In his main work on international relations, The Twenty Years' Crisis, first published in July 1939, Edward Hallett Carr (1892–1982) attacks the idealist position, which he describes as “utopianism.” He characterizes this position as encompassing faith in reason, confidence in progress, a sense of moral rectitude, and a belief in an underlying harmony of interests. According to the idealists, war is an aberration in the course of normal life and the way to prevent it is to educate people for peace, and to build systems of collective security such as the League of Nations or today's United Nations. Carr challenges idealism by questioning its claim to moral universalism and its idea of the harmony of interests. He declares that “morality can only be relative, not universal” (19), and states that the doctrine of the harmony of interests is invoked by privileged groups “to justify and maintain their dominant position” (75).
Carr uses the concept of the relativity of thought, which he traces to Marx and other modern theorists, to show that standards by which policies are judged are the products of circumstances and interests. His central idea is that the interests of a given party always determine what this party regards as moral principles, and hence, these principles are not universal. Carr observes that politicians, for example, often use the language of justice to cloak the particular interests of their own countries, or to create negative images of other people to justify acts of aggression. The existence of such instances of morally discrediting a potential enemy or morally justifying one's own position shows, he argues, that moral ideas are derived from actual policies. Policies are not, as the idealists would have it, based on some universal norms, independent of interests of the parties involved.
If specific moral standards are de facto founded on interests, Carr's argument goes, there are also interests underlying what are regarded as absolute principles...