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The Causes of American Intervention in Vietnam

Ryan Thomas is a university student with an extensive interest in history that heavily influences his gaming preferences.


Vietnam is a sad story in the 20th century, a country which endured three decades of terrible war. Before and during the Second World War it was part of French Indochina, a French colony. After the war, a Vietnamese government led by the Vietnamese leader Ho Chi Minh tried to gain independence for Vietnam : this failed, in the face of French opposition, miscommunication, and chaos. A vicious war broke out, where French, assisted by America, tried to defeat the Viet Minh, the Vietnamese independence movement. From 1946-1948, it consumed Indochina, until a peace agreement after the Vietnamese victory at the encirclement battle of Bien Dien Phu led to a Viet Minh controlled North Vietnam, and a Western - initially French, but soon American - aligned South Vietnam. Supposedly the two would be re-unified soon, in 1956, but this re-unification election never came.

Instead, Vietnam would be bound for another war. The South Vietnamese regime was not stable, both in its political echelons and in the countryside, which resulted in the formation of a powerful guerrilla front opposed to the government in the form of the NLF, the National Liberation Front, known to the Americans as the Viet Cong. This group was initially widely crushed by the South Vietnamese government, but then rapidly grew from 1960 onwards. By 1964/1965, the South Vietnamese government was on the verge of collapse, and the US was faced with the choice to either let its ally collapse, or to intervene. It chose the latter, much to its grief.

It all seems very inevitable in retrospect, but the intervention in Vietnam was a conscious decision, one undertaken despite policy figures in the US government believing it to be un-winnable or too costly. Senator Mike Mansfield said it was too costly relative to the American interests at stake, Vice-President Hubert Humphrey was opposed to increased intervention in Vietnam, as the war would be unable to maintain domestic support, and too costly for its worth. Wayne Morse, Ernest Gruening, and Frank Church, the three being Democratic senators, were all opposed to the escalation of military hostilities in Vietnam. George Ball, the undersecretary of state, was opposed to intervention, drafted a 67 page memo about the costs and benefits that declared it was too costly, and said "Within five years, we'll have three hundred thousand men in the paddies and jungles and never find them again. That was the French experience." Instead, his recommendation was for the US to cut its losses and attempt to reach a negotiated settlement. William Bundy, the future secretary of defense for international affairs under Kennedy, argued that the loss "could be made bearable", and that instead the US should focus on getting out with honor.

Never the less, the majority of US governmental decision makers were firmly in favor of intervention. Why was that so? What were the reasons US policy makers were so confident about the plunge into Vietnam?

Underestimation of the costs required to defeat guerrilla enemies, and overestimation of American experience.

During the initial stages of the Vietnam War Americans had the unfortunate fate of believing themselves better prepared and trained for guerrilla conflicts than was actually the case. This stems from the fact that a disproportionate number of its Cold War leaders had served in special forces in WW2. Roger Hilsman, later to be a key figure in early US policy in Vietnam (in both counterinsurgency warfare and in the strategic hamlet program), had during the Second World War fought in allied guerrilla formations against Japanese forces. This led him into the belief of his understanding of guerrilla operations as waged by the Viet Minh and how to defeat them. This proved to be experience not easily applied - - the US in the Second World War had been supplying and aiding guerrilla movements, in a war less charged with ideology and social movements. It lent a false sense of security about the US ability to defeat guerrilla units twenty years onwards.

Requirement to act, to do something

For decisive men, used to power and success and at least the capability to influence the course of history - something taught to them by decades of careers in politics and their patrician and upper class upbringings - nothing perhaps is more insidious than that of not being able to do anything at all. Americans in Vietnam had an option to either act, or to not act, to take matters into their own hands or to watch powerlessly as the situation developed. Add in politics, and it becomes even more vital for US policy makers to do something. Barry Goldwater during the 1964 election portrayed himself as a strong and courageous figure who would bring the battle to the enemy, and that President LBJ was engaging in “backdown manship” towards the enemy. For Lyndon Baines Johnson, the necessity to do something in response was obvious, and thus retaliatory bombings of North Vietnam provided important domestic advantages.

This necessity to act meant that even when politicians decided their chances in the war were not very good - such as Paul Nitze, navy secretary, who thought the US only had a 60/40 chance to win - they still thought it necessary to intervene.

Discrediting of compromise-oriented elites

During the near-two-decades preceding the US intervention into Vietnam, US elites had been faced with a constant campaign of inquisition against them, launched by conflicting and rival segments of political decision makers. This had directed itself against a host of foes, including alleged communists and homosexuals, but it also focused specifically upon weakness of US political elites : in this regards, the two were linked, as homosexuals were viewed as weak and being weak on communism gave rise to the allegation that one was a Communist. As a result, US political elites, afraid of a repeat of the American equivalent of the Great Purge against them, had to be as strong and as determined as possible against Communism to prevent their rivals from taking advantage of their “softness” against Communism.


Political risks of compromise and perceived weakness

For the United States in the 1960s, compromise was an unacceptable option with communism. The reasons for this partially stem from the section discussed above, relating to the immense political pressure which had been placed upon US political elites. Furthermore, the US was intensely concerned about “credibility.” A loss in Vietnam, a state which the US had guaranteed the existence of, would mean that the US would face charges that it was weak and “not credible”, unwilling to stand up to its commitments.

