283. Memorandum From the Assistant to the Secretary of Defense (West) to Secretary of Defense Schlesinger 1


  • The Vietnam Historical Effort

I. Background

As a follow-up to your conversation with Bob Ellsworth about a Vietnam history, the bureaucracy is moving to interview refugees. DIA and the Air Force have ongoing efforts, and the Army is planning a sizeable program. The OSD historian proposes that he direct the OSD effort, using the Army interviews and splitting the costs with the Army. The Army plans to spend $500,000 a year for three years for the interview program. The end product will be monographs written by Vietnamese, directed by a small group of Vietnamese working at GRC. Contracts to outfits like GRC have already been let by the Army and the Air Force, with the intent of analyzing different pieces of the Vietnam puzzle; e.g., the Air Force seeks a monograph on The Last Days of VNAF, etc.

The ongoing efforts are not without an element of risk, in that many questions of the ‘why did we lose Vietnam?’ type are included in the interviews. An Ellsberg-type armed with the Freedom of Information Act, teaming up with a hungry reporter, could create quite a storm.

On the other hand, there could be considerable benefit to a Vietnam post-mortem. For example, we may learn how our allies looked at us, how we went about determining our allies’ force structures, how we evaluated our allies, and why. We may also learn more about the causes of the SEA collapse,2 a subject concerning which the impressions of our military and civilian leadership should be clear and correct.

Several members of your staff—Abramowitz, Marshall, von Marbod—believe that OSD should not leave all interviewing and research [Page 970]to the Services; rather, a small effort focused on at least three major topics should be undertaken under OSD direction. These three topics are:

How did we look to our allies? From the Vietnamese point of view, what were our relative strengths and weaknesses? Did we give sound advice? Did we employ sufficient leverage? Did we suggest the proper equipment? Did we fight well?
What do we know about the cohesion and capabilities of our allies? Perhaps even more starkly in the case of Cambodia than in Vietnam, how do we account for the seeming disparity between our reports and the reality of organizational disintegration and battlefield defeat? Did our desires distort our perspectives at every level? Or have we created communication patterns within our country teams which filter out undesired opinions? Or do our information systems focus on the wrong issues, or on an overly restricted set of issues?
How and why do we export force structures? To what extent do special interests from Congress, private industry, State and Service bureaucracies override or unduly constrain “rational” force structure planning in SVN and Cambodia. What were the dominant factors affecting the force structure development in each case? How strong are those factors in current cases, such as Korea and Iran?3

Enclosure 1

Possible Causes for the Collapse of South Vietnam

In examining the collapse of South Vietnam, seven hypotheses deserve careful examination, although not necessarily by DoD. These hypotheses are:


We gave SVN the wrong military organization. We made ARVN in our mirror image. Its organization and equipment reflected ours. This assumed like levels of technological competence or sustained American technical assistance. To bribe or placate Thieu, enormous amounts of disparate equipment were shoved into SVN just prior to the cease-fire, while the cautions and suggestions of many advisers about the appropriateness, usability, durability and maintainability of the equipment were blocked out by a few on the NSC. Burdened with a military establishment too rich and too support heavy, ARVN suffered in several [Page 971]ways. Too many of its more talented personnel were tied to technical support functions, and the entire system could not perform effectively below a critical mass threshold which was pegged quite high. For example, it is one thing to have close air continuously on call; it is another thing to receive only occasional single sorties. When reduced aid drives a system toward the latter case, then the troops would be better off with organic artillery. But, of course, this sort of tradeoff in 1974–75 was not feasible; ARVN was tied to the 1972 force structure decisions, despite CINCPAC’s alleged efforts in 1973–74 to reallocate fiscal priorities among the RVNAF components.

So, one area for DoD analysis might be the process we went through in giving SVN its force structure, with special attention given to parallels to the South Korean case, the Persian Gulf nations, etc.4


The tenacity and spirit of the North and of the Lao Dong party were extraordinary. But why? They endured losses horrendous by historical standards. Perhaps more significantly, they accepted a ceasefire which brought a temporary diminution of hostilities. Many analysts argued “the taste of peace” would create internal pressures in the North which would block Giap’s efforts to again crank up “the green machine,” especially since he failed as dramatically in 1972 as in 1968. Still, by 1974 the NVA was grinding in again. If such doggedness were a function of nationalism, then Thailand’s desire for accommodation may be successful. But if this aggression is fueled by ideology and a ‘manifest destiny,’ then the genuine subjugation of Thailand and perhaps Malaysia may emerge as Lao Dong objectives.

