It didn't seem possible. Four college students shot dead May 4, 1970, by Ohio National Guardsmen during a protest against the Vietnam War. The shootings at Kent State University would shock the nation and spark a mass student strike across the country, the only one in U.S. history. A photojournalism student's photograph of a teen girl crying in anguish over a victim's dead body would win the Pulitzer Prize and become a symbol of the antiwar movement...