Transcript of taped conversations among German nuclear physicists (1945)

https://ghdi.ghi-dc.org/sub_document.cfm?document_id=2320

by davidbarker • 3 years ago

305 283 3 years ago

sdfghswe• 3 years ago

WEIZSÄCKER: I think it's dreadful of the Americans to have done it. I think it is madness on their part.
HEISENBERG: One can't say that. One could equally well say "That's the quickest way of ending the war.”

mikewarot• 3 years ago

Without perspective, it's easy to say that the bomb shouldn't have been used. Once one learns of the other details of the war, and gains perspective, it's obvious that it was going to be used.

We're still awarding the Purple Heart medals that were produced in vast quantities in WW2 in expectation of the invasion of Japan. (or so I've heard)

lloydatkinson• 3 years ago

I might be misremembering but I think the ribbons are new but the medal itself is the original new ones

croes• 3 years ago

But they used two bombs. Wouldn't one have been enough to end the war?

wk_end6• 3 years ago

My feeling is that dropping the bomb was overall better than a land invasion, but I find the arguments against at least giving the Japanese a demonstration of the bomb - even just the footage of the Trinty test - beforehand fairly weak.

Yes, it's likely - given the Imperial Japanese military's overall disposition - that it wouldn't have been enough to cause them to surrender, in which case using the bomb on a target would be the next step. And yes, advance notice might have made those operations more difficult. But given the horror it unleashed on innocent civilians, I think the Allies had a moral obligation to try it.

throwaway2903• 3 years ago

It's still easy to say that the bombs shouldn't have been dropped, for one because it's a war crime and indiscriminate murder of civilians.

Just ask what if a country that did it lost the war. People would probably be put to death just for this in Nuremberg.

underlipton2• 3 years ago

Once one learns of the other details of the war, and gains perspective, it's obvious that it was going to be used.

That doesn't prove that it should have been used. It was also not a given even a year earlier. If Henry A. Wallace had remained Vice President, it's likely his lack of antagonism towards the Soviets would have led him to avoid the show-of-force that the bombings were. The moment separating 150,000 Japanese civilians from life and death is the one where the DNC went behind the backs of the American people and chose Truman, chip-on-his-shoulder and all, to be FDR's last running mate. We're still paying for that bit of hubris.

twirlip• 3 years ago

I wonder if the horrific aftermath of the atomic bombs dropped on Japan prevented later usage of nuclear weapons.

ookdatnog3• 3 years ago

I listened to this >2h essay about the atomic bombing over a year ago. I'm writing mostly from memory, so there might be errors in my summary.

I think the argument was that the reason for the atomic bombing was not really a military necessity (fleet admirals Leahy and Nimitz at least seemed to think so). The Japanese were already signaling they were willing to surrender well before the bomb dropped -- but not yet _unconditionally_. The one condition they had was that the emperor had to stay in place and should not be punished for the war. The US could have chosen to accept this condition and end the war, but didn't for a variety of reasons (none of them military).

https://www.youtube.com/watch?v=RCRTgtpC-Go

lo_zamoyski• 3 years ago

Why the bombings of Hiroshima and Nagasaki were gravely immoral[0].

[0] https://catholicherald.co.uk/ch/weigels-terrible-arguments/

NoMoreNicksLeft2• 3 years ago

The US government didn't drop the bomb to avoid a violent invasion. They were half-sure they might get an easy surrender anyway.

They needed to show the Soviets what they could do. It was 100% a demonstration. The Soviets knew about it of course, but no one had really seen what it could do.

And if it helped end things early enough that the Soviets didn't invade themselves and partition Japan as they were already starting to do in Germany, then that was a bonus.

Whether it was morally sound to use it to intimidate Stalin is another question entirely, and I don't know what the answer is. But let's not pretend that it was some balance sheet calculation about how many lives would be lost... it was never that.

gettodachoppa• 3 years ago

I used to believe the American feel-good propaganda that "we just had to nuke the Japanese, OK? We saved more lives.".

