1. My Lai Massacre (Vietnam War, 1968)

In 1968, U.S. troops killed over 500 unarmed Vietnamese civilians in the village of My Lai. This atrocity, involving women, children, and the elderly, was a flagrant violation of the Geneva Conventions’ protections for non-combatants. Despite the scale of the massacre, international outrage was slow to build, and accountability remained limited. The My Lai Massacre stands as a haunting reminder of how easily the rules of war can be ignored—and how the world sometimes hesitates to act.