On September 2, 1945, V-J Day, Japanese officials aboard the USS Missouri formally surrendered to the United States, ending the Second World War.
Most Americans then and now believe that it was necessary for the U.S. to drop atomic bombs on Hiroshima and Nagasaki in order to induce Japanese leaders to surrender. This is not what most U.S. generals believed at the time.
General Dwight Eisenhower, in his memoirs, recalled a visit from Secretary of War Henry Stimson in late July 1945: “I voiced to him my grave misgivings, first on the basis of my belief that Japan was already defeated and that dropping the bomb was completely unnecessary, and secondly because I thought that our country should avoid shocking world opinion by the use of a weapon whose employment was, I thought, no longer mandatory as a measure to save American lives. It was my belief that Japan was, at that very moment, seeking some way to surrender with a minimum loss of ‘face.’” Eisenhower reiterated the point years later in a Newsweek interview in 1963, saying that “the Japanese were ready to surrender and it wasn’t necessary to hit them with that awful thing.”
In fact, seven out of eight top U.S. military commanders believed that it was unnecessary to use atomic bombs against Japan from a military-strategic vantage point, including Admirals Chester Nimitz, Ernest King, William Halsey, and William Leahy, and Generals Henry Arnold and Douglas MacArthur. According to Air Force historian Daniel Haulman, even Curtis LeMay believed “the new weapons were unnecessary, because his bombers were already destroying the Japanese cities.”
Admiral Leahy, Truman’s chief military advisor, wrote in his memoirs: “It is my opinion that the use of this barbarous weapon at Hiroshima and Nagasaki was of no material assistance in our war against Japan. The Japanese were already defeated and ready to surrender because of the effective sea blockade and the successful bombing with conventional weapons.”
That the Japanese were on the verge of defeat was made clear to the president in a top-secret memorandum from Secretary of War Henry Stimson on July 2, 1945. Stimson noted that Japan “has no allies,” its “navy is nearly destroyed,” she is vulnerable to an economic blockade depriving her “of sufficient food and supplies for her population,” she is “terribly vulnerable to our concentrated air attack upon her crowded cities, industrial, and food resources,” she “has against her not only the Anglo-American forces but the rising forces of China and the ominous threat of Russia,” and the United States has “inexhaustible and untouched industrial resources to bring to bear against her diminishing potential.”