The professed intention of NATO's intervention in Yugoslavia in March 1999 was to defend the human rights of an oppressed minority within a sovereign state. Many left-wing intellectuals claimed that to override national sovereignty was necessary for the salvation of the Kosovars, and that this reflects a new 'Kantian' conception of international relations in the post-Cold-War era, a conception which now remains to be actualized as a 'new international law of world citizens'. This paper seeks to refute these two arguments, that offer a moral interpretation of the war against Yugoslavia, not in order to question the project of 'perpetual peace' in its entirety, but to point out the need to reflect on its broader economic and political conditions, which are very far from being met.