r/HistoryWhatIf • u/The-Protractor-Cult • 1d ago
What if the US warned and demonstrated the nuclear bomb on uninhabited land before Hiroshima?
What I mean is what if the US government warned the Japanese by saying they have such a weapon, and will drop it on an uninhabited island off the coast or on the water, pre-warning and allowing the Japanese to send officials to see it, while not killing anyone?
Then issue an ultimatum that by a certain amount of days if they do not surrender, then they will use another on an actual target.
Was this feasible to begin with?
I should say I do understand that many officers and officials didn't believe the Hiroshima attack was real or thought it was exaggerated, and that ultimately no action was taken when people (mainly civilians) were killed, but I understand that to be not believing the US had a second bomb? Would a demonstration prove that they may as Japanese officials believe they wouldn't waste on a non-target?
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u/colt707 1d ago
So few things. It was unknown if it would actually work. They were pretty sure it would work because it theory it worked but the first bomb dropped on Japan was really the finally test. Drop it as a test to demonstrate it to the Japanese its power and the bomb fails to detonate? That’s going to make surrender far less likely. The other thing is where are you going to drop it? Over the ocean is going to be a very lackluster display because the bomb going off is impressive but the destruction is what is mind boggling. So you’d have to drop it on either an ally that Japan has pushed the borders of its empire up to or on land that Japan has claimed as its own. If Japan agreed to this then they’d clear out their soldiers and leave any native civilians to be blown away. A strike on say Chinese land wouldn’t have the impact that a strike on Japan does because it allows for them to say “well you still have to get to Japan.”
The US wanted an unconditional surrender, which the surrender agreement that was reached was basically unconditional. There were a few things that in the grand scheme of the war were incredibly minor. But Japan had been in peace talks with the US for months before they surrendered. The original surrender agreement offered by Japan was basically the war is over and everyone keeps the land they’ve taken and we’re all good. A majority of the Japanese high command didn’t believe the reports from the first bombing and were arguing against surrendering unconditional. It between the bombings they captured an American fighter pilot and interrogated him about the bombs, obviously he had no idea but bullshitted his way into saving his own life. By the time he was transported to mainland Japan and interrogated by the Japanese scientists working on their own nuclear project who figured out he was lying, the second bomb had been dropped. That was what convinced the emperor of Japan that the Americans couldn’t be beaten. As for the scientists who worked on Japan’s nuclear weapons project, the one thing they believed that the fighter pilot told them was that America had dozens of those bombs, which makes sense because to a scientist if you can do it once then you can probably do it twice and if you can do it twice then you can do it an indefinite amount of times.
Lastly we have to remember what Japanese culture was at the time. Fighting age males had been raised on a romanticized and bastardized version of bushido. These were men that were raised to be warriors by a twisted version of a warrior culture in a time of peace. There was nothing greater you could achieve than killing and dying for your country and your emperor to many of them. To many of them there was nobody that was even on par with the Japanese on any level, that changed as the war dragged on but it was still prevalent in the final stages of the war. These were soldiers that came from a culture where humans didn’t surrender, humans fought to the death. You see this attitude in how they treated captured soldiers that surrendered vs captured soldiers that were unconscious when captured because the latter never actually surrendered. Japan was willing to fight until the very bitter end, be that defending the mainland to the last person or be it bombs being dropped that cause damage that is nothing but a conceptual theory to the rest of the world.
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u/EasterShoreRed 1d ago
All good points! So I won’t try to say it better! I’ve also seen reports that there were concerns Japan might move a bunch of POWs to where ever a bomb would be dropped if there was a warning and we didn’t want to end up killing a bunch of American and British soldiers.
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u/ijuinkun 4h ago
I would add that they were willing to die defending their homeland as long as they could take the invaders to Hell with them. The nuclear bombs made this no longer possible—the enemy could now kill an entire city while risking only a single flight of airplanes, which effectively meant that their deaths would gain nothing for the Emperor.
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u/AllswellinEndwell 1d ago
This is a good assessment. Two things I'll add. One, the US has wiped out cities to a greater extent with fire bombing and conventional tactics and in the US commands eyes it didn't appear to phase them (as you said the Japanese were extra)
Second, the thing the Japanese feared/loathed the most was communism. The Soviets were blasting through Manchuria just days after the first bomb. They knew their position was untenable and would rather deal with American occupation than face Soviet occupation.
