The My Lai Massacre: Causes and Significance Video

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  • 0:01 Why My Lai?
  • 1:51 Events of the Day
  • 3:14 Initial Report & Investigation
  • 4:50 Lesson Summary
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Lesson Transcript
Instructor: Adam Richards

Adam has a master's degree in history.

The My Lai Massacre was a deviation from the normal military campaigns of the United States in the Vietnam War. Learn about the atrocity including its background, the events and its importance within the war in this lesson.

Why My Lai?

One of the more disheartening events of the Vietnam War occurred on March 16, 1968, when American soldiers from the Americal Division, officially known as United States Army C Company, 1st Battalion, 20th Infantry Regiment, 11th Brigade, 23rd Infantry Division, marched into the hamlet of My Lai, located in the village of Son My, and brutally executed hundreds of alleged members and supporters of the 48th Battalion of the National Liberation Front, or NLF, which was the insurgent arm of North Vietnam. Regrettably, many of the deaths, in what became known as the My Lai Massacre, were not that of enemy soldiers but of nonaligned Vietnamese citizens.

Many questioned why the American-led execution occurred at My Lai. The general answer was that many soldiers within this specific platoon had been aggravated by the psychological toll the war had created. These men had survived booby traps, ambushes and guerrilla conflict orchestrated by the 48th NLF Battalion since arriving in Vietnam in 1967. When the unit had the opportunity to retaliate for the months of frustration, it did so with fierce yet senseless vengeance.

The massacre at My Lai held importance for a number of reasons. First, upon learning of the event in 1969, the American anti-Vietnam War movement ballooned with new members and support. The movement had struggled to remain united during 1968, but the My Lai Massacre served as a rallying point for antiwar opposition.

Second, original military reporting contended that the unit had eliminated dozens of enemy soldiers and hailed the skirmish at My Lai as a significant achievement. When the real story was leaked, the credibility gap, which is the conflict in reporting between officials in Washington, D.C., and the media in Vietnam, widened. Finally, the event sparked a reassessment of American personnel in Vietnam, including their psychological profile, training and time in the field.

Events of the Day

The My Lai Massacre stemmed from previous events in the Vietnam War. The Tet Offensive, which occurred during the first two months of 1968, was a large military invasion of South Vietnam by North Vietnam. After two months of constant warfare, the United States and South Vietnamese had repelled a significant amount of the enemy from South Vietnam.

Many American units were then ordered to go on the offensive against remaining pockets of enemy personnel throughout the country. The Americal Division was sent to Son My, the staging ground of the 48th Battalion of the NLF, with the intention of engaging in search-and-destroy operations to eliminate the unit.

Lieutenant William Calley led the Americal Division into My Lai on March 16 and ordered his men to eliminate all suspected members of the NLF. The search-and-destroy mission to abolish the enemy quickly turned into a rampant wave of murder and destruction. After-action reports indicated that many soldiers within the unit fired upon unarmed and unsuspecting women, children and the elderly.

It should be noted that there were several soldiers who defied orders and tried to stop the killings. Regardless, many Vietnamese were gathered and executed in ditches, homes were burned and crops destroyed. By mid-afternoon, over 300 civilians had perished, according to the preliminary body count by the Army (the Vietnamese reported that over 500 had died). Scant evidence was ever found that would have linked the Vietnamese civilians in My Lai to the NLF.

The Initial Report and Investigation

Initial reports of the actions at My Lai provided by the Military Assistance Command, Vietnam, or MACV, the primary military command structure for American forces during the war, indicated a successful search-and-destroy operation that had eliminated dozens of suspected enemy soldiers. Even Calley maintained that he only opened fire when he believed enemy soldiers had been identified. However, several reports surfaced that challenged the authenticity of the MACV and Calley's position.

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