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The Vietnam War

KC‑8.1.I.B.ii (KC)
Unit 8: Learning Objective I
WOR (Theme)
Learn about the war that enmeshed the United States in a battle against communism in Southeast Asia for more than twenty years.


  • The Vietnam War was a prolonged military conflict that started as an anticolonial war against the French and evolved into a Cold War confrontation between international communism and free-market democracy.
  • The Democratic Republic of Vietnam (DRV) in the north was supported by the Soviet Union, China, and other communist countries, while the United States and its anticommunist allies backed the Republic of Vietnam (ROV) in the south.
  • President Lyndon Johnson dramatically escalated US involvement in the conflict, authorizing a series of intense bombing campaigns and committing hundreds of thousands of US ground troops to the fight.
  • After the United States withdrew from the conflict, North Vietnam invaded the South and united the country under a communist government.

Origins of the war in Vietnam

The origins of American involvement in Vietnam date back to the end of the Second World War, when the Vietnamese were struggling against the continued French colonial presence in their country. Ho Chi Minh, the leader of the Viet Minh (Vietnamese Independence League) and the founder of Vietnam’s Communist Party, successfully blended nationalist, anti-French sentiment with Marxist-Leninist revolutionary ideology. In 1954, after a prolonged guerrilla war to liberate Vietnam, the Viet Minh captured Dien Bien Phu, and decisively routed the French.start superscript, 1, end superscript
Map showing the division between North Vietnam and South Vietnam. The two countries were divided along the 17th Parallel, also known as the Line of Demarcation.
Map of Vietnam. The 17th Parallel indicates the boundary separating North and South Vietnam following the peace negotiations in Geneva in 1954.
In peace negotiations at Geneva, the decision was reached to divide Vietnam into northern and southern halves. The communists, headed by Ho Chi Minh, would govern the northern half, with its capital at Hanoi, while South Vietnam, with its capital at Saigon, would remain non-communist. The Soviet Union and the People’s Republic of China supported the north, while the United States was determined to maintain an independent, non-communist South Vietnam.
In December 1960, the National Liberation Front, commonly called the Viet Cong, emerged to challenge the South Vietnamese government. A civil war erupted for control of South Vietnam, while Hanoi sought to unite the country under its own communist leadership. The Second Indochina War began in earnest with the US commitment to prevent the communists from overrunning South Vietnam. In spring 1961, the administration of John F. Kennedy expanded US support for the South Vietnamese government, including an increase in US military advisers, the doubling of military assistance, and authorization of the use of napalm, herbicides, and defoliants.squared
The escalating US involvement in Southeast Asia was driven by the logic of the domino theory, which contended that the falling of one country to communism would result in other surrounding countries succumbing to communism, much as one toppled domino will take down others in a row. The containment strategy, laid out by George Kennan in the Long Telegram, dictated that the United States do everything in its power to prevent the spread of communism. US officials believed that if South Vietnam fell to communism, so would the surrounding countries of Indonesia, Thailand, Burma, Malaysia, Laos, and Cambodia.

Lyndon Johnson and the war in Vietnam

In August 1964, the US government received word that two North Vietnamese torpedo boats attacked US destroyers in the Gulf of Tonkin. President Lyndon Johnson requested authorization from Congress for the use of military force, resulting in the Gulf of Tonkin resolution, which laid the groundwork for the full-scale US military commitment to Vietnam. The resolution declared the support of Congress for “all necessary measures to repel any armed attack against the armed forces of the United States and to prevent further aggression.”cubed
Johnson was motivated by both domestic political and international balance of power considerations. He fully subscribed to the domino theory and to the containment strategy, and also feared appearing weak in the eyes of his domestic political opponents.start superscript, 4, end superscript
In 1965, Johnson dramatically escalated US involvement in the war. He authorized a series of bombing campaigns, most notably Operation Rolling Thunder, and also committed hundreds of thousands of US ground troops to the fight. Fearful that the war would jeopardize his domestic agenda, Johnson concealed the extent of the military escalation from the American public.start superscript, 5, end superscript
President Lyndon Johnson awards a medal to an American soldier during a visit to Vietnam in 1966. Image courtesy Wikimedia Commons.
The 1968 Tet Offensive, a bold North Vietnamese attack on the south, convinced many US officials that the war could not be won at a reasonable cost. Heightened opposition to the war was one of the major factors in Johnson’s decision not to run for re-election in 1968.