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u/AlexRyang 1d ago
Japan only surrendered after the USSR launched a massive invasion into Manchuria and destroyed the last two significant Japanese field armies. There are records in Japan that they had no intention of surrendering after the two nuclear weapons.
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u/rhino369 1d ago
This is wrong. The reason the Soviet invasion was a shock isn’t because the Japanese lost an army. That army was essentially stranded in Manchuria and couldn’t be moved to fight America in their home island. It was useless. And it wasn’t even combat ready. It was an occupation force mostly with outdated weapons.
The shock was that the Japanese thought could use the Soviets to get a better peace deal. The idea the Japanese were more afraid of them than the US that was already invading their home islands and who already killed millions of their civilians is preposterous.
There is a ton of evidence the nuclear bombs played a huge role. A decent amount of the war cabinet wanted to after the first bombs. Though they would have eventually surrendered anyway. The US conventional bombing wasn’t that much less devastating.
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u/StonkyDonks069 1d ago
This is an excellent reply. The one thing I'd add is that the nuclear bombs gave a face-saving way out for the regime. Despite this, there was still an attempted coup that aimed to keep the war going.
So, to your point, the Soviet invasion itself was insufficient, especially as the Soviets could not invade the Home Islands. The nukes were the impetus for capitulation, and the Soviet declaration hastened the process.
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u/FerdinandTheGiant 1d ago
The Soviets could invade the Home Islands (Hokkaido) but even if they couldn’t, Japan didn’t know that.
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u/TheAsianDegrader 1d ago
The Soviets could only invade with the help of the American Navy. The USSR had no navy to speak of at that time.
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u/FerdinandTheGiant 1d ago
They likely would’ve successfully landed at Rumoi on Hokkaido because it was totally undefended.
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u/Grouchy-Big-229 1d ago
Definitely not after Hiroshima because the military was just treating it as another bombing. Tokyo had sustained more damage and death from bombing than Hiroshima. It was Stalin that freaked out and launched the Manchuria attack that led to the eventual surrender. Stalin wanted to be part of the negotiations so they had to have skin in the game, so they attacked as quickly as they could. The Japanese were more afraid of the Soviets. They had history. Hirohito’s broadcast to the nation just after Nagasaki was more about the Soviets than the bombs.
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u/Reasonable_Pay4096 22h ago
Stalin didn't freak out. At Yalta, he agreed to declare war on Japan 3 months after Germany surrendered. Germany surrendered on May 8th & the USSR declared war on August 8th, between the two bombings.
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u/Difficult-Jello2534 1d ago
That's not true. They actually were close to surrendering before the bombs were even dropped. In fact , mistranslation was a big part of that, its often called the "saddest mistranslation in history" .
The real reason that nobody wants to accept as to why we dropped the bomb is that we could NOT risk USSR conquering Japan first, especially with how the western theater went. The second was we spent more on the bomb than the war, and we were going to prove to the world we were the most powerful.
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u/Puzzleheaded_Way9468 17h ago
I think there's another whatif to be had here. What if Japan calls the US on their bluff, and doesn't surrender? Either because of different bombing circumstances, or because the emperor is just ready to play chicken.
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u/hedcannon 1d ago edited 22h ago
I doubt it would have worked (even if possible). After using TWO bombs on Japan proper there was still an attempted coup to prevent surrender.
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u/BathFullOfDucks 1d ago
The allied powers did warn Japan in the Potsdam declaration The might that now converges on Japan is immeasurably greater than that which, when applied to the resisting Nazis, necessarily laid waste to the lands, the industry and the method of life of the whole German people. The full application of our military power, backed by our resolve, will mean the inevitable and complete destruction of the Japanese armed forces and just as inevitably the utter devastation of the Japanese homeland.
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1d ago edited 1d ago
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u/rhino369 1d ago
The Japanese had not already surrendered.
There is likely some truth that they would have surrendered earlier if the USA offered a surrender that explicitly allows the emperor to stay.
But the Japanese never even tried to negotiate better terms than the postdamn declaration. At least not with America.
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u/Baguette72 1d ago
Japan had not surrendered. Not by any definition. It was sending out feelers to try and get a meeting where they could negotiate a peace deal, not even a surrender a negotiated settlement.