Then I gained perspective, and learned that Japan's navy had been entirely wiped out (EDIT: and the air force) the Japanese were trying to negotiate a surrender, but the US wouldn't budge on something as minor as allowing to keep Hirohito as figurehead emperor (which they eventually did after they surrendered after the nukes).

It was racism, plain and simple. Actually, it's more than racism, I'm not sure that word explains it. This isn't the relatively mild white-on-black racism of 1940s America. This is a much different level of racism, where Americans saw the Japanese as complete subhumans not even worth morally debating over. The Americans spent years building those bombs, so they must have thought it was anti-climactic not to try them. They didn't want to use them near the white people in Europe, so who best than a remote island of people you don't even view as humans, to the point where you put your own citizens in internment camps for sharing an ethnicity with them?

But I see so many Americans clinging to the myth that the nukes were a utilitarian moral choice. Admitting the truth to themselves would raise some questions about their country which clash with the perception they have.

kleton• 3 years ago

Japanese command conveyed surrender offers through Macarthur months before the battle of Okinawa. The terms they offered were substantially the same as what terms America set upon their final surrender- full surrender, but with the institution of emperor remaining intact as a puppet of the American occupation government.

dr_dshiv• 3 years ago

Amazing and well worth reading the whole thing.

lqet2• 3 years ago

HEISENBERG: [...] I believe this uranium business will give the Anglo–Saxons such tremendous power that EUROPE will become a bloc under Anglo–Saxon domination. If that is the case it will be a very good thing. I wonder whether STALIN will be able to stand up to the others as he has done in the past.

[...]

WIRTZ: It seems to me that the political situation for STALIN has changed completely now.
WEIZSÄCKER: I hope so. STALIN certainly has not got it yet. If the Americans and the British were good Imperialists they would attack STALIN with the thing tomorrow, but they won't do that, they will use it as a political weapon. Of course that is good, but the result will be a peace which will last until the Russians have it, and then there is bound to be war.

jxramos• 3 years ago

Wow, this Weizsacker fellow predicted the https://en.wikipedia.org/wiki/Potsdam_Conference pretty much?

Sounds like it was this individual https://en.wikipedia.org/wiki/Carl_Friedrich_von_Weizs%C3%A4...

lqet2• 3 years ago

His brother was president of Germany from 1984 to 1994. It's quite an illustrious family [0].

[0] https://en.wikipedia.org/wiki/Weizs%C3%A4cker_family

hh3k02• 3 years ago

KORSCHING: "I would rather take Swedish nationality than stay in GERMANY and wait for the next war. On the other hand I would not make any effort to become British. If there is nothing more to be made out of GERMANY, one should at anyrate get away from RUSSIA."

shpx2• 3 years ago

Could you spell out what specifically you find significant about this quote?

nl3• 3 years ago

The context here is that the German scientists thought it likely that Germany would be completely taken over by Russia (because the Western advance has stalled).

legitster2• 3 years ago

I recently listened to the Hardcore History about atomic weapons and I hadn't realized how right as WWII ended everyone was ready to wage nuclear war against Stalin immediately.

myth_drannon2• 3 years ago

Knowing that US was supplying USSR with weapons,airplanes, trucks and helping build entire factories right up until the end of the war and then wanted to nuke the same ally is really buffling. One one hand can be said, yes they wanted USSR to bleed fighting Germany (or do the harder fighting part) on the other hand it's just confusing and possibly different fractions within US government wanting different things.

hef1989811• 3 years ago

Only that right after WW2, nuking the Soviets wouldn't have helped. The Red Army had Berlin, had shorter, and well established, supply lines, and the numbers. Nuking Moscow had caused WW3 right after WW2 ended, the Soviets woupd have ended up controlling Germany, and propably other countries. Because a hand full of small nukes wouldn't have been that decisive.

