A thought is built very often on specific distinctions, which reflect a singular pathway. Schmitt’s thought is above all an answer to Kelsen’s normativism even in the field of International Relations. The struggle between the two lawyers is about collective security organisation and the conception of international law (oversteping the primitivity of current law according to Kelsen, renewing with “european public law” for Schmitt), but also about the nature of international relations : integration of new actors and call on universum (Kelsen) ; focus on States and recognition of the permanent pluriversum (Schmitt).