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u/Low_Stress_9180 1d ago
Would have been taken as a sign of weakness and strengthened Japanese resolve. A silly idea.
Japanese scientists thought IlUSA could only make one bomb a year with Uranium - they didn't know about Plutonium bombs.
It took two in quick succession to shock them.
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u/Smooth-Reason-6616 1d ago
The full Japanese cabinet met at 14:30 on 9 August, and spent most of the day debating surrender. As the Big Six had done, the cabinet split, with neither Tōgō's position nor Anami's attracting a majority.
Anami told the other cabinet ministers that under torture a captured American P-51 Mustang fighter pilot, Marcus McDilda, had told his interrogators that the United States possessed a stockpile of 100 atom bombs and that Tokyo and Kyoto would be destroyed "in the next few days"..
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u/Shimmy_4_Times 12h ago
Would have been taken as a sign of weakness
This is important. If the US was afraid to bomb military targets, out of respect for human life, successful Japanese resistance becomes more plausible.
Maybe the US could have selected a military target with fewer civilian casualties than Nagasaki/Hiroshima, but that still wouldn't be the "uninhabited land" OP is talking about.
Also, this isn't the subject of this post, but part of the Japanese motive for surrender was the declaration of war by the Soviet Union. Japanese aristocrats didn't want to be conquered by the US, but they REALLY didn't want to be conquered by the Soviets.
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u/pinesolthrowaway 1d ago
Wouldn’t have made a difference. Nuking Hiroshima alone made no difference
It was only after Nagasaki that the Emperor personally got involved and broke a tie in his council on whether to end the war or not, and even then some hard liners in the military still tried to coup him and stop Japan from surrendering
Using a nuke on an open field isn’t going to make a difference if that was the reaction after dropping two on cities
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u/Deep_Belt8304 1d ago edited 1d ago
Maybe in a fictional world were the Japanese government were rational actors and not a suicidal death cult, but they were one.
So this wouldn't have done anything besides needlessly prolong the war.
They would just claim its propaganda designed to intimidate them and continue the war which is what they did after Hiroshima was bombed.
If it took two direct nukes to convince the Japanese Emperor to unconditionally surrender - the mere sight of one being detonated in a country 5000 miles away from Japan would not cause them to surrender, most Japanese cities were getting firebombed on a regular basis with many losses.
Actually if the US demonstrated the bomb the Japanese milirary would instruct them to resist harder as backing down would be a sign of weakness.
What Japan would do is go back to butchering tens of thousands of civilians daily which they were perfectly fine with doing so long as nobody dircectly opposed them on land.
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u/malumfectum 1d ago
If the Japanese government were rational actors, things would not have progressed to the point where the bomb was necessary.
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u/silent_b 1d ago
Japan should have surrendered well before the atomic bombings. They had plenty of evidence of overwhelming allied superiority even without the bombs. Whatever it took to get them to surrender as quickly as possible was the correct choice. That means real bombs on real cities.
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u/Grouchy-Big-229 1d ago
Should have? Maybe, but the military leaders wouldn’t allow it. They had amassed over a million soldiers and citizen soldiers on the south of Kyushu after the US took Okinawa, prepped to defend the homeland (the four major islands of Japan). The military was going to fight to the end.
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u/FerdinandTheGiant 1d ago
The plan for Kyushu wasn’t to fight until the end, it was to bleed the US to the point that they could get a negotiated surrender.
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u/Grouchy-Big-229 1d ago
Isn’t a negotiated surrender just another outcome? Another ending? They were either going to fight to the last man, woman, and child, or they were going to fight until the enemy wouldn’t fight anymore.
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u/adminscaneatachode 23h ago
A negotiated surrender is better than a unconditional surrender. They knew they had ‘lost’ the war when they failed at Pearl Harbor. The war goal was to neuter American presence in the pacific, not to invade the continental US, they didn’t want a drawn out war with America. Everything after that failure was to make the eventual allied invasions as painful as possible in the hopes of forcing a peace.
The war with America was a last ditch effort and a Hail Mary, it wasn’t their first or tenth choice. It was a gamble they’d taken, and ate shit on, and they knew it.