All senior U.S. officials should understand the dynamics of the Lao Dong (Leites’ Operational Code might be an appropriate model); DOD should be especially interested in the links which convert political fervor into military effectiveness, for it is only through such linkages that, for instance, Kim Il Sung can be said to pose a real threat to South Korea.5


The fundamental deterrent to a full NVA offensive was U.S. air power, not RVN capabilities. Congress and the Executive Branch jointly withdrew that deterrent, but the Executive Branch did not notify RVN of that fact. President Nixon secretly assured Thieu, in return for signing the Paris Accords, that the U.S. would strike back with full force if NVN massively violated the ceasefire. The Executive Branch acquiesced in—perhaps even abetted—the Congressional effort to nullify that deterrent. Mr. Ford said in 1973 that, if bombing were again necessary, the President would request it; in 1975 Mr. Ford did not request it. Mr. Kissinger, saying we have learned important lessons from Vietnam, on June 18, 1975, [Page 972]issued a very ambiguous statement about those lessons: “There is no question that popular will and social justice are, in the last analysis, the essential underpinning of resistance to subversion and external challenge. But our support and assistance will be available where it has been promised.”6

While Mr. Ford has said he contemplates no historical analysis of Vietnam and Mr. Kissinger says we have already learned the lessons we need to know, the story of U.S. air power as a deterrent will not be neglected by some competent historian.7

Watergate distracted and gravely weakened the Executive Branch, with especially serious results in the Vietnam situation, given the secretive and centralized nature of our decision-making.8
PRC and Soviet aid to NVN was sufficient for continued NVA offensive operations. Recently (June 23, 1975) Kissinger has downplayed the importance of this aid, saying: “Vietnam was not caused by the Russians . . . the Soviet aid level in Vietnam remained relatively constant . . . our aid level dropped.”9 This can be interpreted as at variation with CIA and DIA data, and as a change from HAK’s position in April of 1974, when he implied that the PRC and the Soviets were cooperating: “Since the signing of the ceasefire the U.S. has been in constant liaison with the interested parties, including those outside of the Indochina area . . . we have used every means at our disposal to encourage a reduction in the level of violence and an orderly resolution of the conflict. We believe these measures have had some success.”10
The U.S. Congress sharply reduced aid to SVN . This resulted in battlefield rationing. Much worse still, it led to a high discount rate being applied to future capabilities and was probably the major factor accounting for Thieu’s disastrous decision to withdraw from MRs 1 and 2.11
The social fiber of SVN may have been unraveling since 1973, and this was not reported to Washington. There are two theories about the RVN collapse. One is that the principal cause was the enormous military blunder by one man in ordering a retreat without proper planning [Page 973]or understanding of the situation. Thieu’s decision to withdraw from MR 1 and MR 2 was one of the major military blunders of the 20th Century.12 Once the rout began, it could not be checked. (We did not do so well ourselves in North Korea in 1950.) But had Thieu not given that order, one theory holds: RVNAF could have fought grimly on, losing a gradual battle of territory and attrition while hoping either for increased aid or a lessening of NVN fervor.

The second theory is that the social cohesion and leadership of the South had been steadily crumbling for months and perhaps years.13 Hence, the end was foreordained; whether it occurred by attrition or by rout is a relatively tactical consideration. Our formal reporting does not substantiate this viewpoint, but now there are allegations that neither CIA nor the DAO had the institutional freedom to report as they would have liked. And on the other hand, some allege the South Vietnamese were falsely encouraged to remain dependent, psychologically as well as physically, upon the U.S. (Are we doing the same in Korea?)

This also raises the question: what do we really know about our allies—their social cohesiveness, leadership, and warfighting capabilities? Did we fool ourselves badly? If so, why? Or were pessimistic reports written, only to be watered down or not transmitted? If the latter systematically occurred, what was the institutional hierarchy and action channels which permitted such centralized control?14

  1. Source: Washington National Records Center, OSD Files: FRC 330–78–0058, 300–399, Vietnam, 1975. No classification marking. A handwritten notation at the bottom of the first page reads: “SecDef has seen.” An assessment of the military’s performance during the evacuation, “Noncombatant Emergency and Evacuation (NEMVAC) Survey Report,” September 3, is in National Archives, RG 218, Records of Chairman, George S. Brown, Box 59, 820, Vietnam, NEMVAC Survey Report.
  2. At Enclosure 1 is a rough cut at identifying those causes. [Footnote in the original.]
  3. Handwritten instruction, “do,” appears above each of the numbered paragraphs. Below paragraph 3, West handwrote: “These studies would be undertaken only if we had the right people willing to do them. More generally, however, some of us feel OSD oversight of the overall historical effort is needed, as Enc. 1 points out.” Handwritten instructions, “West do,” appear below this notation.
  4. Handwritten instruction, “do,” appears above paragraph 1.
  5. Handwritten instruction, “do,” appears above paragraph 2.
  6. Kissinger addressed the Japan Society in Washington on June 18. Excerpts of his address were printed in The New York Times, June 19, 1975.
  7. Handwritten instruction, “no,” appears above paragraph 3.
  8. Handwritten instruction, “no,” appears above this paragraph.
  9. Kissinger spoke in Atlanta on June 23; his speech was reported in The New York Times, June 24, 1975.
  10. Handwritten instruction, “do,” appears above this paragraph.
  11. Handwritten instruction, “do,” appears above this paragraph.
  12. There is a checkmark in the margin next to this sentence.
  13. There is a checkmark in the margin next to this sentence.
  14. Handwritten instruction, “definitely do,” appears above paragraph 7.