Harry Stimson Operation Downfall Analysis

On April 24, 1945, U.S. Secretary of War Henry Stimson wrote to then-president Harry S. Truman: “I think it is highly important that I should have a talk with you as soon as possible about a highly secret matter.” In this confidential War Department file, Stimson would go on to explain that he had briefly mentioned this “secret matter” after Truman took office but had not pursued it because of the pressures on the new president in the context of the death of the previous president—Theodore Roosevelt—and the raging events of World War II. However, Stimson would go on to assert that this matter “has such a bearing on our present foreign relations and has such an important effect upon all my thinking in this field” that it was necessary that

However, despite Japan’s losing of its imperial territories and a large portion of its military force, it still had several million soldiers and thousands of planes. In order to achieve victory, it was becoming increasingly clear that a land invasion would be necessary. The proposed plan—codenamed Operation Downfall—was a full-scale, costly invasion of the Japanese mainland that consisted of two parts. The first of these was Operation Torch, an invasion of the southern island of Kyushu scheduled for November 1, 1945. The second was Operation Coronet, the invasion of the main island of Honshu scheduled for spring 1945. As they demonstrated in the battles of Iwo Jima and Okinawa, the Japanese forces had a capacity for strong resistance with U.S. forces suffering nearly a combined total of one-hundred thousand casualties in these two battles. Invading the Japanese mainland would undoubtedly be worse. Additionally, the Japanese had recognized several optimal landing sites and would assign high concentrations of troops in those places. With these factors in mind, casualty estimations, despite being varied, were grim. A study by the Joint Chiefs of Staff placed estimates at 1.2 million casualties, and former president Herbert Hoover made conservative estimates of five-hundred thousand to one million. Furthermore, additional allied deaths would occur upon invasion; Hisaichi Tesuachi, a Japanese Army Marshall, had promised the execution of all one-hundred thousand allied prisoners of war if the Americans invaded. Finally, Operation Downfall would further draw out the length of the war. The war-weary Americans—in their fourth year of total—were eager for the end of the war and wanted victory as soon as possible. With these factors in mind, the use of the atomic bomb presented a viable alternative. In contrast with the planned Operation Downfall, the atomic bomb was quicker, less costly, and could