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u/FerdinandTheGiant 1d ago
It’s not likely they’d “fight to the last man, woman, and child”. There were definitely hardliners in the military who may have preferred such a thing, but it’s far from likely, largely because not every man, woman, and child would fight. Polling shows largely the Japanese population at the time had given up on the war effort and there were real concerns within Japan’s government about potential uprisings.
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u/matsonjack3 1d ago
Remember at this time and for the whole war Japan thinks their leader is a god. We even dropped notes on most cities(both nuke sights)(Dresden too) we were bombing that we knew had large civilian populations warning them of an attack. That could have been an empty city, if other people were in charge of Japan at the time.
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u/FerdinandTheGiant 1d ago
We didn’t drop pamphlets warning of potential nuclear strikes until after Hiroshima, not before.
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u/matsonjack3 1d ago
We did drop leaflets August 1st 5 days before to 33 different targets cities. Including radio messages before the 2nd strike directly to Nagasaki.
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u/FerdinandTheGiant 1d ago
We didn’t drop leaflets to any target city prior to the first strike. We can see the planners explicitly reject such a plan.
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u/matsonjack3 1d ago
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u/FerdinandTheGiant 1d ago
Mate, as they say, that’s the LeMay leaflet. That was made and used for the firebombing campaign. Hence why there is the appearance of a plane dropping firebombs. There is no evidence such a leaflet listed any target cities or that it was used to try and warn any target cities.
See my reply from this post for more info.
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u/matsonjack3 1d ago
So this information is only from Truman’s perspective, and although it’s good insight it’s still doesn’t change the fact that we did warn them. Pulled from my source - “Read this carefully as it may save your life or the life of a relative or friend. In the next few days, some or all of the cities named on the reverse side will be destroyed by American bombs.”
This exactly was dropped to 33 cities including both Hiroshima and Nagasaki. Also that leaflet message says bombs…. Not just fire bombing in particular.
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u/FerdinandTheGiant 1d ago
You need to scroll to see my second comment, not the one about Truman.
There is no evidence it was dropped on any target city. They were not included in the list of cities because again, these leaflets were for an independent campaign. I’ve already linked you to direct sources where the planners before and after the bomb discuss not giving a warning (again, scroll). It’s fairly cut and dry, we didn’t warn them.
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u/matsonjack3 1d ago
But yet there is evidence of us dropping 5 million of them. Believe what you want, but everywhere I look I find articles explaining exactly this. Even when the information is right in front of you are to blind to see it.
Stop looking at this w opinions and just read into facts. Your comment in the Truman post is again strictly from Truman’s perspective and not even about facts did we warn them or not. It’s a yes or no and evidence everywhere points to yes.
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u/FerdinandTheGiant 1d ago
Mate, you cited Quora. I’ve already linked the literally meetings, a link to a PhD Historians blog on the subject, and more statements made by the Secretary of War which all confirm what I’m saying and all of which has nothing to do with Truman.
Cope harder because it’s evident you have no desire to look at the facts of the matter. Though more realistically it seems like you’re struggling to figure out how to scroll and read the reply I actually linked.
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u/Kitchener1981 1d ago
Do you mean if they announced to the world about the Trinity Test? Japan did have a modest nuclear weapons program, but it was still in the laboratory with little results. The world's leading nuclear physists all knew about the concept and how much energy could be released by nuclear fission. The Manhattan Project boys even recognized the minute possibility of a cascade reaction that would destroy our atmosphere. The great debate is what was the greater concern? The third atomic bomb or the Soviet invasion of Japan? They knew that the Americans would be a better occupier than the Soviets. Yes, I know that the Soviets did not have the capability to launch an invasion, but the Japanese didn't know that.
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u/FerdinandTheGiant 1d ago
I will add, there is a solid case for the Soviets being able to invade Hokkaido.
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u/Intelligent_League_1 10h ago
Can you make it? They have almost no amphibious transports to make that gap
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u/FerdinandTheGiant 10h ago
To copy from an old reply:
The argument for a successful landing on Hokkaido comes from Richard Frank (author of Downfall) and Tsuyoshi Hasegawa (author of Racing the Enemy). Essentially, while the Soviets naval capacity was limited, it was adequate enough to move at least one division at a time with regard to a Hokkaido landing. While there were about 3 divisions of troops on Hokkaido, they were spread out across a large area and none of them were stationed near the intended Soviet landings spot, Rumoi. They would have had a nearly uncontested landing as around 1,000 troops were within 24 hours and the area did not have defenses. So it seems likely they could have established a beachhead. How it would go from there is far too speculative to make head way of in my opinion.
