
Evaluations of the Hiroshima bombing should be weighed against evasions of the Nanking Massacre. Whatever we think of Hiroshima, we should not paint it as a morally more reprehensible event than Nanking.
War makes for very bad choices. The decision by one nation to kill the citizens or representatives of another country would be totally reprehensible in most circumstances other than war. War itself is a cause of moral discomfort even among people who conclude that at least some wars can be morally justified. It is not my purpose here to discuss the justification of war, but to point to the fact that war is at best a moral gray area, and virtually any act of war is morally unjustified by an absolute standard of right and wrong, yet war is a moral reality, and our theory of morality must accept this fact.
An act of war, no matter how horrible, may be justified, if all of the alternatives are worse. The Nanking massacre was clearly a war crime, because the Japanese had better alternatives. The moral issue for Hiroshima and Nagasaki then is the issue of better alternatives.
The justfication argument was that the Hiroshima bombing, no matter how terrible and deadly it was, saved both Japanese and American lives. The argument against was that the Japanese would have surrended anyway, even if the bombing had not taked place. However, at the time when the Hiroshima Bomb was dropped, the Japanese were attempting to negotiate surrender turms with the United States. The United States had rejected Japanese surrender terms, and the Japanese appearred to be unwilling accept American surrender conditions. American conditiions rested on the beliefe that Japanese political institutions were a fundamental cause of the war, and long term peace between the two countries was only possible if Japanese political institutions were reformed. The Japanese unwillingness to surrender was based on an unwillingness by the Japanese power elite to accept the American mandated reformulation of their political institutions.
From the Viewpoint of the American Government, the Bombing was justified as a means of bringing home to the Japanese political elite that the nation faced distruction if it refused American Surrender terms. Three events influanced the choice by Emporor Hirohito to mandate that his government surrender, and to address the Japanese people on the necessity of surrender. They were the Hiroshima and Nagasaki bombings, and the Russian entry into the war, which occured on August 9, 1945, the same day as the Nagasaki Bombing. From this perspective, the use of the Atomic Bomb in Hiroshima and Nagasaki appears to have been justified.
(I intend to follow up this post with a discussion of how the Atomic Bomb has influanced perceptions of energy choices.)