Such reasoning will not impress anyone who fails to see how the brutality of the Japanese military could justify deadly retaliation against innocent men, women, and children. Truman doubtless was aware of this, so from time to time he advanced other pretexts. On August 9, 1945, he stated: "The world will note that the first atomic bomb was dropped on Hiroshima, a military base. That was because we wished in this first attack to avoid, insofar as possible, the killing of civilians."
Truman realized the kind of victims the bombs consumed is evident from his comment to his cabinet on August 10, explaining his reluctance to drop a third bomb: "The thought of wiping out another 100,000 people was too horrible," he said; he didn't like the idea of killing "all those kids."
By early summer 1945, the Japanese fully realized that they were beaten.
At the Potsdam conference, in July 1945, Truman issued a proclamation to the Japanese, threatening them with the "utter devastation" of their homeland unless they surrendered unconditionally.
To the Japanese, this meant that the emperor — regarded by them to be divine, the direct descendent of the goddess of the sun — would certainly be dethroned and probably put on trial as a war criminal and hanged, perhaps in front of his palace.103 It was not, in fact, the U.S. intention to dethrone or punish the emperor.
In May 1945, at the president's request, Herbert Hoover prepared a memorandum stressing the urgent need to end the war as soon as possible. The Japanese should be informed that we would in no way interfere with the emperor or their chosen form of government.
Pleas by some of the scientists involved in the project to demonstrate the power of the bomb in some uninhabited or evacuated area were rebuffed.
