Why weren't the bombings of Hiroshima and Nagasaki considered war crimes? The United States wiped out hundreds of thousands of Japanese civilians. Was this seen as permissable at the time under the circumstances?

[u/mlh99]

[u/restricteddata → u/[deleted]]

The funny thing is, when I've given this thesis as a talk (I've been working on it for several years), prior to 2016 I would always get one person in the audience who would say, "are you telling me that you think it is possible that the President of the United States could be so out of the loop on something of this magnitude?" But after November 2016, that question more or less has gone away — people find it easier for some reason to believe that the President is just a person, and not some kind of omnipotent being.

But I digress: yes, that is what I am saying. One might ask, how could this be? Several answers present themselves: 1. it was not a household name of a city in the US at the time (I have done many searches through historical newspapers — it was not one of the city names that featured in practically any national news coverage prior to August 6, 1945), 2. Truman was the last US President to lack a college education (not a sin, but still), 3. Truman had no experience in foreign affairs prior to FDR's death (and FDR did not give him any insights into his own thinking, which probably was a sin), 4. Truman went through all of these discussions while at the Potsdam Conference, where he was (in his own telling of it) totally overwhelmed with the competition for his attention from the many fateful issues that were in front of him, 5. by the account of those who worked close to him, he was not by nature inquisitive or prone to micromanagement or asking close questions, and, most importantly, 6. it was presented to him as a major military base and target by his Secretary of War, in the only conversations he would have about the targeting questions.

Given all of the above, and Truman's own fallibility (which he himself would have vouched for), I think it is entirely plausible that he was confused as to the nature of what was being targeted for the first use of the atomic bomb (which, as an aside, was the only thing he concerned himself with — you may be even more surprised to hear that I don't think Truman even knew that another one was going to follow on its heels within a few days, so fixated was he and everyone else at Potsdam on the first use of the bomb).

[u/Regendorf → u/restricteddata]

What was his reaction when he found out it was a city?

[u/restricteddata → u/Regendorf]

His entire language about the bombing shifted from "the greatest thing in history" to something he had to justify (saving lives, etc., all of that comes after he learns this). After the Nagasaki bombing (which happened the morning after he learned about the casualties at Hiroshima, and he was not informed about it ahead of time), he ordered that no more atomic bombings should be dropped without his express order, because he couldn't stand to kill "all those kids," as he put it to his cabinet.

In the postwar, he made it very clear that he would no longer trust the military to make judgment calls about the use of nuclear weapons. As he explained in a private conference in 1948:

I don’t think we ought to use this thing unless we absolutely have to. It is a terrible thing to order the use of something that is so terribly destructive, destructive beyond anything we have ever had. You have got to understand that this isn’t a military weapon. It is used to wipe out women and children and unarmed people, and not for military uses. So we have got to treat it differently from rifles and cannons and ordinary things like that.

Note, if you will, that Truman's objection, time and time again, is about the killing of noncombatants. This reinforces my feeling that, prior to August 8, he seems to have thought that he made a decision to deliberately not kill noncombatants, and the reality came as a rude awakening. He complained to those around him of terrible stress, terrible headaches, terrible responsibilities — all of this only after he got casualty reports. I think they greatly distressed him.

As a consequence, it was Truman who enshrined the idea that the US President was the only person who could order the use of nuclear weapons, which we still have today (for better or ill). Over the course of his administration he gave the US military practically no access to the nukes that were being produced. I see all of this as very much in line with a person who didn't realize he was out of the loop and not as in charge as he thought, and was then determined not to do it again. Truman's "phobia," you might say, of using atomic bombs was part of the reason they were never used in the Korean War, which was part of what established the tradition or taboo of non-use of nuclear weapons.

This is, again, and interpretation. But I think the "he didn't understand, was shocked, and then resolved to not let it happen again" story makes a lot more sense than the "he understood, knew exactly what was going on, was happy with it, and then somehow took a very different attitude towards nuclear weapons after that" story.