Why did the US drop the second atomic bomb?

I’ve been wondering about the second a-bomb on Nagasaki and why it was deployed only three days after the Hiroshima bomb. I guess the most common explanation is that the Japanese cabinet did not surrender after the first bomb, but weren’t three days an awfully short time for the US government to come to such a conclusion, especially since they most probably knew about the very destructive nature of the a-bomb. According to what I’ve read, the Japanese emperor and some of the “doves” in the cabinet wanted peace even before the first a-bomb was dropped and it may have been a matter of time before they were able to break the deadlock that existed between the proponents and the opponents of surrendering.

Was there a good reason to not wait some time to inform the Japanese cabinet about the second bomb and see if they were definately not going to surrender? It just seems to me that the US government had very little regard for human life at that time.

Since I don’t know very much about this subject, can someone enlighten me?

I read about this not too long ago, I’m sorry I don’t remember where.

The point was to make it clear that we didn’t have just one bomb. It was thought that if we only deployed one, the Japanese might think we had just barely been able to make the one, and had done all the damage we could do. By deploying two, we demonstrated that we had the capacity to make multiple a-bombs, and put them in the position of having to wonder how many more might come.

It was a thoroughly thought-out and discussed strategy, and the conclusion of those involved was that it was psychologically necessary to drop two bombs.

It just seems to me that the US government had very little regard for human life at that time.

From what I’ve read in various places, military historians and strategists pretty well agree that if we had not dropped the a-bombs, the Japanese would have fought to the last man defending an invasion of Japan (which would definitely have been launched, and which was mere days away from happening). The loss of life from this invasion would have been hugely more than the loss of life from the a-bombs. So strange as it may seem at first thought, using those bombs saved a great many lives, both Japanese and American, compared to the alternative.

How is demonstrating to Japan the capacity for more than one bomb psychological? Or am I missing something?

Were more than two bombs intended for Japan?

I was interested to read here, in a purported written order from the time:

Clearly dropping a nuke on a civilian population takes more than a little thinking through, even soul searching. The discussion on its justification is hotly debated, perhaps even GD territory. I happen to agree with Gary’s analysis. The second bomb couldn’t have sent a louder message that we wanted this war over and we weren’t effing around.

We’ll never know if it was absolutely necessary, but it certainly did the trick.

Until someone more qualified comes along, I’ll throw this out there. Theories I’ve heard in one place or another (no cites)

~ It was to prove to the Japanese that we didn’t have just one bomb at our disposal.

~ It was to prove to the Russians that we had more than one bomb at our disposal.

~ It was feared that the Russians, having recently declared war on Japan, would eventually take them, too. The Japanese were going to be defeated by the US at any cost (Emotional response stemming from Pearl harbor) We didn’t want the Russians to any more influence in the world than they already had in Europe.

~ It was genuinely believed that the Japanese would not surrender, and force us to take the nation by hand. The Japanese were not known for their propensity to surrender. We had to be as convincing as possible.

Well, neither did the British, Germans and Japanese. The terror bombings were just the way that war evolved for various reasons. (It started in error, as I understand it) Those atom bombs just turned a day long job into a single mission job. (To them. Fallout wasn’t really well understood at the time) We did worse city bombings in Japan and Europe with conventional weapons. Had the Japanese and the Germans found themselves with the means, they’d have done it to us as well.

I’ve heard it proposed that the Japanese didn’t surrender because of those bombs alone. One theory goes, that with Russia declaring war on them, they figured they couldn’t fight both of us, so they gave it up to us. A wise choice, given the other possibility.

There has been a great deal of controversy regarding the second bomb, and many, with the great perspective of hindsight, are questioning the ethics of that second nuclear strike. The obvious reason is, as said, to force Japanese surrender. The regime in Tokyo seemed to vacillate even upon the demonstration of force at Hiroshima, thus the second strike.

Of course, there’s theories that explore the motive. Sources differ on this. A lot of them quite biased. I don’t have convenient cites for these, but a Google search for +“Nagasaki” +“second bomb” +“why” would net you a whole list of books, analyses, and dubious opinions. Some sources indicate that Truman wanted immediate and unconditional surrender before Soviet forces intervened. The Soviet declaration of war caused something of a stir, and the US wanted unchallenged influence over post-war Japan for security reasons.

