During the inter war period, European Catholic authors exhibited two different approaches to the question of just war.
One approach was articulated at the “Fribourg Conventus,” a 1931 meeting of French, Swiss, and German theologians, whose subsequent declaration (Conventus de bello, published in 1932) called for a reformulation of Catholic teaching based on the premise that the traditional just‐war doctrine had been superseded by developments in international law. A competing approach was articulated by the Dutch Jesuit Robert Regout, who maintained that the just‐war doctrine could contribute to the formation of international law by providing a much‐needed normative foundation for the use of armed force by individual states in redress of their violated rights. After presenting these two approaches and explaining how they differ, this essay shows how the outlook of the Conventus de bello is reflected in subsequent papal statements on armed force—to the detriment of the traditional terminology of just war.
