilateral US military action in Laos probably would not be effective in the achievement of US objectives in Southeast Asia. Unless the free nations of the area perceive the threat and respond with the full commitment of their resources, the basis for effective US intervention is missing. Accordingly, the Joint Chiefs of Staff attach the greatest importance to multilateral action in the common defense and to the fullest appreciation of all diplomatic measures before a resort to military alternatives, even those undertaken on a multilateral basis.

We agree with the Joint Chiefs of Staff that we should make every effort to secure diplomatic support for the integrity of Laos and should attempt to obtain multilateral support for any actions we might take. For this purpose, in addition to such diplomatic initiatives previously suggested by ISA, two actions with regard to the RTG might be considered: (1) we could furnish the RTAF with as much training as it can usefully absorb to take over a part of air-support actions in Laos, [less than 1 line of source text not declassified] on the same basis as the US now operates; and (2) we could furnish the Thai armed forces with increased amounts of equipment when it becomes excess to our needs in South Vietnam to serve in part as a deterrent against NVA actions against the Mekong Valley towns.⁶ Both actions would serve the additional purpose of helping to dispose the Thai favorably to grant the US access to Thai facilities should this be desired in a post-Vietnam context.

The Joint Chiefs of Staff consider that the applicability of the military actions outlined in the Appendices hereto can only be determined in the light of all the circumstances obtaining at the time of the decision. Nevertheless, it is their intention to continue their appraisal of these contingencies.

We believe that the foregoing assessment by the Joint Chiefs of Staff offers a sound basis for further consideration of this problem. Dick Steadman’s office will continue to be the focal point for DOD participation in the further development of a report for the White House. Appropriate OSD and Joint Staff members are available whenever Mac Godley is ready to proceed.

Sincerely,

Paul C. Warnke

1. Source: Department of State,EA/Vietnam, Laos, Cambodia Files: Lot 75 D 394, TS. Top Secret.
2. See Document 385.
3. Document 389.
4. The JCS made this analysis in JCSM–650–68, “Contingency Planning for Enemy Action in Laos,” memorandum to Secretary of Defense Clifford, October 30. (Washington National Records Center, RG 330, OASD/ISA Files: FRC 72 A 1499, Laos 000.1–(381 Laos), 1968)
5. Attached, but not printed.
6. At this point there was a marginal note in an unknown hand: “Lao are as reluctant for a Thai embrace as the North Vietnamese for a Chinese.”