How was the destruction different than if conventional weapons were used? How is an atomic bomb different than a conventional bomb? Please try to look at this through the eyes of someone making the decision in 1945, not through today's somewhat colored point of view.
I'm too young to have known a world without atomic weapons, but I'll offer a few musings anyway.
Although there are physical differences between the effects of the Hiroshima/Nakasagi bombs and what massive conventional bombing raids would have done (for example, the blast would be centred in a single place, caused local temperatures far higher than even those in the Dresden firestorms etc. and - of course - released significant amounts of radiation), I feel the key differences were political and psychological.
Prior to 1945 I suspect only the political, scientific and military elite of the major powers would have had any idea that atomic bombs were possible even as a concept, let alone as a practical device. The vast majority of the population would have had no idea of the devastation that could be unleashed - and I would venture the opinion that even those who did know of the concept of atomic bombs couldn't truly comprehend what they could do until they were used. Even small bombs such as those used (around 15 and 20
Kilotons IIRC - not even in the multi-Megaton range of subsequent years) caused terrible destruction and death.
I may be wrong but I've always felt there were two compelling reasons or goals for dropping the bombs on Hiroshima and Nagasaki.
- To force Japanese surrender without US forces having to invade the main islands
- To send an unmistakable message to Stalin that the USSR should not consider using military force to advance into Western Europe or Turkey and the Middle East
Apart from the obvious reason of saving the lives of potentially huge numbers of US servicemen, you could argue that the first goal also had a humanitarian element. During the invasion of Saipan many thousands of Japanese civilians killed themselves because they had been told the Americans would do terrible things to them. Many thousands more died as 'ordinary' casualties of war. The story on Okinawa was similar. The cost to the Japanese civilian population of an invasion of the home islands would almost certainly have been far, far worse than the effects of the two A-bombs.
Ultimately though my feeling is that those making the decision, which at the end of the day came down to Truman, had to use the atomic bomb. Changing the reality of warfare was the only way to make the Japanese military surrender and by doing that the lives of untold numbers of Americans and Japanese were saved. For this reason I have never believed the dropping of the atomic bombs on Hiroshima and Nagasaki should be regarded as a war crime (as many argue) or, as we are talking about here, an act of terrorism.
Sorry if that all seems a bit rambling, but as berberry has observed, this is an exceedingly complicated question.
Confused ? You will be...
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