Hitler believed in rockets, dismissed A-bomb research – Nuclear historian Richard Rhodes

SS: So, did German scientists like Nobel laureate Heisenberg who was feared so much by the Americans and the British, deliberately mislead their government about the difficulties of building the bomb - was it an act of resistance to Nazism, a kind of sabotage?

RR: Well, they claimed so after the war. But there's a good deal of evidence that in fact they simply made some stupid mistakes. When Heisenberg and the other German scientists who were interred in England in 1945, when they heard the news of the Hiroshima bombing, they turned to Heisenberg and said: "Well, how much uranium must they have used?", and he said it would've required several tonnes - which means he has never got beyond thinking in terms of a nuclear reactor, and hadn't realised that if you pulled out that special form of uranium that's used in bombs, U-235, that the amount would actually be measured in a few kilograms, not in tonnes. So, there's every sign that he really didn't intend or try to build the bomb. They diverted to working on a nuclear reactor, and by the end of the war had about a half scale reactor, moderated with heavy water. If they've built one twice the size that the one they were working on..., but they didn't have enough heavy water and they didn't have enough uranium. So it's pretty clear that mistakes and other problems got in the way of German bomb.

SS: In any case, the officials of both Germany and Japan looked at the amount of work required for the Bomb and concluded it couldn’t be done by anyone. Was it just arrogance - “if we can’t do it, no one can”?  How could they underestimate the Allies so much?

RR: Well, it certainly was the arrogance on the German part in particular, but the Japanese investigated working on the bomb and realized that to separate the special isotope of the uranium would require more than their entire national electrical supply and more than their annual production of copper for wires!

SS: On the other hand, the Americans and the British, were sure the Germans were working on the bomb - and even that they are years ahead. Was it this fear of German scientific might that drove the Allies to really commit to the project? 

RR: It was, I think, most of all, the reason why first England and then the U.S. became involved in working on the bomb - exactly because they knew that the German scientists who were left after the Jewish scientists were expelled from Germany, they knew that German scientists were immensely competent, and simply assumed that the government would be interested. But, of course, that's not how it turned out. We didn't know until, I think, it was pretty late, in 1944, that Germany was not working on the bomb. So that's really what drove the American program.

SS: Building a bomb required enormous funds, which countries involved in WW2 could barely afford to invest, at least not until they were certain that a bomb could be built. Was it the scientists who had to convince gov’ts to start work - or the gov’ts pushing the scientists to make it happen? Which way around?

RR: I spoke with one of the Soviet Union and Russian scientists, in 1992 - Viktor Adamsky, one of the men who worked on the Russian hydrogen bomb. And Adamsky said something very wise - he said, "in order to get the point of building the bomb, governments had to trust their scientists and scientists had to trust their government, because you wouldn't go directly to the bomb, you had to go by way of building this enormous physical plant in order to enrich uranium, or an alternative path, it was quickly discovered, which was to build a nuclear reactor and make plutonium - either way there was an enormous investment involved, which might not turn out to make the bomb! So there had to be trust on both sides. And there wasn't that trust, really, in Nazi Germany, but there was that trust in the United States.

SS: Exactly, so how did the government like the American government decide to dedicate its whole industry to the project that could very well fail? Where did the trust come from?

RR: Well, because Franklin Roosevelt who was President at the time was an educated and highly intelligent man, he had been in connection with the scientific establishment in the United States, directly and indirectly for many years. And it was possible, drawing on that organisation, if you will, that loose connection among these various academics and other scientist, to show him step-by-step on paper, at least, that this project would have an immense effect on the war. The man who later on led the actual physical work on the bombs itself, Robert Oppenheimer, when he recruited scientists for this top-secret program, he used to tell them: "I can't tell you what we'll be doing, but I can tell you that it will probably end the Second World War. And it may end all war." - so, in that sense, I think that the government...

SS: So were these scientists actually eager to take on a job of building a weapon of mass destruction? Or they were just thinking they were helping end the war - what was the case?

RR: They were eager to beat Germany to a bomb, because it was clear that a bomb could not only bring victory, but could even reverse defeat, and, in addition, in the larger view that Oppenheimer presented to them, they thought that this might be a contribution to a world without the World War - because the weapon would be so destructive that it would make it impossible for countries with such weapons to ever go to war with each other. That was the idea, the larger idea, behind what they were doing. They were, of course, perfectly aware that they were working on a weapon that would be immensely destructive. I don't know that they have actually thought through the way it would be used...

SS: ...Used afterwards, yes. So, according to a declassified US army report in 1945, Nazi agents tried to sabotage atomic labs power generators on one of the Manhattan project. Were there other physical attacks on the atomic infrastructure, attempts to derail  American atomic efforts? 

