139. Special National Intelligence Estimate1

SNIE 10–3/1–65


The Problem

To estimate Communist reactions to a US course of sustained air attacks on North Vietnam.

Scope Note

This estimate is intended to supplement, not to supersede, SNIE 10–3–652 on the same subject, dated 11 February 1965. For example, the probable involvement of Communist air forces is discussed in that paper, and not in this.

The Estimate

1. The US air attacks on North Vietnam have added another ingredient to an already intricate and complex situation. Hence Communist reactions to these attacks will not be the product of the attacks alone, but will be governed by numerous factors: the state of relations among the USSR, Communist China, and the DRV; the attitudes and conduct of various free world powers—especially France; developments in the UN; the [Page 321]course of events in South Vietnam; the manner and pace with which the US air attacks develop and the policy of the US itself, not only as this policy may be enunciated by the administration, but also as the Communists may read the influence upon it of newspaper and Congressional declarations and other expressions of diverse views. We cannot estimate with confidence or precision how these factors will interact in weeks to come.

Reactions to the Bombings of Early February or to a Few More of the Same Type, South of the 19th Parallel

2. To establish Communist power in South Vietnam and to unify the country under the Hanoi regime is the primary national objective of the DRV leaders. From the beginning of the insurrection in the South, however, they have consistently admonished their followers to be prepared for a long struggle. Only in the past few months have they occasionally talked in terms of victory being near. This feeling may have been dampened somewhat by the past week’s tougher US action.

3. There are probably some among the DRV leadership who would prefer a cautious course. They would urge that collapse of GVN resistance is inevitable in time despite any amount of foreign support, and that it would be foolish to risk destruction of the DRV’s laboriously acquired modern economic sector merely to accelerate the pace of victory. However, in the present moment of high emotion in Hanoi they probably hesitate to voice such thoughts.

4. To the militant majority, the recent US air attacks probably appear to be the actions of a foe endeavoring to ward off defeat. These leaders probably reason that if the DRV/VC stand firm or even increase their pressures in the South, they will have to ride out a few more such US attacks, but that the US/GVN disposition to continue the struggle will decline. To these leaders, any display of apparent weakness in the face of the bombing would signal to the US that it had hit upon the way to get what it wants in the area.

5. We accordingly believe that the DRV/VC reaction to a few more air attacks like those of early February would probably be to continue their pressures in the South more or less on the scale of recent weeks—always with an eye upon factors like those mentioned in paragraph 1. At the moment, the Communists cannot be sure whether US actions presage a sustained course of air attack or a “tit-for-tat” program of limited reprisals to specific provocations. It is possible that they would, for a week or two, refrain from direct attacks on US installations, but we cannot estimate that such restraint is probable.

6. The Chinese Communists will almost certainly encourage the DRV in the more militant course. We do not believe that they will intervene in Vietnam with substantial military force during this stage. We see [Page 322]no evidence at present of preparations to do so, although we cannot have full confidence in our ability to detect such preparations.

Reactions to a Declared and Sustained US Program of Bombing in the North

7. Over the past decade the DRV has invested much time, effort, and capital in the development of industry, transportation, and relatively modern military facilities. They will not lightly sacrifice these hard-won gains. Yet a threat by the US to mount sustained attacks on these assets would probably be greeted in Hanoi with mixed feelings of trepidation and skepticism. At the start, the Communists would not be convinced that the US intended really to follow through with this program. They would almost certainly apply a range of pressures in an endeavor to make the US desist. They would maintain strenuous diplomatic and propaganda efforts to organize international influence against the US policy. They would probably threaten dire consequences to US interests in the area. Chinese Communist threats would be more insistent, and Chinese Communist forces would probably be deployed in more threatening postures. Viet Cong attacks would probably continue, though not necessarily at a steady pace.

8. If despite these pressures, the US vigorously continued in its attacks and damaged some important economic or military assets, the DRV leaders would have to reach a decision. They almost certainly believe that, while the US could destroy much in their country by air attacks, these alone would not cause their regime to collapse or prevent them from continuing to support the insurgency in the South. And they may believe that their international political position would improve if they became the object of sustained air attack from the US. Accordingly, they might decide to intensify the struggle, accepting the destructive consequences in the North in the expectation of early victory in the South.

9. It seems to us somewhat more likely however that they would decide to make some effort to secure a respite from US air attack, especially if the US had indicated that such a respite would follow a sharp reduction of Viet Cong activity.3 We do not know how far they would go [Page 323]in concessions, whether the US would accept what might be offered, or what the international situation might be at such a time. We think it extremely unlikely, however, that Hanoi would concede so far to US demands that it would entail abandoning its support of the insurgency in the South or giving up its intention of unifying Vietnam under Communist control.

Moreover, the assumed vigorous US attacks on major targets could easily coincide with the probable use over the DRV of Chinese air defense from Chinese bases. If so, US responses would either have been to acknowledge the privileged sanctuary of Chinese bases or to strike the bases in hot pursuit, thus inviting further Chinese military responses. Hanoi’s persistence would be reinforced either way. [Footnote in the source text.]

10. The Chinese Communists would almost certainly be willing to support the DRV in even the more militant course of action outlined in paragraph 8. We have set forth in SNIE 10–3–65 (paragraphs 16–18, with State Department footnotes of dissent) the use the Chinese would be likely to make of their own forces.

