 Nevertheless, when it becomes a dogmatic enterprise, realism fails to perform its proper function. By remaining stuck in a state-centric and excessively simplified “paradigm” such as neorealism and by denying the possibility of any progress in interstate relations, it turns into an ideology. Its emphasis on power politics and national interest can be misused to justify aggression. It has therefore to be supplanted by theories that take better account of the dramatically changing picture of global politics. To its merely negative, cautionary function, positive norms must be added. These norms extend from the rationality and prudence stressed by classical realists; through the vision of multilateralism, international law, and an international society emphasized by liberals and members of the English School; to the cosmopolitanism and global solidarity advocated by many of today’s writers.