On April 30, 1970, President Richard Nixon revealed to the nation that he was sending American forces into Cambodia to attack North Vietnamese sanctuaries. Nixon hoped to pressure North Vietnam into a peace deal that preserved South Vietnam—and American honor—after more than a decade of war. Although he announced further troop withdrawals from Vietnam at the same time, many Americans saw the campaign in Cambodia as an escalation of the war. On May 4, during a subsequent protest, four unarmed students at Kent State were shot and killed by the Ohio National Guard in what would become a pivotal moment in the antiwar movement.

Miller Center historian Marc Selverstone discusses the events that led to Nixon's decision—and the ensuing violence at Kent State.