Richard Nixon and Vietnam

Richard Nixon campaigned for the presidency with a “secret plan” to end the war in Vietnam. Once in office, his administration sought to achieve “peace with honor.” Nixon ultimately expanded the war into neighboring Laos and Cambodia, while simultaneously encouraging the “Vietnamization” of the war effort, which entailed the gradual withdrawal of US troops and an increasing reliance on the South Vietnamese armed forces. By the end of 1969, the number of American troops in Vietnam had been cut in half.start superscript, 6, end superscript
The Paris Peace Accords established the terms according to which the last remaining US troops in Vietnam would be withdrawn. In 1975, the North Vietnamese finally achieved the objective of uniting the country under one communist government. The Socialist Republic of Vietnam was formally established on July 2, 1976, and Saigon was renamed Ho Chi Minh City. Though the outcome of the war was a clear defeat for the United States, the countries surrounding Vietnam did not subsequently fall to communism, demonstrating the flawed reasoning of the domino theory.
The war in Vietnam had lasting consequences for US foreign policy. Congress passed the War Powers Act in 1973, in a clear attempt to reassert a measure of control over the making of foreign policy and to impose constraints on presidential power. For well over a decade, American public opinion was hostile to the idea of foreign interventions. This was known as the “Vietnam syndrome,” and it entailed an unwillingness to become bogged down in foreign wars in which American national security interests were unclear.

What do you think?

Why did the United States become involved in Vietnam?
What were the assumptions underlying the US involvement in Southeast Asia? Were they correct?
Was the war in Vietnam a civil war or a global Cold War confrontation?

Want to join the conversation?

  • leaf orange style avatar for user Jeff Kelman
    "...John F. Kennedy expanded US support for the South Vietnamese government, including an increase in US military advisers, the doubling of military assistance, and authorization of the use of napalm, herbicides, and defoliants..."

    I googled the word "defoliant" and learned that it is effectively a type of chemical that is designed to kill off all the leaves on plants. What would be the purpose of using a chemical like this? Also, I have heard of the horrid "Agent Orange" in past history classes, and learned that it did horrible things to the people that were near or directly under where it was sprayed. Did JFK, or the government at large, know that "Agent Orange" or other "defoliants" would have had these negative effects on human beings, prior to authorizing their use?
    (26 votes)
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  • mr pants teal style avatar for user Jacob, Samour
    1) It became involved in Vietnam because of the fear of the domino theory potentially happening in Vietnam.
    2) That if Vietnam became communist the area around it would also become communist. They were wrong because when Vietnam eventually became communist the area around it didn't.
    3) It was originally a civil war but it ended up becoming a global Cold War confrontation especially the reasoning for the involvement of the US.
    (14 votes)
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  • leaf orange style avatar for user Jeff Kelman
    How come there was a "Vietnam Syndrome", but it would appear as if there hasn't been any sort of "Middle East" Syndrome" (large scale mass resistance to government foreign interventions) related to all of the United States' involvement in conflicts in Iraq/Afghanistan etc.?
    (4 votes)
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  • aqualine ultimate style avatar for user Bill Vu
    If the vietnam war was about the north spreading communism articles say that vietnam battled america instead of saying that the south battled the north alongside america , so is it saying that america fought the whole vietnam gov. or is it saying that the south fought the north with america or did america never ally with the south of vietnam?
    (4 votes)
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  • leaf red style avatar for user Carla Cristina Almeida
    I have a question about the draft: how were the young man selected? or did they just enlist and were picked randomly? was it education, the size of the family etc?
    (3 votes)
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    • piceratops ultimate style avatar for user Kim Kutz Elliott
      From the author:All American men had to register for the draft at age 18. When a draft took place, it randomly selected men between the ages of 18 to 25. One caveat to this, however, was that men who were in college could be excused from the draft. This meant that often wealthier men (who could afford college tuition) could avoid being sent to Vietnam, while men from poorer families could not avoid it.