The are reasons Operation Unthinkable wasn't launched. But one has to admit, the anti-communist propaganda that united people from Patton, McCarthy all the way to former Wehrmacht Generals, still has long lasting effects even today.

hirundo• 3 years ago

Weizacker wasn't alone in that opinion:

  [John] Von Neumann was, at the time, a strong supporter of "preventive war." Confident even during World War II that the Russian spy network had obtained many of the details of the atom bomb design, Von Neumann knew that it was only a matter of time before the Soviet Union became a nuclear power. He predicted that were Russia allowed to build a nuclear arsenal, a war against the U.S. would be inevitable. He therefore recommended that the U.S. launch a nuclear strike at Moscow, destroying its enemy and becoming a dominant world power, so as to avoid a more destructive nuclear war later on. "With the Russians it is not a question of whether but of when," he would say. An oft-quoted remark of his is, "If you say why not bomb them tomorrow, I say why not today? If you say today at 5 o'clock, I say why not one o'clock?"

https://cs.stanford.edu/people/eroberts/courses/soco/project...

nequo• 3 years ago

Von Neumann deserves tremendous recognition but not for his sense of diplomacy.

raverbashing2• 3 years ago

Imagine that. He probably had the calculations in a 4x4 grid matching the possibilities already

I think he might be on to something ;)

ttflee3• 3 years ago

Fun fact: hardcore xenophobic narratives in China has been using the term Anlgo-Saxons (昂撒), in recent years.

mseepgood• 3 years ago

Russian propaganda as well.

BlueTemplar2• 3 years ago

Why wouldn't they ?

wirrbel• 3 years ago

German Angelsächsisch (literal translation is Anglo Saxon) is typically used in German as an umbrella term for the English speaking world, so Britain-USA-commonwealth is covered by it. While it is used sometimes to “other” the English speaking world it does not lend itself as easily as other terms for xenophobia because three German regions are actually called Saxony (Lower Saxony and (upper) saxony, saxony-Anhalt. Xenophobic speech in German would often refer to “der Engländer”, or “der Amerikaner” (the Englishman, the American)

dkarp• 3 years ago

It's not clear to me if the full transcripts are available here but I found the book of transcripts at my college library during my studies and found it fascinating.

Looks like you can now buy it on amazon: https://www.amazon.com/Operation-Epsilon-Farm-Hall-Transcrip...

cobaltoxide• 3 years ago

Of note, these are the translations of the transcripts. The original transcripts unfortunately were not preserved.

netsharc• 3 years ago

Off-topic: I didn't like the serif font so opened Dev Tools to modify the CSS for more comfortable reading. I'm amazed, the page is a giant TABLE, it uses BODY BGCOLOR, so a 90's style web design. There's CSS being used though.

I guess it's an institute dependant on grants, where they can't just blow money on a website redesign...

myth_drannon2• 3 years ago

I wouldn't give any importance to those transcripts. They were all aware that the captors are bugging them and they were just playing the innocent scientists that worked for the sake of advancing science and they are not infact proud members of the Nazi Party.

Animats3• 3 years ago

HEISENBERG: "Microphones installed? (Laughing) Oh, no, they're not as cute as all that. I don't think they know the real Gestapo methods; they're a bit old fashioned in that respect." [1], p. 13.

[1] https://pubs.aip.org/DocumentLibrary/files/publishers/pto/co...

jacquesm10• 3 years ago

Fascinating how the people that they were discussing were having their ear to the wall. It makes you wonder to what extent they were doing this because they were aware of being eavesdropped on or if they were really so naive as to discuss how best to influence the people that they were utterly dependent on.

Edit: I've read some more of the transcript and what really is interesting is that they are so aloof from the realities of the situation they are in. Almost conceited.

bee_rider4• 3 years ago

Although, that is also exactly what you’d say if you were trying to manipulate the listeners.

whimsicalism11• 3 years ago

I'm assuming we're all reading this as evidence for GPs point, not that they were unaware of the possible.

matthewdgreen4• 3 years ago

What's important about the recordings is that they were stunned at the news about Hiroshima, and declared it impossible. Heisenberg's own calculations had predicted a much larger critical mass. If they were acting, apparently they're amazing actors.

Animats3• 3 years ago

Wasn't this on HN last year?

