From the middle of the 1930s to the end of the Second World War, Kelsen devoted most of his scholarly attention to the question of political reform of the institutional structure of the international legal community. Before the outbreak of the Second World War, his publications dealt with the discussions about the reform of the League of Nations, which had been going on since the mid 1930s. Later, Kelsen's work on this topic made a contribution to the debate over a new, peace-securing world organization, which got under way during the war. At the center of these publications stood the de lege ferenda call for the establishment of an international court charged with compulsory adjudication. Kelsen's blueprint of a constitutive document for the new world organization made the court the central organ, whose decisions would have to be enforced by a council of the great powers. The creation of such a court, rendering binding decisions, was the institutional core of Kelsen's cosmopolitan project.

Peace through compulsory jurisdiction

Having witnessed two world wars, Kelsen saw in the rule of law in international relations, secured by courts rendering binding decisions, the only way to a more peaceful world order. The state of peace pursued by compulsory jurisdiction did not mean for Kelsen the complete absence of violence, but merely a state of relative peace. In that sense Kelsen set himself apart from a “utopian pacifism,” which he regarded as a serious threat to international politics.