Another theory explain that the second bomb was to reinforce the perception that the US has unlimited numbers of nuclear weapons (when in truth, it has more or less expended its nuclear arsenal) and could utterly decimate Japan without deploying an invasion force. Sort of a psychological thing. Alternatively, some indicate that the second bomb is a gesture/warning to the Soviets in the same fashion.

Finally, there’s a somewhat dubious theory that Japan had attempted to test their own, single nuclear device off Korean shores and assumed the U.S. had only one as well. That was a new one to me…but this book explored it quite in detail.

Jury’s still out on this whole Nagaski issue, though, I think.

From my first post: It was thought that if we only deployed one, the Japanese might think we had just barely been able to make the one, and had done all the damage we could do.

If we had only dropped one bomb, it’s very likely that the Japanese would have figured we had spent our load and they had no need to worry about our doing it again for quite a long time. Then they would have wanted to fight on, with vigor. Dropping the second bomb made that line of thought insupportable.

How’s this for an analogy:
Imagine that you are in a gunfight in the Old West; both you and your opponent have six-shot revolvers. If they fire six shots, then stop and tell you to give up then you could assume that they emptied their gun and are bluffing. If they fire seven shots, then they obviously have more than one gun and can probably continue shooting.

Along with the U.S., both Germany and Japan had atomic bomb programs during WWII, but the Axis powers had not been able to develop a bomb. The Japanese might have assumed that, even if the U.S. knew how, the actual manufacturing of a bomb was a million to one shot.

David McCullough states in his biography of Harry Truman that they had more bombs in the pipeline for use in Japan. After the second bomb was dropped, Truman signed the order which stated that no more bombs could be used without his authorization for each and every case.

Truman was a combat veteran (he served in WWI and BS’ed his way through the medical exam in order to serve) and clearly stated that his goal in using the bombs was to shorten the war. The Japanese had been talking about a conditional surrender for some time before the bombs were dropped. However, when you look at the atrocities committed by the Japanese (The Rape of Nanking for one), it becomes obvious that there was simply no way the Allies ever would have accepted a conditional surrender from Japan.

Remember, at the time the bomb was used, we had very little idea of what they could do. Sure, we knew it was the most powerful weapon ever developed, but radiation and its effects on people was still only barely understood. It took the bombings for us to know the horror that was unleashed. Even then, we still didn’t fully understand it.

The simple fact of the matter is that the people who made the decision were acting upon the best information they had available at the time. They made the choice to use the bombs based on that information, and Harry “The Buck Stops Here” Truman maintained until his dying day that he’d never do it any different. And anyone who’s read about Harry Truman, would never call Truman a bloodthirsty tyrant. Indeed, the reason he gave for pulling the authority from the military to use the atomic bombs was, “Because I can’t stand the thought of all those kids being killed.”

Okay, I understand how it works, but I guess I was misinterpreting the word “psychological”. I was thinking the point of psychological-type warfare was to psych your opponent out, make them scared, and generally have them succumb to propoganda. This reasonable, bullets-counting thing was not what I had in mind. But I get it now. :slight_smile:

Could the fact that the 2nd one was far more powerful then the 1st have anything to do with it? ‘Sort of, hey wait a second, we got an new an improved version, try this one out before you decide’.

…I guess I was misinterpreting the word “psychological”. I was thinking the point of psychological-type warfare was to psych your opponent out, make them scared…

I wasn’t referring to psychological warfare, but to the psychological effect of this particular strategy. Nevertheless, to some extent it probably did psych them out and scare them.

My natural human inclination is to look at the second bomb as an atrocity, alongside Dresden, and the Blitz. But my emotions 50 years after the fact are just my opinion, and I’m not Vulcan, so opinion is opinion, and putting aside emotion. It ended the war sooner rather than later.

Do a Google on “The Rape on Nanking” and you’ll get an idea of the enemy we were fighting those decades ago. After what they did to Pearl Harbor they shouldn’t have expected mercy.

Here’s another Google for you
“Bataan Death March”

I guess that if I have a point it is that Nipon reaped what it sowed, and yes it was all horrible.

