This article discusses the legacy and limits of the Kantian paradigm in international relations. Contemporary Kantian reconstructions in international relations emphasise the positive aspects of liberal and institutional ideas, although they restrict themselves to the analysis of principles, and do not analyse what impedes the realisation of these principles. The first part of the paper analyses juridical principles that Kant established as conditions for peace: 1) Pacification of international order depends on democratisation of internal order; 2) Relations between states must be subject to international law; 3) Individuals must be considered as world citizens, according to cosmopolitan law. The second part shows how these principles have defined and oriented the pacifist movement as well as so-called "utopian-idealism" in the between-wars period. Further, it analyses realist criticism of those principles in post-war periods, according to which: 1) Democracy in internal order does not influence peace in international order; 2) Peace in international relations can be assured not by international law, but by military alliances; 3) Cosmopolitan ideals "moralise" international relations, transforming political conflict into a contention between "good" and "evil". Finally, it investigates how contemporary analyses orient themselves to Kantian principles, as opposed to realism (reason of state). This shows that this paradigm, while necessary, is not sufficient for analyses of international relations, since it does not consider the affirmation of principles in the analyses of hegemonic relations that characterize the international scene.
Kant; International Law; Cosmopolitanism; Human Rights