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u/FerdinandTheGiant 1d ago
I will add, there is a solid case for the Soviets being able to invade Hokkaido.
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u/theblitz6794 1d ago
Smartphones weren't widespread yet in 1945 so the effect wouldn't have been as shocking to the Japanese leadership without video and instant reporting.
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u/FerdinandTheGiant 1d ago
Depends on where and how they do it, but I think it’s reasonable to conclude such a bombing would be effective. My personal “suggestion” would be an unwarned strike of either the Tokyo Bay or a nearby forest followed by Russian entrance and an ultimatum. Based on the testimony of Kawabe, such a bombing likely would work to get a surrender.
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u/hatred-shapped 1d ago
Don't forget that even after they dropped the two bombs Japan still denied that they existed.
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u/RelativeIncompetence 23h ago
You have to be able to make a broadcast that would be believable to the relevant parties for it to have any intimidation effect...
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u/Tannare 22h ago
The idea to drop an atomic on a uninhabited island as a warning demonstration to be monitored by Japanese, Allied, and Neutral observers was discussed. Aside from the reasons given by others earlier, there was one more concern, namely that should Japan still refused to surrender, it may then make it very much harder for the planes carrying a bomb to make it to a Japanese city. Once they found out about the atomic bomb, the Japanese will be throwing suicide planes and as much flak as possible at every Allied plane in the future that flew towards their Home Islands. Delivering the atomic bomb by plane will then become either a mission impossible or just plain suicide.
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u/Princess_Actual 21h ago
Most people have not read into the invasion plans and the alternativea to nukes and/or the plans for the invasion.
It involved nerve gassing all the cities on Kyushu.
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u/merlin469 19h ago
What a lot of people don't realize, the bombs were never about the need to drop them. The war was good as won.
Shipping lanes were cut off. It was simply a matter of attrition at that point.
The bombs were dropped as retaliation for Pearl Harbor.
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u/Necessary_Mode_7583 17h ago
They didn't surrender after we fire bombed 30 some cities. They were cut off and starving . Even when they surrendered half of the big 6 wanted to keep fighting. There wasn't any demonstrate and they will give up. They had to be bent against their will.
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u/Thurad 14h ago
It would have made no difference. They surrendered due to the surprise attack on Manchuria by the Russians as much if not more so than the nuclear bombs. That basically forced them in to the unconditional terms of Potsdam that they had been trying to resist. As they’d end up losing everything anyway the final obstacle to surrendering was gone.
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u/IakwBoi 10h ago
A lot of commenters are here to tell you why america didn’t do a demonstration, but that doesn’t really answer your question. Your question is what would have happened if they had.
The Americans seriously considered doing a demonstration, and they could have if they wanted to. They hadn’t spend years on the Manhattan project to build a nuclear bomb, they’d spent years building two nuclear bomb factory lines. They were looking at something like 3 bombs per month being made, so they absolutely could have used one for testing in Nevada, one for a demonstration, and still destroyed plenty of cities, as long as they were okay moving back the schedule by a week or so.
Had they made a demonstration, would the Japanese surrendered? It’s obviously impossible to say for sure. Might it have worked? Sure. Japan was in a horrible situation, only zealots wanted to keep fighting, they were putting out feelers to neutral countries (Russia in June or July, I can’t remember exactly which month) to negotiate surrender to the allies.
When they Hiroshima was destroyed it was days before the government realized and really beloved the scale of the destruction, by then Nagasaki had also been attacked. There is a point of view that says one attack was all that was “needed”, but Japan took a while to surrender, and the second attack was essentially unnecessary. This isn’t certain, but some people think so. So if we can’t be certain two attacks were needed, can we be certain one was needed?
The major sticking point for surrender among most Japanese leadership (zealots aside), was the emperor. The allies demanded “unconditional surrender” at Potsdam, the Japanese wouldn’t accept the emperor being kicked to the curb, and they surrendered after it was communicated to them that “unconditional” still meant the emperor could stay. They’d been operating under the opposite assumption, and the clarification didn’t come until after the two nuclear attacks. Would they have surrendered after a demonstration, had they understood that surrender would have meant the emperor could stay? Tantalizing, but again, impossible to say.
