There is one point on which both sides in the present world conflict are agreed. Each may denounce the leadership of the other side, but neither supposes that a change in leadership would make any difference, because both believe that it is a conflict not of persons or governments, but of principles, or of systems of society. The commonly accepted explanation of the conflict, in short, is that the world is now divided between Communism and Capitalism. At the risk of seeming paradoxical it must be asked what this explanation explains, and whether, in fact, it does anything but provide convenient labels for the opposing forces. The implied assumption that states with differing economic systems must necessarily be hostile to one another is at least unproved, and goes against historical experience. It would be easier to explain the conflict as a religious war, and Communism certainly exhibits many of the features of a militant religion, but can we be quite content to dismiss Communists and capitalists as the Protestants and Catholics of the twentieth century? And if we are, can we find many religious wars in which secular and political interests did not provide as strong or stronger a motive than religion?