Possible, but Unlikely Reactions

11. Instead of temporarily easing off or intensifying present levels of pressure, the Communist leaders might actually engage in actions which would change the scale and nature of the war. These would be much more dangerous and aggressive courses and, although they seem to us unlikely in the light of logic and prudence, they are possibilities which cannot be ignored:


They might launch a large-scale DRV invasion of South Vietnam and/or Laos. We think it unlikely that they would do this in response to bombings of North Vietnam. They would feel that at best this drastic policy would only accelerate victories in Laos and Vietnam which they are confident they will win before very long through less costly tactics. Such an invasion would virtually require a greater involvement of the Chinese in Vietnam, which is in itself distasteful to the North Vietnamese. The Communists would recognize that to launch such an invasion would be to invite further major destruction upon the DRV and perhaps upon China.4

Furthermore, if the DRV should persist in this fashion, Peiping would probably introduce limited numbers of Chinese Communist ground forces into the DRV as “volunteers,” both to prepare for further escalation and to make clear Peiping’s commitment to assist the North Vietnamese. [Footnote in the source text.]

We think it unlikely that the Chinese or DRV would respond to US air raids by air attacks on US aircraft carriers or South Vietnamese air-fields. To do so would invite counterattacks on the vulnerable Communist [Page 324]bases and start the escalation of an air war, a form of hostilities most disadvantageous to the North Vietnamese and the Chinese. A sneak attack on a carrier by an unidentifiable Chinese submarine is a more difficult possibility to weigh, but we are inclined to think the chance is slim; the risks would be fairly high and Chinese confidence in the ability of their inexperienced submarine force to pull it off is probably low.
We also think it unlikely that the Chinese Communists would start another major crisis elsewhere on the periphery of China. Faced with the possibility of a full scale war in Southeast Asia, Peiping would want to have the greatest possible strength focused there. Chinese propaganda has, indeed, said that America’s “meager force” in Asia is spread thinly over a “long arc from South Korea to Indochina,” and that if the conflict were expanded, the “time, place, and scale of the war would be beyond US control.” However, we think this is no more than a general warning of the dangers of expanding the war. Peiping is likely, however, to continue talking of war “over a vast front” and perhaps even to stir up alarms elsewhere to keep US power dispersed and deter the US in Southeast Asia. The Chinese Communists might, for example, increase the apparent military threat in Korea, bombard the offshore islands in order to raise tensions in the Taiwan area, or perhaps make threatening moves on the borders of India.

The Soviet Ingredient5

12. Assuming the fairly limited Soviet involvement which we have estimated, Soviet policy is not likely to have a determining impact on DRV and Chinese policy. The fact that the Soviets have become involved at all, however, almost certainly has some effect on DRV and Chinese calculations. How the Soviet involvement affects DRV reactions will depend upon the extent of whatever Soviet commitment has been given. If the Soviets have urged caution, the DRV might be somewhat more restrained and flexible in its responses to US pressure than we have estimated above. However, we believe it more likely that Soviet promises of aid for DRV defenses, along with the very fact of Soviet reinvolvement will make the DRV leaders somewhat more confident and aggressive. They may hope to benefit in their confrontation with the US from a Sino-Soviet competition in backing them.

13. The probable effect on the Chinese of the increased Soviet presence is certain to be complex and ambivalent. On the one hand, the Chinese are almost certainly upset at an apparent Soviet move to grab a share of credit for any Communist gains in Vietnam and to try to displace some of Peiping’s influence over the DRV. On the other hand, they welcome [Page 325]whatever additional deterrent can be laid upon the US by Soviet involvement in the situation. More important, they see an opportunity to force the USSR either to endorse the Chinese line on policy toward the US or to expose itself as faint-hearted in its devotion to Communist duty. Whichever choice Moscow makes, Peiping expects Soviet authority to be undermined, and Chinese influence strengthened, in the international Communist movement.

  1. Source: Johnson Library, National Security File, National Intelligence Estimates File, 10–5, Communist States. Secret; Controlled Dissem. The Central Intelligence Agency and the intelligence organizations of AEC, NSA, and the Departments of State and Defense participated in the preparation of this estimate. It was submitted by the Director of Central Intelligence and concurred in by all the members of the U.S. Intelligence Board, except for the Assistant to the Director of the FBI, who abstained on the grounds that the subject was outside his jurisdiction.
  2. Document 111.
  3. The Director of Intelligence and Research, Department of State, believes this course of action less likely than that described in paragraph 8. He considers that Hanoi would feel that any benefits to be gained by such a respite would be more than offset by a loss of momentum at a time when victory appeared near, by a loss of face with the VC, and by the consequent bolstering of US/GVN morale. Hanoi would have in mind that concessions under such circumstances might only invite the US to resume strikes upon any renewal of Viet Cong military activity.
  4. The Director of Intelligence and Research, Department of State, believes that paragraph 11a is applicable only in the initial stages of bombings in North Vietnam, well below the Hanoi-Haiphong target complex. Once US attacks destroy major industrial and military targets in this complex, however, Hanoi will have substantially lost its hostage and suffered the maximum damage it could anticipate from the air. In this case the DRV, having suffered the destruction of its major military facilities and the industrial sector of its economy, would probably carry on the fight and proceed to send its own armed forces on a large scale to Laos and South Vietnam. Hanoi might assume that the US would be unwilling to undertake a major ground war, or that if it was, it could ultimately be defeated by the methods which were successful against the French.
  5. Possible Soviet reactions are discussed in SNIE 10–3–65. In the two following paragraphs we consider only the impact of Soviet policies on DRV and Chinese Communist reactions. [Footnote in the source text.]