For over two centuries the ideological opposition Capitalism vs. Communism has played a major role in the history of political ideas and movements, and for at least seventy years since 1917 it has also shaped international relations. The article examines the mutual representation that Capitalism and Communism gave of each other, and the current of emulation and sometimes convergence underlying their rivalry. It also stresses how both were changed through hybridization and reciprocal conditioning. The disappearance of one of the contestants in the late 20th century has
only apparently affected the importance of ideologies, and the triumph of one single concept, i.e. neoliberalism, does not prevent different kinds of fractures and cleavages from re-emerging.
Keywords: Capitalismo, Comunismo, Ideologie, Relazioni internazionali