At the close of World War I two schools of thought about the future conduct of international relations emerged into plain view. On the one hand, the traditionalists presumed that the principles and practices of pre-1914 diplomacy could and should be sustained. This implied a routine of continual competition among the sovereign nation states, the anarchy of which was mitigated only by the collective fear of hegemony by one state (the mechanism of the balance of power) and by a sense of belonging to a common civilization (the old Concert of Europe). Tacitly accepted as the final arbiter of vital questions was the instrument of war. On the other hand, the First World War had provided ample grounds for a swingeing critique of
Realpolitikwhen practised in an age of mass armies and technological warfare.