This is just a summary from the day the Germans found out about the bomb. The full transcripts are available.[1][2][3] Unfortunately, the recordings were not kept. They were not on magnetic tape; they were recorded on shellac records. Only the interesting parts were transcribed.

The conclusion of the US Alsos mission to investigate the German bomb program: "It was so obvious the whole German uranium set up was on a ludicrously small scale. Here was the central group of laboratories, and all it amounted to was a little cave, a wing of a small textile factory, a few rooms in an old brewery. To be sure, the laboratories were well equipped, but compared to what we were doing in the United States it was still small-time stuff. Sometimes we wondered if our government had not spent more money on our intelligence mission than the Germans had spent on their whole project."

[1] https://pubs.aip.org/DocumentLibrary/files/publishers/pto/co...

[2] https://pubs.aip.org/DocumentLibrary/files/publishers/pto/co...

[3] https://pubs.aip.org/DocumentLibrary/files/publishers/pto/co...

bandrami• 3 years ago

Oppenheimer hadn't just come out last year

dredmorbius• 3 years ago

Not precisely this item AFAICT. Searching "German physicists" and "Farm Hall" turns up some earlier items.

There was a Kottke post about this in 2019. One year, four, same thing.

<https://news.ycombinator.com/item?id=20659607>

This looks to be the same transcript, also from 2019:

<https://news.ycombinator.com/item?id=19113443>

And from 2016. You have several of the top comments:

<https://news.ycombinator.com/item?id=12568250>

And a discussion about the event from July 2022:

<https://news.ycombinator.com/item?id=32164657>

<https://pubs.aip.org/physicstoday/Online/5401/The-elusive-tr...>

wkat4242• 3 years ago

It was so obvious the whole German uranium set up was on a ludicrously small scale. Here was the central group of laboratories, and all it amounted to was a little cave, a wing of a small textile factory, a few rooms in an old brewery. To be sure, the laboratories were well equipped, but compared to what we were doing in the United States it was still small-time stuff

Thank God the Germans didn't realize the potential there or the world would have looked very differently now. It's not as if they didn't have the technical chops to make something like this work. They even had working jet fighters.

Sometimes I wonder if Heisenberg secretly took them on the scenic route. Because his whole uranium cubes on strings thing looks a bit contrived.

janmo• 3 years ago

Unknown to the allied until the very end of WWII, nazi scientists had discovered by accident a multitude of nerve agents before and during the war including in 1938 the now very infamous Sarin gas.

Despite having been mass produced and being ready for use during the entire war, it luckily never was. Had it been, it is likely the war would have lasted much longer and would have been much deadlier, it is also likely the first nuclear bomb would have been dropped on Berlin.

When WWII came to an end most of the supply and manufacturing plants were captured by the soviets and put back into production.

1964 US Army Training Film : https://www.youtube.com/watch?v=p2O5ndVkNKk

NY article: https://www.nytimes.com/2017/04/12/science/sean-spicer-hitle...

pugworthy• 3 years ago

I'm surprised to find little information online about Dr. Hans Bomke, whom I presume is the "BOMKE" referenced a few times. He was not well liked it seems.

I have seen references about a US FBI file on him (Bomke, Hans 424771), also that he did do some co-research with Otto Hahn.

Paul Lawrence Rose's book "Heisenberg and the Nazi Atomic Bomb Project" say that the others at Farm Hall considered him a Nazi plant.

underlipton2• 3 years ago

This reads in some ways like American urbanists discussing Chinese infrastructure and the building boom.

beebmam• 3 years ago

KORSHING: That shows at any rate that the Americans are capable of real cooperation on a tremendous scale. That would have been impossible in Germany. Each one said that the other was unimportant.

Say what you will about the US, and it certainly has its faults, but the Americans, both the private sector and public sector, have certainly figured out how to coordinate with others towards a goal.

