On May 4, 1970, National Guardsmen fired into a crowd of unarmed students protesting the Vietnam War at Kent State University in Ohio, killing four students and injuring nine others. The incident, known as the Kent State Massacre, became a turning point in the antiwar movement, sparking a wave of protests and demonstrations across the United States. The tragic event galvanized opposition to the war and fueled the growing sentiment that the government was using excessive force to suppress dissent.