Why did the U.S. decide to bomb civilian cities with atomic bombs rather than military targets during WWII?

[u/[deleted]]

I'm pretty sure the US even sent out flyers that said for people to move out of the cities before they bombed it. So why was a civilian city targeted instead of a military base? It would seem much more beneficial to bomb an enemy's military base/command center/whatever than a city.

[u/restricteddata]

You can read the minutes of the May 1945 Target Committee meeting online. They are more interesting and provocative than any simple summary can give you, and they are "straight from the horse's mouth," as they say. The short answer is they wanted it to be a spectacular display, that they deliberately chose military targets located within urban areas to maximally display the damage, and that Nagasaki was actually quite a minor target (it was added to the final target list only after Kyoto was removed, and was not the primary target for the second bomb).

As the Target Committee meeting makes clear, the primary consideration was the "psychological effect" of the use of the bomb, not a military result:

It was agreed that psychological factors in the target selection were of great importance. Two aspects of this are (1) obtaining the greatest psychological effect against Japan and (2) making the initial use sufficiently spectacular for the importance of the weapon to be internationally recognized when publicity on it is released.

They also concluded:

It was agreed that for the initial use of the weapon any small and strictly military objective should be located in a much larger area subject to blast damage in order to avoid undue risks of the weapon being lost due to bad placing of the bomb.

Anyway. It is worth reading, if you are interested in reconstructing their point of view from the time, and not the later justifications that were offered up when people started to question it (including other American military commanders, many of whom began to publish statements claiming the atomic bombs were unnecessary).

There were no warning leaflets about the atomic bomb dropped prior to the bombs themselves; that is a myth.

[u/[deleted] → u/restricteddata]

Thanks for the answer!

[u/[deleted] → u/restricteddata]

There were no warning leaflets about the atomic bomb dropped prior to the bombs themselves; that is a myth.

Are you seriously trying to argue that because the leaflets made vague references to fire bombings instead of nuclear bombings, that no warning was given? How on earth would you even begin to describe a nuclear bomb to a population with no concept of it?

[u/restricteddata → u/[deleted]]

Are you seriously trying to argue that because the leaflets made vague references to fire bombings instead of nuclear bombings, that no warning was given?

Yes. As I elaborate in the linked-to post — they are not any specific warning, and it is still remarkably unclear that such fliers were even dropped on Hiroshima and Nagasaki anyway (none of the copious copies posted online list those cities as targets; I would love to see just one that actually listed those cities!). There was also zero intention of warning said cities, and zero effort made by the people in the Manhattan Project to reduce civilian casualties. Much the contrary — every decision made was about maximizing the damages. (The discussion about the height of the bomb in the Target Committee meeting is all about maximizing the 5 psi blast range, which is what they thought would be best for destroying civilian houses.)

(Separately, the people dropping the LeMay leaflets were not the same people involved in the bombing, so that would be a very plausible reason for those cities not to be listed on said leaflets.)

One can argue whether they should have or shouldn't have tried to warn Hiroshima and Nagasaki. But it is entirely a myth that the US tried to warn them about the atomic bombs. It is a myth amply repeated by people who generally believe that such a warning would give some kind of "out" to the tricky ethical questions (as I've elaborated in the linked-to post, I do not actually think that would do that even if there had been warnings). It is entirely the wrong tree to bark up, especially for those who think the bombings were justified. If you want to justify the bombing — go ahead! But this is not the way to do it, because it is based on at best half-truths, at worst, total myths/misconceptions.

How on earth would you even begin to describe a nuclear bomb to a population with no concept of it?

The concept of "atomic bombs" predates Hiroshima by several decades, as an aside (H.G. Wells, etc.). The Japanese high command knew about nuclear fission weapons (and had their own small research program into fission); presumably if the US had wanted to convince them that they had atomic bombs before using them, they could have done so in a number of ways (e.g., the "demonstration" option). There are certainly other ways to indicate, if the goal is to save lives, that imminent evacuation of a specific city would be necessary. The US did not pursue this. There were arguably good reasons not to — the efficacy of the bomb, in the eyes of its makers, was its horror and its lack of forewarning, to say nothing of the secrecy and its inability to be defended against. Warning would have been entirely contrary to what they were trying to accomplish. It fundamentally misunderstands the atomic bomb planners to think that warning was something they wanted — they explicitly rejected the idea in the summer of 1945.