The ability to coordinate with others seems like a more valuable quality than virtually any other in a serious project, in my experience.

oaktowner• 3 years ago

I don't disagree with the sentiment, but I do believe that Americans ability to cooperate (both with each other in general and between the private and public sectors) is not now what it was in the mid-20th century.

afavour2• 3 years ago

I’d say the COVID vaccines are an example showing what’s still possible. Not to discount the Astra-Zeneca vaccine in the UK of course.

Public acceptance of those vaccines is another story, of course…

TulliusCicero6• 3 years ago

I mean WW2 was a particularly cooperative time for the US.

rsync• 3 years ago

Disagree.

If you were in Manhattan the first week after 9/11 you witnessed tremendous solidarity and cooperation.

It was, in some small way, life changing to witness.

portmanteur• 3 years ago

Besides large scale immigration, what changed in America? Complacency during peacetime?

wddkcs• 3 years ago

Is it 'figured out' or is cooperation an emergent principle in democratically free societies? Many factors involved, but these kinds of society level observations are better ascribed to political bodies, rather than physical minds

bloak• 3 years ago

A minor point of pedantry (sorry, I can't help my obsession with textual criticism): these are not transcripts; they are translations. I think I read somewhere that transcripts were made, but they were lost. I find it odd that the introduction says nothing about that. On the other hand, the introduction doesn't really say anything much at all about the provenance of the text. Or perhaps it does and I didn't look hard enough. If anyone knows more, please reply.

vibrio• 3 years ago

I don’t think that is pedantry. Translations are interpretations by a third party that may or may not have an opinion on the topic.

kristianp• 3 years ago

Surely more correctly, they would be translations of transcripts of recordings.

graycat• 3 years ago

WWII? The atom bombs on Japan? I tried to understand the history, causes, read the Richard Rhodes books, other books, watched documentaries and movies, etc.

As I read this thread, I guess that it has more and better thinking about the issues of morality, ethics, various steps that could have been attempted with Japan, atomic weapons stopping wars, etc. than Truman considered when he decided to drop the bombs and conclude that Truman saw just two cases: (1) Drop atomic bombs, end the war within not many hours, and save lives of US soldiers. (2) Delay, attempt, look for alternatives and possibilities, negotiate, demonstrate, ..., and lose more US lives. So, he picked (1), and maybe he did it in less than 10 minutes.

TulliusCicero6• 3 years ago

Saving American lives was probably the dominant factor, but Americans expected that a land invasion would also kill millions of Japanese, far more than the atomic bombs.

whimsicalism11• 3 years ago

There are strong indications that a surrender would occur regardless and why would the only alternative to a land invasion of Japan be dropping two nuclear bombs on Japanese cities.

credit_guy2• 3 years ago

HEISENBERG: I don't believe a word of the whole thing. They must have spent the whole of their £500,000,000 in separating isotopes; and then it's possible.

How did Heisenberg know with such an accuracy the budget of the Manhattan project? Wikipedia states that it was $2.2 billion, and the pound/dollar exchange rate during the war was $4.03 for £1, so Heisenberg was less than 10% off.

Edit: I think all these discussions must have happened after they heard Truman's speech [1], where he quoted the pricetag of 2 billion dollars.

[1] https://millercenter.org/the-presidency/presidential-speeche...

P_I_Staker• 3 years ago

Interesting that the pound did so much better during such dire times for the UK, in the mist of a fight to the death, it was losing.

cameron_b2• 3 years ago

HEISENBERG said he could understand it because GERLACH was the only one of them who had really wanted a German victory, because although he realized the crimes of the Nazis and disapproved of them, he could not get away from the fact that he was working for GERMANY. HAHN replied that he too loved his country and that, strange as it might appear, it was for this reason that he had hoped for her defeat.

