As foreseen by Secretary Laird , fallout from the incursion was quick in coming on the campuses of America 's universities , as protests erupted against what was perceived as an expansion of the conflict into yet another country . On 4 May the unrest escalated to violence when Ohio National Guardsmen shot and killed four unarmed students ( two of whom were not protesters ) during the Kent State shootings . Two days later , at the University at Buffalo , police wounded four more demonstrators . On 15 May city and state police killed two and wounded twelve at Jackson State College ( now Jackson State University ) in Jackson , Mississippi . Earlier , on 8 May 100,000 protesters had gathered in Washington and another 150,000 in San Francisco on only ten days notice . Nationwide , 30 ROTC buildings went up in flames or were bombed while 26 schools witnessed violent clashes between students and police . National Guard units were mobilized on 21 campuses in 16 states . The student strike spread nationwide , involving more than four million students and 450 universities , colleges and high schools in mostly peaceful protests and walkouts
Kent State shootings
Kent State shootings
Cambodian campaign