      It was also possible to avoid the draft by applying for the status of a Conscientious Objector, someone who objected to war so strongly that they could not fight in it. Generally to be granted this exemption a person had to have been extremely active for many years in anti-war movements or with a faith that condemned violence.
      (11 votes)
  • blobby green style avatar for user armor.pro57
    When the United States technically "lost" the war, did it seem like an utter waste of time and resources? How did the American public react when they heard the news?
    (5 votes)
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    • aqualine tree style avatar for user David Alexander
      Question 1: "did it seem like an utter waste of time and resources?" Yes, to me (who served in Vietnam with the US Army for 11 months in 1970) it seemed like an utter waste of time and resources. Other people may have felt differently. I can only speak for myself.

      Question 2: "How did the American public react when they heard the news?" There is no "unified American Public". Different persons reacted differently. Many parents of up-and-coming potential soldiers were grateful that their sons and daughters wouldn't have to serve in a war. Many adventurous young people regretted that they couldn't go overseas and play with guns. Many industrialists (and stockholders) who had profited from a war economy regretted the loss of business. Many broken veterans felt that their brokenness had been unredeemed.
      (5 votes)
  • starky tree style avatar for user Zob Rombie
    The main reason the war escalated so badly and quickly was because LBJ and Nixon right? Would have Kennedy have done equally as bad or worse had he had the chance? Or would he have gone in a quote “better” direction based upon how he handled other things as president? Were LBJ and Nixon bad decision makers or was it just too much to handle?
    (6 votes)
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  • boggle blue style avatar for user Angela Hilario
    I've read that the Vietnam War is referred to as the 'American War' (in full, War Against the Americans to Save the Nation) in Vietnam. Would anyone know as to why it is called this?
    (2 votes)
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  • leafers sapling style avatar for user Sean Rim
    Agent Orange not only effected Vietcong but also US Infantry so that was more horrid than anything I could think of of
    (2 votes)
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  • starky tree style avatar for user zander musser
    "In August 1964, the US government received word that two North Vietnamese torpedo boats attacked US destroyers in the Gulf of Tonkin" i've herd that this may not be true, that either the us destroyers attacked the vietnamese boats, or that nothing happened. does anyone have any further information.
    (2 votes)
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    • aqualine tree style avatar for user David Alexander
      A US Navy Warship, the USS Maddox, was in international waters in the Gulf of Tonkin conducting spy operations on the sovereign nation of North Vietnam. Those operations would support the sovereign nation of South Vietnam, with which North Vietnam was at war. On August 2nd, in a defensive move, the navy of North Vietnam sent torpedo boats to drive away the US Navy ship. Nobody disputes this.

      Two days later (on August 4) there was a storm out there. Some sonar operators on the ship generated messages that the ship was under attack, and a message was sent. Soon afterward, the captain of the ship withdrew that report, citing the weather and the "over zealous" character of those sailors.

      The executive branch of the US government combined the August 2 report with the FIRST August 4th report (which they it knew had been withdrawn) and made no mention of the withdrawal message, and sent a message to the congress that a US Warship (which was not described as engaged in spy activities) had been attacked by a hostile state. The congress then passed a resolution that opened the way to the escalation that resulted in the Vietnam war, in which millions of Vietnamese lost their lives and tens of thousands of young Americans died, too.
      (4 votes)