Every anniversary of the atomic bombings of Hiroshima and Nagasaki, two schools of thought square off. One says, the bombings were not necessary to end the war; the Japanese were close to surrender anyway. The other says remember Pearl Harbor, the Japanese militarists’ determination to fight to the end. But many questions remain unasked in this framework. Why was the U.S. Pacific fleet moved to Pearl Harbor in 1940? Why did Japan bomb it? When were Japanese forces first targeted, rather than Germany? The answers may surprise you. They are in a talk I gave at Santa Fe in 2012: see the video of it below. It’s about an hour. Links to some historical documents and additional information are provided below.

• Pearl Harbor was not a “sneak attack” in the sense that it was a total surprise to the United States. The Pacific fleet had been moved there in June 1940 to assert U.S. power in the Pacific. Admiral Kimmel, in charge of the fleet, noted in February 1941, nearly ten months before the attack that he felt that “a surprise attack (submarine, air, or combined) on Pearl harbor is a possibility.” So the bombing of Pearl Harbor in December 1941 was not a surprise in any military sense. The fleet’s vulnerability had been anticipated.
• Japan depended on the U.S. for 80 percent of its oil imports in 1940, making it very vulnerable to the oil embargo which began on August 1, 1941. It had to decide — pursue empire and get to Indonesian oil or give up its attempt to conquer China and other areas of Asia.
• In 1944, as a senator, Harry Truman had been frustrated and upset that he had not been allowed to send a personal military representative to the Hanford Site to determine whether the large expenditures there were wasteful or not. He gave in for the moment and agreed not to investigate, but warned Secretary Stimson in March 1944 that “[t]he responsibility … for any waste or improper action which might otherwise be avoided resists squarely upon the War Department.” Truman did not know about the Manhattan Project until after he became President in April 1945, upon the death of President Roosevelt.
• James Brynes, as director of the Office of War Mobilization, advised President Roosevelt in a March 3, 1945 memorandum that there should be an independent scientific investigation “to justify continuance of the project.’’ He warned that “if the project proves a failure, it will then be subjected to relentless investigation and criticism.”
• The concept that half-a-million lives may be saved by an early end to the war was mentioned in a note to Henry Stimson by an “economist” friend (my guess is that it was his cousin, Alfred Loomis, a wealthy Wall Street banker and amateur physicist) as an argument in favor of a conditional surrender policy. The main purpose of the suggestion of conditional surrender was to end the war before the Soviets entered, and thereby keep markets in Asia other than Formosa and Korea for the British and the Americans. Formosa and Korea were proposed to be ceded to Japan as part of the early end to the war.
• Stimson forwarded the letter to General Marshall for evaluation by his staff, which the general sent him on June 7, 1945. The General Staff considered the proposal “acceptable from the military standpoint, but its implementation on the terms suggested is considered doubtful.” Overall, the staff analysis leaned in the direction of terms that appear to add up to unconditional surrender. It rejected out of hand the suggestion that the invasion of Japan would cost half-a-million American lives. It stated that the estimate “under our present plan of campaign, is considered entirely too high” (underlining in the original; italics and bold added). General Marshall’s cover note to Stimson stated that he “general agreement” with the analysis.
• The war plan itself had three scenarios. Estimated deaths were in the range 25,000 to 46,000; injuries were in the range of 105,000 to 170,000 plus 2,500 to 4,000 missing in action. A few days later, on June 18, 1945, General MacArthur clarified that the “estimate was derived from the casualty rates in Normandy and Okinawa, the highest our forces have sustained….The estimate is purely academic and routine and was made for planning alone. I do not anticipate such a high rate of loss.”