RR: The only one I'm really aware of... In fact, I wasn't aware of the nazi one that you just mentioned. But, the japanese flew some hot-air balloons, paper balloons across the Pacific that had explosives hanging below them, with the hope that jet stream would carry those balloons into the United States and destroy whatever they might hit. And one of them, actually, took down a power line that was supplying energy to the plutonium separation factory in Washington states, on the Pacific coast of the United States, and actually shut the plant down for 24 hours, until they got another electric line up. That was purely coincidental, really. I don’t think that anyone came, to actually sabotaging anything.

SS: Less than a month passed between the bomb test, and it's dropping on Japan. Did the US know the catastrophic consequences the bomb would unleash when the decision was made to bomb Hiroshima? 

RR: Yes and no. I mean, one of the bombs has been tested, but it was tested in the desert in the Southeastern United States, and although it was obviously an enormous explosion, one of the people who observed said "We really didn't think about this weapon being exploded over a city". The people at Los-Alamos, where the bombs were built also assumed that there would be some kind of...that the Japanese would go to the bomb shelters as they did whenever fleet of bombers flew over to bomb a city, but of course, this was just going to be one plane, and the Japanese in Hiroshima assumed it was a weather plane, flying over to check the weather before a fleet of bombers might arrive. So, I don't want to excuse them, I mean, the American policy was mass firebombing of Japanese cities. Every city in Japan of more 50,000 population had already been firebombed to utter destruction. The only reason Hiroshima and Nagasaki were around to be atomic bombed is that they have been set aside as targets by the United States air force. So, there's no question that the military leadership certainly was aware of what it was doing, but it have been doing that with conventional firebombing for the previous 10 months.

SS: Why did the US wait several days in between the Hiroshima and Nagasaki bombings? 

RR: There was an effort, once the catastrophic destruction caused by the Hiroshima bombing became clear, to everyone, there was an effort to alert the Japanese people - millions of leaflets were dropped by plane between August 6th and August 9th - the Nagasaki bombing - that said, basically, "Ask your leadership what happened at Hiroshima". There was some attempt, however limited, by the Air Force to alert the Japanese people and not to use the second bomb. But it have been released and used, and it was  indeed used as quickly as it was available.

SS: If the Japanese didn’t surrender, was Truman ready to keep dropping A-bombs on Japan?

RR: Truman was shocked by the destructiveness of the weapon and famously told his vice-President: "I want to stop this if we can, I don't like the idea of killing all those kids" - the children, he said. On the other hand, Los-Alamos was prepared, I remember seeing a memo, from Robert Oppenheimer to the general who ran the bomb program, that said: "If we can start making bombs using both uranium and plutonium in the same weapon" - a so-called "composite bomb" - "we could have 6 per month by October". So I think it's clear that at least in terms of having the weapons, that the U.S. would indeed have continued using them. There wasn't much left in Japan to destroy. The next target, for which there was a bomb ready around the 10th of August, was going to be the railroad network in Japan, and that would have completed basically the starvation of the Japanese people.

SS: I also wonder about Truman's thoughts at that moment, because wrote in his diary, when he got the news that the bomb is ready, that “it will be used against military targets, not against women and children”, that the US, as the leader of the free world, can’t do that. How come days later he does exactly that - drops the bomb on women and children, how does someone go from moral high ground to not caring so much? 

RR: The U.S. had made a decision to start bombing cities in 1943, in Europe. It had done so, at least, in part because we had not been able to invade Europe yet, and Stalin was greatly concerned and wasn't at all sure that we were not trying to cause his defeat and destruction. We, on the other hand, were concerned that Stalin might sign a separate peace with the Germans, and complicate things for the U.S.. So, what we had available was bombing, before we could move actual physical goods on to the ground, and when our bombing mechanism turned out not to work for high-precision targets, for hitting a particular factory, we did as the British had done before us: switched to area bombing. The logic was, well, if you're bombing a factory, you're killing the workers inside, so why not go ahead and bomb the neighborhood where they live as well? Then, you'll be sure you kill the workers. But, actually, it was a rationale for the fact that bombs were delivered as far as 5km off target, given the technology of the day. With that move to bombing cities and then with even more deliberate move to firebombing Japanese cities, which were mostly made out of wood and paper, the moral question had already been resolved. I think Truman's note to himself was, probably, self-protective.

SS: In the US, the official rationale for the use of the Bomb on Japan is “it made the Japanese surrender, thus saving a lot of lives”. But what if it wasn’t the bomb that made the Japanese surrender - what if it was the imminent Soviet invasion of Japan instead? 

