Final answer:
During the Kent State shootings, unarmed students protesting the Vietnam War were fired upon by the National Guard, leading to four deaths. The reasons for the shooting remain unclear, and it highlighted the nation's divide over the war.
Step-by-step explanation:
On May 4, 1970, the Kent State shootings occurred during a period of widespread antiwar demonstrations in the United States. The Ohio National Guard was called in after students at Kent State University set fire to the ROTC building. The confrontation escalated, and the National Guard used tear gas to disperse the demonstrators. For unclear reasons, guardsmen fired into a crowd of students, resulting in the death of four and wounding nine. The students were protesting President Nixon's announcement of the Cambodia Campaign and were part of national unrest. There were reports of students throwing rocks, but unequivocally, most of the protesters were unarmed. This tragic event, often referred to as the 'Kent State Massacre,' highlighted the deep divisions in the country and marked a significant moment in the history of protests against the Vietnam War.