Opposition to Development
After the atomic bombings of Japan, many scientists at Los Alamos rebelled against the notion of creating a weapon thousands of times more powerful than the first atomic bombs. For these scientists, the question was partly technical, partly moral. First, the weapon design was still quite uncertain and unworkable; second, they argued that such a weapon could only be used against large civilian populations and could thus only be used as a weapon of genocide. Many scientists urged that the United States should not develop such weapons and set an example towards the Soviet Union. On the other hand, promoters of the weapon, including Edward Teller, Ernest Lawrence and Luis Alvarez, argued that such a development was inevitable, and to deny such protection to the people of the United States-especially when the Soviet Union was likely to create such a weapon themselves-was itself an immoral and unwise act.
J. Robert Oppenheimer, who was now head of the General Advisory Committee of the successor to the Manhattan Project, the Atomic Energy Commission, presided over a recommendation against the development of the weapon. He reasoned that the technology's success seemed limited at the time and not worth the investment of resources to confirm whether this was so. He also believed that the U.S.'s atomic forces would be more effective if they consisted of many large fission weapons (whereby multiple bombs could be dropped on the same targets) rather than massive super bombs for which there were a relatively limited number of targets large enough to warrant such a development. Furthermore, were such weapons developed by both the U.S. and the USSR, they would be more effectively used against the U.S. than by it, as the U.S. had far more regions of dense industrial and civilian activity that would serve as ideal targets for the large weapons than the Soviet Union did.