This is the difference between Nationalism and Patriotism

tailspin2019• 3 years ago

Yes the most fascinating part of this for me was the different ways that they each tried to reconcile their love of their country, of science, of the desire to further technological progress for its own sake, and the desire to do what’s “right” (with differing viewpoints about what “right” in this context actually meant).

whimsicalism11• 3 years ago

They all undoubtedly suspected they were being recorded at this point and the war was already lost. Would be curious what their opinions actually were during the peak war years.

colinflane• 3 years ago

I just finished reading McCarthy's 'Stella Marris' and 'The Passenger'. Anyone who enjoyed reading this linked transcript I imagine might also appreciate much of the themes treated in McCarthy's final works. I found the passages on Oppenheimer interesting especially in light of Nolan's new film. Funny timing.

photochemsyn• 3 years ago

Several points to consider:

1. While much has been made of the theoretical physical effort at Los Alamos, without the Oak Ridge, TN and Hanford, WA chemical-physical production lines for uranium-235 and plutonium, bomb production would not have been possible.

2. These efforts required vast inputs of energy, mostly provided by hydroelectric projects such as TVA for the Oak Ridge uranium effort. It's highly implausible that such efforts would have succeeded in wartime Germany no matter how many resources were diverted to them. One bombing run would have wiped out the whole enterprise - and of course, neither Oak Ridge nor Hanford were subjected to aerial bombardment.

3. The Germans apparently were more interested in a nuclear rocket engine or some such than a nuclear bomb, by most accounts I've read. Also, their heavy water project in Norway was effectively sabotaged.

Note also, many scientists involved with the bomb project quit as soon as they learned Germany was defeated and so the rationale of beating the Germans to the bomb no longer made any sense.

FDR, if he hadn't died early, would almost certainly have rejected the use of the bomb against Japan, for the same reasons that he rejected the use of poison gas against the Japanese holdouts on Iwo Jima and Okinawa. If the Japanese had simply been given the option to retain their figurehead Emperor, they'd have certainly surrendered rather than accept the occupation of northern Japan by Russian forces in a replay of East Germany.

Isn't history fun?

ProjectArcturis2• 3 years ago

Note also, many scientists involved with the bomb project quit as soon as they learned Germany was defeated and so the rationale of beating the Germans to the bomb no longer made any sense.

Joseph Rotblat did. There weren't any others, let alone "many".

FDR, if he hadn't died early, would almost certainly have rejected the use of the bomb against Japan, for the same reasons that he rejected the use of poison gas against the Japanese holdouts on Iwo Jima and Okinawa.

I think most historians would strongly disagree with this.

SonicScrub• 3 years ago

If the Japanese had simply been given the option to retain their figurehead Emperor, they'd have certainly surrendered rather than accept the occupation of northern Japan by Russian forces in a replay of East Germany.

Do you have a source for a historian arguing this point? If so, I'd be curious to read it. My own (albeit, purely hobbyist level) understanding on this is that this would almost certainly not have been the case.

pests3• 3 years ago

One bombing run would have wiped out the whole enterprise

Which is exactly what happened to the small nuclear program Japan was attempting.

ThrowawayR2• 3 years ago

"...If the Japanese had simply been given the option to retain their figurehead Emperor, they'd have certainly surrendered..."

There was a barely averted coup (https://en.wikipedia.org/wiki/Ky%C5%ABj%C5%8D_incident) to overturn Hirohito's decision surrender so that is clearly incorrect. The military, who was in control of the Japanese government, wanted to continue the war even after the use of both atomic weapons.

housecarpenter• 3 years ago

How does that contradict what you quoted? The claim is that if the Japanese had been able to conditionally surrender, with the condition of retaining their emperor, then they would have done so. You respond by pointing out that when the Japanese did eventually unconditionally surrendered, much of the government was still against that decision. That implies nothing about what their response would have been to a conditional surrender. It's just a non sequitur. If anything one would expect that there would have been less elements of the government resisting a conditional surrender and so the coup would have been more likely to be suppressed in that case.

fsckboy2• 3 years ago

interesting aside: "wiseacre", a word in English which I heard when I was a kid, don't hear it so much any more:

wiseacre means "one who feigns knowledge or cleverness; one who is wisecracking; an insolent upstart." If you made a joke somebody might say "oh, a real wiseacre, eh?"