Immediately after the war a dogma was decided on in America. The dogma was that the nuclear attacks were horrible but necessary. This was at a time when there was a lot of anxiety about the role and use of nuclear bombs, and about the rebuilding of Japan. Every comment you read on the necessity of the nuclear attacks comes out of that context, so look for talk about death rates in China, projected casualties from an invasion, and starvation rates whenever you ask about the nuclear bombings.
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u/ijuinkun 4h ago
On the larger scale of human war doctrine in general, nukes were something that had to be used “once, but never again”. If no nuke had ever been used on an inhabited area, then no one would appreciate just how horrible they are, and we might have gotten a much larger scale use during the Korea war, like General MacArthur had wanted to do.
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u/Artistic_Bit_4665 9h ago
Look at it this way. Japan did not surrender until TWO bombs had been dropped. The first was not enough. The USA had to prove that they had more than one, and would continue the devastation. So..... no. You don't get a bully to stop by punching someone else. You get a bully to stop by punching the bully.
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u/SideEmbarrassed1611 9h ago
They debated it. Showing it off comes off as a bluff. Japan would say we were too scared to actually use it and then we have to use it anyways.
The decision was made to drop the two reserve bombs after the Gadget was detonated at Trinity Test Site. The United States does not bluff.
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u/Happy_Brilliant7827 5h ago
We kinda did. All nuclear tests are overt shows of force. Its why we put them in the newspaper in those days.
Also, everyone overlooks that when we dropped the first nuke on Japan, we told them we were going to drop them until they surrendered.
It took two bombs.
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u/Serious-Collection34 3h ago
Imagine is you and your neighbor were fighting and he threatened you with a cannon, you would be like there’s no way he has a cannon
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u/MonumentalArchaic 2h ago
I don’t think Japan would really care, the fire bombings brought many times more devastation than any amount of nuclear material the us could possibly assemble.
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u/dinkleberrysurprise 2h ago
I’ve seen a lot of accurate answers but here’s one interesting reason I heard posited recently: if you tell the Japanese in advance where the bomb would be dropped, they could conceivably transport allied POWs to that location in advance, in an attempt to forestall the drop.
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u/tomplum68 15m ago
the us dropped the first on an inhabited city and that didn't work. why would dropping it on some random island have worked better?
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u/Rear-gunner 1d ago
This was extensive discussed before dropping the bomb. There wee big problems, the first is no one was sure it would work, what if in the demonstration it did not work, no one was sure how much power it had, what if to test its power the Japanese used Chinese or allied prisoners and it was felt that it would be too hard to show the power of the bomb, measuring it out etc.
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u/FerdinandTheGiant 1d ago
It was far from extensively discussed. The Interim Commitee self admittedly barely touched on the subject. One of the members (Bard iirc) claimed they only discussed it for 10 minutes before dismissing it out of hand.
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u/Rear-gunner 23h ago
There was more than just this committee. Earlier, the Target Committee had discussed it. Plus, the interim committee had several meetings. Interestingly, in the end, the pilot was allowed to pick point zero.
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u/FerdinandTheGiant 22h ago
I’m aware there were multiple meetings but you won’t find it discussed at any length in any of them. I mention the Interim Committee because they were in part put together to address concerns raised by scientists about the usage of the bomb on cities.
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u/Rear-gunner 22h ago
As i stated, there were several committees, eg, Franck Report that discussed it too, but I am not sure how much authority it was given.
Put it this way, it was discussed and found impractical
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u/SoSoDave 1d ago
Even if Japan surrendered before the first bomb was dropped, the USA wouldn't have accepted it.
The USA wanted to know what the bombs would do to actual people in actual cities.
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u/kimj17 1d ago
They even had fears that the fission would start a chain reaction and burn the earths atmosphere so they kinda yolod it
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u/canman7373 1d ago
It was tested privately before it was used on Japan so that was already disproven.
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u/SuDragon2k3 1d ago
At the time, America had exactly two bombs, of different types, assembled. They didn't have enough to do a demonstration drop, do a war drop and have a reserve.
Fat Man was an implosion type weapon and Tall Boy was a 'gun' type weapon. Two methods in case one fails. The US was gambling experimental technology versus an invasion that'd wound or kill over a million troops.