AP
It’d be interesting to see how the Japanese press handled the Hiroshima bombing in the few days before Nagasaki. Tokyo had been getting pasted pretty hard with an incendiary campaign, and it’s possible that the Hiroshima news simply got buried in stories of more pressing local disasters. Atomic bombs weren’t exactly part of the man on the streets worldview back then.

Insofar as there’s a GQ answer to the question, it’s the document Ice Wolf linked to. Spaatz, as commander of the SAC, wanted the order on paper from Handy, the Acting Army Chief of Staff. There appears to have been some communication back and forth between Handy in Washington and more senior figures in Potsdam. There’s no direct evidence that Truman saw the order in draft, though many have made the inference that it must surely have been shown to him. The only signature on the order is Handy’s (it’s reproduced on p55 of Judgement at the Smithsonian, ed. by Philip Nobile, Marlowe, 1995. Given the controversy there, I suppose I should say that I find Nobile’s intro silly, the Smithsonian script more or less okay and Bernstein’s afterword interesting.) It’s pretty plain that Handy’s order devolved authority for the targeting, number and timing to the field commanders and it was taken this way by Spaatz and Groves. After Hiroshima, they regarded this as authorisation to bomb a second target (which turned out to be Nagasaki) and they were presuming that they’d use the third bomb on the same basis once it reached Tinian.
Where the issue drifts off into GD territory is the rational for framing the order this way. There isn’t much contemporary information about this stage of the decision making and much post facto memoirising. Personally, I don’t think some of these issues will ever be resolved.
As further evidence that this is a GD issue, there were those involved in the process, at least indirectly, who came to think that while Hiroshima was justifiable, Nagasaki was not (Peierls, Teller, Weisskopf, etc.). Situations where people change their mind in hindsight are inevitably controversial, since you can appeal to both what was known at the time and known later. Add in those who didn’t change their mind about the second bombing and it’s a mess. One’s judgement on the issue will depend on what standard you want to apply and that will be value laden.

I have seen it suggested (though I don’t know where and am not convinced) that the second bombing came as a surprise to Truman. Rhodes’ account (The Making of the Atomic Bomb, Simon and Schuster, 1986, p743) has Stimson arguing on August 10th for a halt to all bombing, but Truman refusing. The compromise that afternoon was halting atomic bombing.

Besides all of the excellent explanations given above, there is another reason that Nagasaki was targeted.

It was home to the Mitsubishi torpedo works. The same torpedos that sank so many of our ships at Pearl Harbor.

The main reasons still stand.

The use of atomic weapons saved as many, if not more Japanese lives than they took. Had it been necessary to instigate a land invasion of Japan, there would have been massive loss of life on both sides. After all of the Japanese atrocities, there was little patience for such a potentially prolonged and drawn out conflict.

The Japanese were a tenacious enemy. Surrender was not in their vocabulary. Google Okinawa or Iwo Jima to find out more. It was necessary to demonstrate not only a credible threat but one of absolutely devastating power to bend their will to defeat.

Japan, being a highly productive industrial society, required an incontrovertible demonstration that the United States had the capacity to continue producing (and using) atomic weapons in unlimited quantities.

It is also pretty likely that a nation which revered ritual suicide as an honorable practice had to be faced with nothing short of horrific and total obliteration in order to force its hand. This was done and both the USA and Japan are the better off for it.

Not likely… bomb design was so primitive in those days that they probably weren’t exactly sure how big of a bang that Little Boy would make(untested design).

The important thing, like others have said was that we give the impression of being able to obliterate the Japanese cities at will with these new weapons. Truman’s “rain of ruin” would hardly have been very convincing if we only destroyed one city.

Basically we were putting our money where our mouth was.

Even after the 2nd bomb was dropped, there was no guarantee of Japan’s surrender, even after the Emporer himself came forward and said that Japan would surrender. There were very high ranking military officers, including Tojo, who were plotting and planning a coup/assasinating the Emporer, after which the fight would have continued. Fortunately, some lower ranking officers didn’t follow along with their superiors.

Also, it would have taken the US at least 2 months to produce another bomb.

And while it may have been used to try and shock the Russians, Stalin had known about the Manhattan Project from about mid 1944 onwards, in fact, when Truman told him about it at the Potsdam Conference, Truman was surprised at how nonplussed Stalin was upon hearing the news, Truman not knowing that Stalin already knew about the Manhattan Project.