Analyzes policies of the Italian Communist Party (PCI) from the Second World War to the present, drawing on the author's knowledge of writings of Party leaders and debates in Parliament. Italian domestic politics have been crucially shaped by relations between the superpowers, and this had guided PCI decisions as they balance domestic opportunities for influence with constraints imposed by the international environment. Tension created in PCI by intrusion of U.S. and USSR factors contributed to the process that has moved the Party from hostility to NATO to sober acceptance of the Atlantic Alliance. Four factors influencing PCI's political approach to military affairs are: the Party's strategy for sharing in the governance of Italy and eventually building a socialist society; their Marxist-Leninist framework for analysis of international events; the Party's historical relationship with Tito's Yugoslavia; and desire for credibility of their commitment to NATO after many years of opposition.