Alexander Wendt set out to show that (Neo)Realists are wrong: it is not an unchanging fact that the international realm is a self-help system. Rather, the international environment is created and recreated in processes of interaction. As the way states act may change, so can the international system. The key move in this argument is that actors' identities are not given but are developed and sustained or transformed in interaction (see ISC 48; A; STIP). This is, he argues, what sets a constructivist approach apart from the ‘rationalism’ of mainstream approaches to the study of international politics. Rationalists may admit that behaviour changes but they consider the properties of actors, such as their identity, external and prior to the process of international politics. The concept of identity is employed to establish the difference from rationalism. The constructivist alternative presented by Wendt revolves around the construction of identity.

Wendt's work is addressed to the ‘mainstream’ (see A 397, n. 21; STIP). In his influential ‘Anarchy Is What States Make of It’, he locates his approach, with respect to the debate between Realists and liberals, where both sides share a commitment to rationalism and thus the assumption that agents' identities and interests are given. In Wendt's view, there is, however, a tradition of ‘strong’ liberal scholarship concerned with complex learning and thus changes in interests and identities (A 393).