to Rotblat's decision to leave the project later on, because unlike many scientists, he was concerned with how his work would be utilized. When working on the scattering of neutrons in uranium fission, Rotblat realized that this process could eventually create an unprecedented large scale explosion, thus making an atomic bomb plausible. Rotblat was frightened with this discovery and immediately shoved the thought out of his mind “like a person trying to ignore the first symptom of a disease in the hopes that it will go away.” (Rotblat 16). Rotblat was obviously facing scruples in relation to his discovery and the plausibility of the atom bomb. In January 1944 Rotblat joined the Manhattan Project in Los Alamos, finally committing himself entirely to the construction of the bomb. This was the point in Rotblat's life where his position in relation to creating the bomb was the clearest; he was ready to contribute to the project in order to guarantee that the US devised the bomb before Germany. By joining the project, Rotblat decisively made up his mind, believing that if Hitler won the war, science as he knew it would vanish anyway (Veys 456). He still suffered with the burden of contributing to the creation of a weapon of mass destruction, but he was convinced it was the right choice.
Not soon after he joined the project, Rotblat began to realize that it was highly improbable that Germany, who was designating all its resources to the war and was also under constant bombardment, would be able to replicate the US's efforts in creating the nuclear bomb. He thus began to question his participation in the Manhattan Project, but decided to remain in the project to guarantee that the Allied powers would create the bomb before the Nazis (Veys, 461). At this moment Rotblat's thoughts and actions began to indicate his change in position, as he went from a position of certainty to a position of doubt on whether it was the correct choice to remain in the project. This all contributes to showing how Rotblat's mentality on the subject of participating or not on the project constantly oscillated.
Tortured by his scruples, Rotblat searched for clarity in the words of other scientists. He discussed his moral dilemmas and the implications of his work with Niels Bohr, another scientist in who felt uncertain about the morality of his work (Chiabotti 134). Both scientists were afraid of the ramifications of the weapon, and were even alert to the devastating consequences of an arms race between East and West (Rotblat 18). At this point in time Rotblat was demonstrating a change in attitude towards his work in the project. In January 1944 when he joined the project, he was determined it was the right decision. Now that he was involved in creating the nuclear bomb, Rotblat was beginning to doubt his decision, and was beginning to believe it would be best if the bomb were never created. His conversation with Bohr largely indicated a change in Rotblat's position towards the creation of the weapon.
The critical turning point on Rotblat's decision to work on the bomb was at a dinner with James Chadwick and General Groves. At this dinner Groves pronounced that the real purpose of creating the weapon was to subdue the soviets (Rotblat 18). Rotblat felt indignant to this comment as he could not believe the weapons intended use was against an allie who at the very moment was sacrificing thousands of lives for the same cause (Rotblat 19). This factor, together with the growing evidence that Germany was not going to succeed in building the bomb, led Rotblat to abandon the project in December of 1944 (Veys 463). Rotblat's decision to leave the project and return to Britain marked his position in relation to the nuclear bomb. He left because he no longer believed its creation was necessary; in fact he believed it was essential that the bomb were not built. Rotblat was perhaps the only scientist at the time fully aware of the consequences of the bombs existence, and was now fully committed to ensuring the non-proliferation of the weapon.
After leaving the project, Rotblat devoted his life to clarifying the health impacts of radiation and to reducing the dangers posed by nuclear weapons. In 1955, ten years after his leave, he signed the Russell-Einstein Manifesto, being the youngest of its eleven signers. The manifesto called upon scientists to gather and discuss about the perils of the atomic bomb (Holden 633). Rotblat’s decision to sign the manifesto revealed his full determination to spread awareness of the weapons and his attempt to someday make them obsolete. At this point Rotblat had shifted from a scientist involved in the Manhattan Project and in the creation of the bomb, to one of the leaders of the movement against the atomic weapons.
Rotblat was instrumental in establishing the Pugwash Conferences on Science and World Affairs, which held more than 300 conferences, symposiums, and workshops on arms control and peace building, since its inauguration in 1957 (Holdren, "Joseph Rotblat" 633). The Pugwash Conferences were so effective they managed to assemble scientists and public figures from both sides of the Iron Curtain, during the Cold War, to discuss the troublesome science and security issues of the time (Holdren, "Joseph Rotblat" 633). The Pugwash Conferences were not open to public media in order to guarantee that sincere and in depth conversations be held. These meetings are credited for laying the foundations for the Nuclear Non-Proliferation Treaty, the Partial Test Ban Treaty, the Anti-Ballistic Missile Treaty, the Biological Weapons Convention, and the Chemical Weapons Convention. Joseph Rotblat was the organization's first secretary general (1957 to 1973) and later served as its president (1988 to 1997) (Holdren, "Pugwash" 6). This was the leading organization against the proliferation of nuclear bombs at the time, and Rotblat's involvement in it clearly indicates his urge to reduce the use of the weapons. Rotblat's high positions in the organization made him largely responsible for these achievements, displaying his commitment to reducing the bombs' impact.
Rotblat also became one of the founders of the Atomic Scientists Association, which until today is an association established to warn the public of the threats of weapons of mass destruction (Holdren, "Joseph Rotblat" 633).
He was clearly involved in numerous attempts to diminish the risk posed by atomic bombs.
In 1995 Rotblat was awarded half of the Nobel Peace Prize for, as quoted by the Norwegian Nobel Committee, "efforts to diminish the part played by nuclear arms in international affairs and in the longer run, to eliminate such arms." (qtd. In Holdren, "Joseph Rotblat" 633).
Rotblat has certainly positioned himself in a variety of ways in relation to the nuclear bomb's creation. In his early years, in the midst of World War II, he believed in the creation of the bomb, and even worked in the Manhattan Project. In his work he began to realize that maybe the atomic bomb should not be created. He faced torturous moral dilemmas, but decided it was best if the weapon were not created, thus abandoning his work on the bomb. Later on, with the creation of the weapon, Rotblat positioned himself entirely against the bomb, and did everything in his power to reduce its danger and prevent nuclear proliferation. His actions elucidated his position towards the creation of the bomb, which he ultimately decided should be contained by all measures. In Rotblat's article he clearly states that the prime effort of civilization should be to prevent nuclear war (Rotblat 19), thus confirming his complete change in position towards the bomb's
creation.