Declassified per Executive Order 13526, Section 3.3
NND Project Number: NND 63316. By: NWD Date: 2011
SECRET/NOFORN
military junta or by Vice President Tho, with the army playing a major if not the predominant role behind the scenes. On the one hand, the military might conclude that a military-led government would be better able to maintain national unity and internal political cohesion and, more importantly, to conduct a determined and effective campaign against the Communists. On the other hand, they might conclude that Tho, who has been on good terms with some of the present military leaders, would not disagree with their views on the manner of conducting the fight against the Communists and that his constitutional succession would legalize the change in government and avert a serious power struggle. Another important factor, which would almost certainly enter into the calculations of the military would be the fortunes of the coup group in South Korea and the course of US-ROK relations. In any event, a government led by the military, by Tho, or by any other civilian approved by the military would probably maintain Vietnam's pro-US orientation.
If a military coup or Diem I s death seriously disrupted government leadership, any momentum the government's counterinsurgency efforts had achieved probably would be halted, and possibly reversed, at least for a time. Moreover, the confusion and suspicion attending the disruption would provide the Communists an opportunity to strengthen their position in the countryside, and they might even be emboldened to attempt to seize control of the government. Since a serious split within the military leadership does not appear likely, Communist attempts to take over the government in Saigon would probably fail.
In the meantime, the Diem government will almost certainly continue to press for increased, aid, further expansion of the armed forces, and a clear priority of military over political and economic efforts to undercut the Communist insurgency. Diem. will be adamant in his views as to how the anti-Communist campaign should be waged and will tend to regard US differences with such views or criticism of his inner circle as indications of weakening US confidence in him. In the event of another coup effort against him, he would probably expect quick and strong US public support. Diem will also continue to press the US for a strong anti-communist posture in the Far East. If he concludes that this posture is wakening, he will almost certainly make strong protests and become increasingly assertive and stubborn in his relations with the US. However, in the absence of any acceptable alternative to US support and assistance to South Vietnam, he is likely to avoid jeopardizing seriously basic US-South Vietnamese ties. Indeed, he would probably seek to establish closer ties with the US by such means as a mutual defense treaty and possibly the stationing of US forces in South Vietnam if, for example, the Communists take over Laos or Communist China achieves a nuclear capability. Failure of current international efforts to establish a neutral Laos or a resumption of all-out rebel military operations in Laos would greatly tempt Diem to increase substantially his covert forces in southern Laos in order to prevent complete Communist control of that area; Diem would probably seek US-Thai participation as well as assurances that the US defend South Vietnam in case such action precipitated open aggression by North Vietnam. Diem would also be tempted to involve his government in another plot to overthrow Norodon Sihanouk in the event the latter became too accommodating to impending Communist pressure in the area.