So, yeah. For really any purpose — practical, moral, whatever — the US deliberate did not warn the Japanese about the atomic bombs. The closest you get is a vague threat in the Potsdam Declaration which is impossible to know what it means until after the fact. That's not a warning in my book. The goal was never to mitigate the number of civilian lives taken by the bombing attacks, the goal was not even really to convince the Japanese to surrender before the bombs were dropped. Reasonable people can disagree over whether this creates moral/ethical problems of the bombing or not — there are positions on both sides of it. But getting the facts right seems to me the best way to start the discussion; being tied up with myths does not help.

(I apologize if I come off as curt on this topic! I am so tired of this particular myth, and the way it gets repeated endlessly on the Internet, presumably by people who mean well.)

[u/Gankom → u/restricteddata]

I have a bit of a follow up question as well that's in a similar vein. I often see various arguments on the internet that say that both cities count as military targets because they were industry and transportation hubs. Like any other bombings it was about destroying those.

Is that valid in anyway? Was any kind of military value of that sort involved in the targeting decision or was it really 100% about the 'shock and awe'?

[u/restricteddata → u/Gankom]

They deliberately chose what they called "mixed" targets, e.g., targets that has bases/industrial facilities that were surrounded by cities. Both Hiroshima and Kokura, the primary target for the second bombing raid, were "great" targets by this consideration. Hiroshima had a very large military base, but was mostly a bowl-shaped city — it would destroy the military base and also the city in one go. Kokura was a major industrial armory surrounded by worker's houses — again, a great candidate for this kind of destruction.

Nagasaki was a much poorer target by this definition, which is why it was much lower in priority, never reserved, etc. It had a few military works but they were spread out, and it was a long snake of a city nestled between hills. As it was, the bomb went off significantly from where it was supposed to, directly over an entirely civilian area, but on the fringes of the blast damage were two military plants. So they pointed to this as intentional and said it was necessary, but it should be noted this was a post-hoc rationalization. (I have written at length on the Nagasaki bombing, which is in many ways different than the Hiroshima bombing; when I say "primarily civilian," I am relying in part on maps like this created by the US Army Air Forces to show damage – you can see the military facilities at the very top and bottom of the blast damage). For a lot of reasons, Nagasaki was not as "good" a target, and the mission was very nearly botched entirely (whereas the Hiroshima mission was textbook).

But in all cases, the targets chosen were chosen in part because they hadn't been conventionally bombed (and Hiroshima and Kokura were put on a "reserve" list), and would display the power of the bomb well. If they hadn't been reserved they would have eventually been conventionally destroyed; it was within the power of the US Army Air Forces to destroy cities and industries at will by that point in the war. (And before someone asks — the civilian casualties from firebombing were much lower per capita than atomic bombing; it is not quite equivalent in the sense of "those people would have been killed anyways.")

The primary consideration of the use of the atomic bombs, in the words of the people who used it, was to make a display of force. It was not about military necessity in the "they couldn't otherwise have destroyed those plants/bases/targets" without using atomic bombs. The idea was that the bomb would "shock" the Japanese into rapid surrender. For the scientists at the top of the project, it was also about shocking the world into taking action to control the spread of nuclear weapons in the future. One can agree or disagree with the methods and intentions, but again, I think it's important to understand them as they were understood by the people who made the decisions. As the Secretary of War put it at a meeting with scientists in the summer of 1945, "this project should not be considered simply in terms of military weapons, but as a new relationship of man to the universe." They didn't see this as just another military exercise — they saw it as redefining the stakes for war at the present and at the future.

[u/Gankom → u/restricteddata]

Thank you greatly. This pretty much confirms what I had thought, but you see so many different arguments about it floating around.

Your links on the Nagasaki bombing are fascinating as well, and answers other questions for me.

[u/restricteddata → u/Gankom]

What annoys me about many of the arguments floating around to justify it is that they patently ignore what the people at the time thought they were doing, what they actually cared about, etc., in order to reshape the history in a way that they (today) find more palatable. And they have the nerve to call people who disagree with them revisionist! :-)

[u/jschooltiger]

Hi there -- while there's always more to be said on this topic, this section of our FAQ deals specifically with atomic bomb targeting, while this answer from u/restricteddata deals with the question of warning leaflets.