Perpetual War for Perpetual Peace? Reflections on the Realist Critique of Kant's Project

In the last two decades, Kant’s theory of peace has played a crucial role in the fall of realism from its position as a leading theoretical option in debates regarding international relations. In a series of articles, Doyle noticed that Kant’s idea that “republics” (roughly, liberal democracies) are more prone to peace than dictatorships had received a striking confirmation by the last two hundred years of history (Doyle 1983a and 1983b). Doyle was very careful to interpret this historical statistic specifically as a refutation of the realist paradigm. Indeed, for him, the fact of a two century long peace among liberal states can neither be explained in terms of balance of power (the realist’s favorite explanation of peace) nor through a Marxist account. The realist school has launched a series of counterstrikes turning mainly on the attempt to explain the fact of the “liberal peace” in terms of prudence, alliances, strategic considerations. This paper focuses on a rather peculiar defensive move that charges Kant, or the contemporary Kantians, of providing a justification for a perpetual war against non-liberal states for the sake of perpetual peace. The first part discusses Kant’s first definitive article of Perpetual Peace. The second part deals with Waltz’s criticism and considers whether Kant can be really criticized for endorsing the use of violence for the sake of justice. Kant on this point shows a deep and interesting ambivalence that went largely unnoticed in the literature, but that creates a serious tension in his political thought. The final part suggests a line of thought that might lead to a satisfactory solution of this tension.