The fact that these allies were not enthusiastic about the US fighting in Vietnam in the first place, of course, did not enter into US calculations. "Japan thinks we are propping up a lifeless government and are on a sticky wicket. Between [a] long war and cutting our losses, the Japanese would go for the latter", was the opinion of the ambassador to Tokyo : in similar form, most European allies thought the operation irrelevant to their own security.

Failure to listen to wise French council.

Unfortunately, the United States was unable or unwilling to listen to the excellent advice tendered by our experienced French allies who correctly predicted many of the weaknesses of the US in Vietnam and the lack of a US exceptionalism vis-à-vis the French war there a decade earlier. If the US had more carefully listened, it might have understood that the war was unwinnable, as it rested upon the most insubstantial of conditions. Instead, Republicans in the US critiqued President Johnson turning down Charles de Gaulle’s neutralization proposal with insufficient firmness.

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Excessive faith in influence of aerial bombardment.

Americans believed all too often that the war could be won simply and easily, by a campaign of aerial bombardment. The American journalist Joseph Alsop who predicted a collapse of Vietnam without US aid, proposed a US aerial bombardment of North Vietnam that would convince North Vietnam to back down in its conflict with the South. For the United States, bombing would thus be a silver bullet which would enable them to impose their will with minimal casualties - - this would prove to not be the case, and the war would turn into a long bitter slog on the ground where bombing’s impact was minimal.

Senator Richard Russel's words were perhaps the most prophetic concerning air power in Vietnam.

"Oh hell! That ain't worth a hoot. That's just impossible. . . . We tried it in Korea. We even got a lot of old B-29s to increase the bomb load and sent 'em over there and just dropped millions and millions of bombs, day and night, . . . they would knock the road at night and in the morning the damn people would be back travelling over it. We could never interdict all their lines of communication, although we had absolute control of the sea and the air, and we never did stop them. And you ain't gonna stop these people either.


The Domino Theory

The domino theory is a famous theory related to Vietnam, where the loss of Vietnam would result in country after country falling to communism, until inevitably the US position in Eastern Asia was destroyed and its position in the world fatally weakened. Indeed, predictions for this were sometimes apocalyptic in nature. Joseph Alsop, an influential US journalist, predicted that the loss of South Vietnam would mean the loss of all of Southeast Asia, the loss of Japan and the entire Pacific, followed by the possible collapse of Indian democracy to communism and communist offensives across Africa. However, such panicked assertions were not always the rule. At the same time that the domino theory was proclaimed by US policymakers President Johnson seemed curiously unattached to its reasoning. “I don't think it's worth fighting for and I don’t think we can get out. . . . What the hell is Vietnam worth to me? What is Laos worth to me? What is it worth to this country?”

Instead of being viewed as a cogent theory, or at the very least one which was a US policy maker’s rational response to communist expansionism in Asia, the Domino Theory might instead be viewed as a self-reflection of the US’s own view of itself and the battle against communism - - failure of the US to support regimes meant their inevitable fall to communism. While US support could save them, the enemy was a faceless and inhuman horde which could not be negotiated with and which only sought expansion, and only US strength could counter Communist aggression, with “weakness” resulting in the destruction of the United States.

Loss of prestige from another "loss" of China event

Even though Vietnam and Indochina as a whole had little value to the US, as admitted by President Johnson, there were pressing political reasons for ensuring that there could be no more “China.” Any US president “losing” another Asian country to communism would be instantly derided as weak, and the American Congress had made it clear that no President could hope to survive the political damage of yet another defeat. This led to the dreadful situation that for the US, politically, it either had to risk it all on the hope that it could win a war that many of its own policy makers recognized as being unwinnable, or face a crippling domestic political backlash. Instead of being able to choose its fights, the US by domestic political pressure was forced to fight a war it could not win.


In the end, all of these played their role. The US entered a war where it thought it had no choice but to risk it all under the belief that if it didn’t, it would face its position in the world undermined : by its own logic it created a false dichotomy between a catastrophic loss and defeat of its authority in South Vietnam, or a full scale entrance into the war. This came from both logical reasons, but also from ones which were deeply tied to the US self perception and the moral structure of its leadership.

The most penetrating quote to me is one by President Lyndon Baines Johnson. LBJ discusses the need to intervene in Vietnam, ending with “For this time there would be Robert Kennedy . . . telling everyone that I had betrayed John Kennedy’s commitment to South Vietnam . . . That I was a coward. An unmanly man. A man without a spine.” This is of course, involves in part political concerns about the loss of Vietnam, and how it would catastrophically undermine the position of the president. But even more so, it concerned itself with gender and deeply personal relations : it would be that Johnson would be a coward, that he would be unmanly, that really disturbed him. In the fact of such intense fears on the part of US leaders, a US entry into Vietnam moved from being something that was obviously an unwinnable proposition that should be avoided, to one which was an unwinnable proposition where the United States had to risk everything - its credibility, its prestige, its moral standing in the world, the unity of its society, and the lives of tens of thousands of its soldiers - upon the chance that she would be wrong, and that victory could be won after all in Vietnam. The greatest irony of all is that the course undertaken only proved the predictions about loss of credibility and prestige true.



Dean, D. Robert, Imperial Brotherhood: Gender and the Making of Cold War Foreign Policy. Amherst, University of Massachusetts Press, 2001.

Merrill, Dennis and Paterson G. Thomas. Major Problems in American Foreign Policy, Volume II: Since 1914. Wadsworth Publishing, 2009.

© 2017 Ryan Thomas

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