The detonations of atomic bombs over two major Japanese cities and the development of nuclear weapons stirred many responses from intellectuals. Immediate responses were those of shock and fear, constituting a distinct feeling of dystopianism in what earlier research has described as a utopian moment. This article assesses how Karl Jaspers, Denis de Rougemont and Bertrand Russell responded to the bomb, from the years 1945–1958, drawing upon the devices of transnational and conceptual history. They regarded the Second World War and the nuclear armament as results of nation state sovereignty and pleaded for international law and delineations of national sovereignty. The responses underwent three different phases, while they continued to share the common threats of communism and Soviet totalitarianism. In looking at Jaspers, De Rougemont and Russell, we are able to see an internationalism that argued from the standpoint of a liberal order which was increasingly fuelled by anti-communism. In several respects, their responses to the atomic bomb represented a major strand of Western European internationalist thinking during the post-war period.
The arrival of the atomic bomb into the discussion about international relations was duly noted by early post-war politicians, scholars and intellectuals. In the autumn of 1945, the leaders of United States, Britain and Canada suggested an Atomic Energy Commission to develop an international system in order to control the technology and ensure that it would only be utilised for civil purposes. Scholars of international law were eager to discuss the issue. Within days after the bombs were dropped on Japan, the Danish physicist Nils Bohr wrote in a newspaper that no defence was possible against that weapon; only worldwide regulation could save man and simultaneously provide the eternal source of atomic energy. He was vital to the outcome of the Manhattan Project, as was its leader Robert Oppenheimer and its founder Albert Einstein, who also took stands against the bomb, warning that it could extinguish all life on Earth. Both attested to the necessity to safeguard against using the bomb by establishing supranational control.