RR: And, in fact, I think the most recent and reliable scholarship by a Japanese-American scholar who lifted the Russian documents, Japanese documents and American documents, is that, indeed, it was the Russian invasion of Manchuria on the 8th of August... when Stalin got word of the Hiroshima bombing, he was finally convinced that this new famous weapon was not disinformation as he had suspected before, but was, in fact, a real thing, and decided to jump in. His original commitment was August 15th, which would be too late, Russian would not have been in the war at all, in the East. So, he decided to move in more quickly, on the 8th August and that seems to have been the decision that led the Japanese leadership to decide that they had to give up, because now they were faced with fresh armies on two sides, if you will. On the other hand, it was the weapons that led the Japanese Emperor to decide to enter the political system for the Japanese history and insist that the Japanese leadership commit to surrender. So, I think you have to think of it as the bombs were an indirect cause of the actions that led, really led, to the Japanese surrender. I don't think without the bombs you would've had the same scenario.

SS: When Harry Truman told Soviet Leader Joseph Stalin that the US has built the bomb, Stalin simply smiled - and led the Americans to believe he was clueless. Surely Stalin knew that his allies were building the bomb - what was the bluff for then? 

RR: I'm not sure what the bluff was for. The fact is, Stalin had been briefed at great length. There were an enormous number, really, relatively speaking, of Soviet espionage agents involved in the Manhattan project throughout the U.S. and England, and indeed, by then, they had plans for the... at least, a pretty good idea of what the weapons were and how they would work and so forth. That Stalin didn't quite believe all this information is really quite interesting, but he had it at hand, and I think, his shrug about Truman's information, was really just part of making sure Truman didn't understand how much he knew.

SS: So how much, do you think, he knew - like you've said, Soviet intelligence agents were inside the Manhattan project  - how far did they manage to infiltrate the American atomic efforts?

RR: Oh, everything, including the actual physical designs for the weapons themselves was being passed or would shortly be passed by mostly Americans and British compatriots who were involved in the espionage for rather idealistic reasons, and had delivered... I saw a copy of the plans for the bomb that I found in Russia after the collapse of the Soviet Union in 1992, with the actual dimensions of various parts, just before those were withdrawn from circulation by Russian scientists who rightly thought that they shouldn't be out there for anyone to see. So everything was delivered, but again, going back to Adamsky’s comment - if the government didn't trust its scientists, and Stalin didn't trust the scientists, then the conditions weren't right for the full-scale program, and in fact, the Soviet Union did not have a full-scale program until after the war. When Stalin learned of Hiroshima and Nagasaki, he called in the Russian scientists and said: "Give me the bomb, comrades, you have all of the resources of the state at your disposal", and it took those scientists about the same amount of time as it took our scientists to build their first bomb.

SS: I know that Nobel laureate Niels Bohr met with Soviet agents in Copenhagen and revealed some secrets - how did that come about? Weren’t these scientists under tight surveillance?

RR: No, Bohr had gone back to Denmark after the war and surveillance, I think, was not the same there as it might have been in the United States. And, again, Bohr was very careful not to tell the Russians he spoke with anything that was officially secret. He did, inadvertently, give away an important piece of information, which was also given away, inadvertently, in a little book that was published by the Manhattan project, that described in unclassified terms the whole bomb program. But there was an important piece of information about the problem with the certain kind of power reactor that was being used to make plutonium, that had led to having to shut all of those down in the U.S. in the later 1940s for a couple of years until the problem was resolved. That's the information that Bohr shared with the actually Russian espionage people who spoke with him. He was not, however, in any way, a spy, and I think you can see that looking back at his famous meeting with Werner Heisenberg in Copenhagen in the middle of the war when Heisenberg was kind of trying to pry out of him what the Americans were doing, and he was incensed and outraged and their friendship which had been very close, was ruined for the rest of his life.

SS: The physicists in the 1940s tried to behave very independently from the states that helped them to do the research - they had their own ideas about war and peace, even clashed with authorities sometimes. Was their independence real or just an illusion they were afforded to keep them happy?

RR: No, I think their independence was real. They understood, because they were physicists that could do the numbers, they understood just how destructive this new weapon was, and they understood that as soon as another country had them, there would be a potential for horribly destructive war.They hoped, Bohr in particular, that if they could convince the statesmen of what would be the outcome of the world with nuclear weapons, that perhaps they could forestall that development, that if there could be some sort of international agreement, right after the war, perhaps it would be possible not to have an arms race, which is what they anticipated happening. And of course, the statesmen, really, were not prepared to hear that argument, didn't really understand the change of scale of destructiveness that these new weapons would bring. As a result, we now have a kind of stalemate, but we have it with nuclear weapons all over the world, and the risk that follows from all those weapons, rather than before they were built. It might not have been realistic on their part, I think the people could imagine their way forward to such a world without actually building the weapons and experiencing that threat.

SS: Mr. Rhodes, thank you very much for this very interesting interview. We were talking to Richard Rhodes, journalist, historian, author of many books, including the Pulitzer-prize winning  “The Making of the Atomic Bomb”, talking about how the doomsday weapon came into existence 70-odd years ago. That's it for this edition of Sophie&Co, I will see you next time.