I think that the Vietnam War was justified as the Americans were trying to help Vietnam becoming communist country and they though that communism was a bad thing not realizing that the Vietnamese had it rough to start with. It was just some of the thing that the Americans did that mad the war unjustified. The war never just started the US just bleed more supplies in to the French then some CIA to do some work then by 1961 he sent some Green Berets in and by August 1964, he secured from Congress a functional (not actual) declaration of war: the Tonkin Gulf Resolution.
Then, in February and March 1965, Johnson authorized the sustained bombing, by U.S. aircraft, of targets north of the 17th parallel, and on 8 March dispatched 3,500 Marines to South Vietnam. Legal declaration or not, the United States was now at war. The multiple starting dates for the war complicate efforts to describe the causes of U.S. entry. The United States became involved in the war for a number of reasons, and these evolved and shifted over time.
Primarily, every American president regarded the enemy in Vietnam–the Vietminh; its 1960s successor, the National Liberation Front (NLF); and the government of North Vietnam, led by Ho Chi Min as agents of global communism. U.S. policymakers, and most Americans, regarded communism as the antithesis of all they held dear. Communists scorned democracy, violated human rights, pursued military aggression, and created closed state economies that barely traded with capitalist countries.
Americans compared communism to a contagious disease. If it took hold in one nation, U.S. policymakers expected contiguous nations to fall to communism, too, as if nations were dominoes lined up on end. In 1949, when the Communist Party came to power in China, Washington feared that Vietnam would become the next Asian domino.
That was one reason for Truman’s 1950 decision to give aid to the French who were fighting the Vietminh. Truman also hoped that assisting the French in Vietnam would help to shore up the developed, non-Communist nations, whose fates were in surprising ways tied to the preservation of Vietnam and, given the domino theory, all of Southeast Asia. Free world dominion over the region would provide markets for Japan, rebuilding with American help after the Pacific War. U.S. involvement in Vietnam reassured the British, who linked their post war recovery to the revival of the rubber and tin industries in their colony of Malaya, one of Vietnam’s neighbours. And with U.S.
aid, the French could concentrate on economic recovery at home, and could hope ultimately to recall their Indochina officer corps to oversee the rearmament of West Germany, a Cold War measure deemed essential by the Americans. These ambitions formed a second set of reasons why the United States became involved in Vietnam. As presidents committed the United States to conflict bit by bit, many of these ambitions were forgotten. Instead, inertia developed against withdrawing from Vietnam. Washington believed that U.S. withdrawal would result in a Communist victory–Eisenhower acknowledged that, had elections been held as scheduled in Vietnam in 1956, “Ho Chi Minh would have won 80% of the vote”–and no U.S.
president wanted to lose a country to communism. Democrats in particular, like Kennedy and Johnson, feared a right-wing backlash should they give up the fight; they remembered vividly the accusatory tone of the Republicans’ 1950 question, “Who lost China?” The commitment to Vietnam itself, passed from administration to administration, took on validity aside from any rational basis it might once have had. Truman, Eisenhower, and Kennedy all gave their word that the United States would stand by its South Vietnamese allies. If the United States abandoned the South Vietnamese, its word would be regarded as unreliable by other governments, friendly or not. So U.S. credibility seemed at stake.
Along with the larger structural and ideological causes of the war in Vietnam, the experience, personality, and temperament of each president played a role in deepening the U.S. commitment. Dwight Eisenhower restrained U.S. involvement because, having commanded troops in battle, he doubted the United States could fight a land war in Southeast Asia. The youthful John Kennedy, on the other hand, felt he had to prove his resolve to the American people and his Communist adversaries, especially in the aftermath of several foreign policy blunders early in his administration. Lyndon Johnson saw the Vietnam War as a test of his mettle, as a Southerner and as a man.
He exhorted his soldiers to “nail the coonskin to the wall” in Vietnam, likening victory to a successful hunting expedition. When Johnson began bombing North Vietnam and sent the Marines to South Vietnam in early 1965, he had every intention of fighting a limited war. He and his advisers worried that too lavish a use of U.S. firepower might prompt the Chinese to enter the conflict. It was not expected that the North Vietnamese and the NLF would hold out long against the American military.
And yet U.S. policymakers never managed to fit military strategy to U.S. goals in Vietnam. Massive bombing had little effect against a decentralized economy like North Vietnam’s. The Vietnam War was just as justified as the First World War; they didn’t have to do anything about it, but they did. People thought that war was a romantic and heroic thing to be involved in.
It wasn’t until TV brought the war into the lounge rooms of the Families that they started to see how horrible war is.