On 17 March 1939, Italian-born physicist Enrico Fermi (who had fled from Mussolini’s Fascist Italy to the United States in 1938 for the safety of his Jewish wife) gave a briefing in Washington, D.C., (attended by some U.S. They also recognized the dire danger of this process in the hands of Nazi Germany. Physicists around the world quickly grasped the revolutionary implications of this discovery, particularly the enormous energy that would be released in a chain reaction of splitting atoms. (Meitner would never really get due credit for her key role.) Frisch reported the findings to his boss, eminent Danish physicist Niels Bohr, who in turn shared it with American physicists. Physicists Lise Meitner and her nephew Otto Frisch (both Austrian-born Jews who had recently fled from Berlin to Stockholm and Copenhagen, respectively) analyzed the results and determined that the uranium atom had split in two, and they estimated the significant energy released, which Meitner and Frisch reported in a paper in January 1939 that explained the physics of the process, coining the term “fission.” Due to the anti-Semitic environment in Nazi Germany, Hahn and Strassman published their results without acknowledging Meitner and Frisch’s contribution. In December 1938, German chemists Otto Hahn and Fritz Strassmann discovered that a collision of a neutron with a uranium nucleus had the unexpected result of producing barium as a byproduct. The Marianas Islands were the fastest and only really viable option to bring Japan within range of U.S. Trying to conduct operations from the Aleutians was a non-starter, and the Soviet Union would not agree to enter the war against Japan until after the defeat of Nazi Germany. An earlier attempt to bomb Japan with B-29s flying from bases in China (Operation Matterhorn) had been a costly failure, reaching only targets in the far south of Japan at a high cost in B-29 aircraft (128, mostly due to operational causes), and that was before the massive Japanese Ichigo offensive in China in late 1944 rolled up the bomber airfields. Navy, there would have been no B-29 bomber bases in the Marianas Islands in range of Japan. Navy contribution is that without the U.S. Only Emperor Hirohito had the moral authority to convince the Japanese military to surrender, and it was the atomic bombs that convinced him.Īn obvious U.S. Blockading and starving 100 million Japanese was hardly a more “humane” option and not likely to convince the Japanese military diehards to give up. Those who claim otherwise need to study up on Saipan, Iwo Jima, and Okinawa. and Japanese, military and civilian-than the atomic bombs. An invasion of Japan would have cost far more lives-U.S. The B-29 firebombing raids that began in March 1945 killed more Japanese civilians than the atomic bombs (as many as 100,000 civilians in the first firebombing raid on Tokyo alone on 9–10 March 1945). Finally, this H-gram is not intended to be a discussion of the morality of using atomic weapons, other than to note that from a safe remove, it is easy for armchair generals and historians to judge the decisions made by senior political and military leaders when every option was incredibly bad. Navy personnel performed some of the most vital roles in the operation.
Army, the Army Air Force, or the civilian scientists and engineers. This H-gram is not intended to be a comprehensive history of the Manhattan Project, nor is this H-gram trying to diminish the critical roles of the U.S.