A. Plan of Investigation
This investigation evaluates whether or not the dropping of the two atomic bombs on Hiroshima and Nagasaki was necessary to make Japan surrender unconditionally. To assess the extent to which the deployment of nuclear weapons affected the Japanese decision to surrender unconditionally and if Japan was already prepared to do this prior to the use of the atomic bombs. The details and motivations of the United States to drop the bombs are explored as well as Japan’s peace negotiations with the United States and their progress prior to the U.S. choosing to use the bombs. Actions of the United States and Japan not related to the end of World War 2 are not assessed in this investigation.
The two sources selected for evaluation, Code-Name Downfall: The Secret Plan to Invade Japan-And Why Truman Dropped the Bomb by Thomas B. Allen and Norman Polmar and Downfall: The End of the Imperial Japanese Empire by Richard B. Frank are evaluated for their origins, purposes, limitations, and values.
B. Summary of Evidence
On the 15th of June 1944 535 ships landed 128,000 U.S. Army personal on the island of Saipan. From Saipan B-29 bombers were in range of Tokyo. Imperative that they not allow this to happen the Japanese Vice Admiral attacked the U.S. Navy with about nine-tenths of Japan’s fighting fleet in the Battle of the Philippine Sea. Once the battle concluded the U.S. had lost 130 planes and 76 aircrew. Japan lost 450 planes, three carriers’, and 445 aircrew. The Japanese Navy’s carrier force was effectively destroyed. The U.S. took control of the island a short time later. More than 29,000 Japanese soldiers died defending the island. (Hoyt 297-312) On the 23rd of October 1944 the Battle of Leyte Gulf, the largest naval battle in world history began. With the goal of cutting Japan off from South East Asia and its oil supplies the U.S. Navy fought against the last remains of the Imperial Navy. By the battle’s end on October 26th Japan had lost 10,500 seamen, a fleet carrier, 3 light carriers, 3 battleships, 10 cruisers, 11 destroyers, and 500 planes. Japan’s once mighty Navy was no more. After this the Japanese were not able to carry out another significant Naval action for the remainder of the war. (Pape 123-168) Shortly afterwards the allies launched their invasion of the Philippines. On the 17th of April 1945 Mindanao, the last major island of the Philippines, was taken by the allies. In total 336,000 Japanese soldiers died defending The Philippines. (Hoyt 421-427) Within a few months of the fall of The Philippines Japan lost control of Burma and Borneo to the Allies. In total the Japanese military lost more than 41,000 soldiers defending the islands. After this the Japanese were effectively cut off from all of their major oil supplies. (Hoyt 437-449) With Japan’s foreign empire nearly decimated by the U.S. and its allies the U.S. turned to the Japanese Home Islands themselves. The Battle for the island of Iwo Jima ended on March 26th with total Japanese defeat. Of the approximately 21,000 Japanese defenders only 216 survived. On June 21st the Allies defeated Japan in the Battle of Okinawa (Feifer 145-163). 75,545 Japanese people lost their lives defending the island. This was to be the last major battle of World War Two. (Hoyt 478-487)
While in Europe the USAAF had only used precision bombing to limit civilian casualties the Air Force abandoned this policy while bombing Japan. The first raid using low-flying B-29 bombers carrying incendiary bombs to drop on Tokyo was on the night of February 24-25 1945 when 174 B-29s destroyed around 1 square mile of the city. Changing their tactics, on the night of March 9-10, 1945, a wave of 300 American bombers struck Tokyo. In the ensuing firestorm more than 100,000 Japanese civilians were killed and roughly a million were injured. Dropping nearly 1,700 tons of bombs more than 16 square miles were completely burned and more than a quarter of million...