seeing Weizsäcker's name I was struck by the similarity so I thought I'd look it up, and turns out the two words have the same etymology: soothsayer, wise man

wiktionary From Middle Dutch wijssegger (“soothsayer”), from Old High German wīzzago, wīzago (“wise man, prophet, soothsayer”), from Proto-West Germanic *wītagō (“wise one; prophet”). Cognate with Old English wītga (“wise man, prophet”). See also German Weissager (“soothsayer, seer”).

https://en.wiktionary.org/wiki/wiseacre

ProjectArcturis2• 3 years ago

Interesting coincidence that the German Weissager arrived at a similar meaning and sound. Its etymology is wissen (to know) - Sager (sayer).

jtsuken• 3 years ago

Sorry to disappoint you, mate. Weizsäcker is much more likely to be an equivalent of Wheatbagger.

Weizen - wheat Sack - bag

fsckboy2• 3 years ago

i am disappoint! you're a good freund, bc you didn't choose this moment to teach me the meaning of schadenfreude.

fishtockos2• 3 years ago

On the prospect of working on a "Uranium-Engine"

Every layman can see that these ideas are exceedingly important. Hence there won't be any money in it. You only make money on ideas which have escaped the general public. If you invent something like artificial rubies for the watch-making industry, you'll make more money than with the Uranium-Engine

After hearing news of the bomb

That shows at any rate that the Americans are capable of real cooperation on a tremendous scale. That would have been impossible in Germany. Each one said that the other was unimportant.

credit_guy2• 3 years ago

Very interesting read. I read it all, and it looks to me none of the German scientists had any clue that you can build a plutonium bomb. They kept talking about 235 (i.e. Uranium-235), about isotope separation, but not a single hint that you could transmute U-238 into Pu-239 and then make a plutonium bomb.

What's not appreciated about the Manhattan project is that not only the US made a bomb, it made two, meaning two completely different designs. And they were aware of a third one: Glen Seaborg (the discoverer of plutonium) has investigated the feasibility of making a bomb from Uranium-233 [1]

  > Seaborg viewed uranium-233 as a potential backup to plutonium-239

So the US could have made bombs of three different designs, it just got confident enough that 2 will work out in the end. Of course, 10 years later (in 1955) it did build and test a U-233 bomb just to see that it's possible.

[1] https://trace.tennessee.edu/utk_gradthes/2758/

Animats3• 3 years ago

Right. They didn't even know plutonium existed. It was discovered in 1941, at U.C. Berkeley's cyclotron, and kept secret.

kstrauser• 3 years ago

That’s nightmare fuel: finding out that your enemy is making physics bombs out of elements you weren’t aware of. It’s the plot of an X-Files or something.

WalterBright3• 3 years ago

Some years ago I saw a documentary on TV that claimed that the Japanese had their own bomb program, and in the final days of the war actually detonated a small device. With the defeat they disbanded and destroyed the evidence of it.

I've never seen any hint of this before or since. Has anyone else?

mattnewton• 3 years ago

Wikipedia has a detailed description of the program https://en.m.wikipedia.org/wiki/Japanese_nuclear_weapons_pro...

Looks like they never got sufficient quantities of U-235 to attempt a detonation.

WalterBright3• 3 years ago

Ah, thanks!

Also: https://en.m.wikipedia.org/wiki/Japanese_nuclear_weapons_pro...

Full_Clark• 3 years ago

HARTECK: [...] we would have needed to employ 50 workmen continuously in order to produce two tons a year. If we wanted to make ten tons we would have had to employ 250 men. We couldn't do that.

WEIZSÄCKER: How many people were working on V 1 and V 2?

DIEBNER: Thousands worked on that.

---- Diebner is omitting HOW they got that workforce up into the thousands. Many who worked on V-1 and V-2 rockets were prisoners who were literally worked to death.

whimsicalism11• 3 years ago

Likely comparably humane to the US sourcing almost all of its WWII uranium from the Belgian Congo

apexalpha• 3 years ago

Very interesting post, thank you.

Transcript of taped conversations among German nuclear physicists (1945)

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