Ethnic, nationalist, and religious conflicts and debates about international intervention have been central global preoccupations of the past hundred years. Such debates, this volume argues, were first framed in their modern form during the interwar period, when a "Modernist break" (akin to that in literature, philosophy, and the arts) transformed the way such conflicts were viewed. Internationalists began to cast identity-based claims -- whether those of anti-colonialists or European separatists -- not only as mortal dangers to international order but as indispensable to its revitalization....

Although portrayed as a liberal law of co-existence of and co-operation between states, international law has always been a welfarist law, too. Emerging in eighteenth-century Europe, it soon won favour globally. Not only did it minister to the interests of states and their concern for stability, but it was also an interventionist law designed to ensure the happiness and well-being of peoples. Hence international law initially served as a secularised eschatological model, replacing the role of religion in ensuring the proper ordering of mankind, which was held to be both one and divided. That...