During the late 1960s and early 1970s, Japan had a New Left protest cycle that paralleled those in western Europe and the United States. The Japanese New Left was separate from the parliamentary Japan Communist Party and drew many of its ideas from Japanese translations of the latest revolutionary New Left literature including works by Regis De Bray (1967), Che Guevara (1968, 1969), Rudi Dutschke (1968), Daniel Cohn-Bendit (1968), Howard Zinn (1968), Stokely Carmichael (1968), Eldridge Cleaver (1969), Alberto Bayo (1969), and Carlos Marighella (1970). Japanese New Left groups identified with student movements in the west and protested about similar issues, including opposition to the Vietnam War and American military bases in Japan, as well as tuition increases, overcrowding, and authoritarian regulations at universities. Frustrated by the Japanese government's intransigence in the face of huge protest demonstrations, they despaired of change through either electoral or street politics, and instead saw revolution as the only alternative. New Left street demonstrations steadily escalated into violent clashes resembling medieval battles. The students wore color-coded crash helmets emblazoned with names of their organizations, carried long fighting poles, and threw paving stones or firebombs at the police. They confronted squads of riot police wearing medieval style helmets, who battled the students with tall aluminum body shields and police batons, supported by water cannon trucks that sprayed fire hoses of water laced with tear gas at the students. At the peak of the protest cycle in 1968-69, Japanese authorities suddenly cracked down with mass arrests and prolonged incarcerations of thousands of students. This turned the tide, in part by producing splits within New Left groups.