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Michael Joseloff’s Interview

Manhattan Project Locations:

Michael Joseloff is an award-winning television producer and author of the book “Chasing Heisenberg.” In this interview Joseloff discusses the life and career of German physicist Werner Heisenberg and the German atomic bomb program during World War II. He provides an overview of the discovery of nuclear fission and impact in the United States and Germany. Joseloff describes the Alsos Mission, the Manhattan Project’s counterintelligence operation to determine how far along the German atomic bomb project was, and the people involved including Samuel Goudsmit and Boris Pash.

Date of Interview:
February 1, 2018
Location of the Interview:


Cindy Kelly: I’m Cindy Kelly. It is February 1st, 2018. I’m in New York City, and I have with me Michael Joseloff. My first question to him is, please say and spell your name.

Michael Joseloff: Michael Joseloff, M-i-c-h-a-e-l, Joseloff, J-o-s-e-l-o-f-f.

Kelly: Great. Thank you. Well, you’re here today because you’ve written a wonderful book that I just finished, Chasing Heisenberg. Why don’t you tell us something about yourself, what’s your professional background, how did you get interested in this?

Joseloff: I was a producer at the MacNeil Lehrer Newshour in 1993. The executive producer called me and Charles Krause, our foreign affairs correspondent, into his office and he said, “This new book has just come out, an interview with a guy by the name of [Pavel] Sudoplotov.” It was the head of the KGB. He wanted Charles and me to do a story about the book and about the interview.

The most interesting part, at least to us, of the book was, Sudoplotov maintained that Soviet agents had been in touch with [J. Robert] Oppenheimer, and that Oppenheimer had passed secrets to the Soviets. The book, it was based on very flimsy evidence. Of course, it was not true. But in any event, we did a segment about the whole interview with Sudoplotov, and that got me interested in the Manhattan Project. 

I suppose like every other American who’s been through high school, I knew Hiroshima and Nagasaki, Oppenheimer, Los Alamos. What more did you have to know? Once you knew the names and a little bit about what they did, you didn’t need to know anymore. But in doing research for that particular segment, I got into it a little bit more. I realized that there’s a hell of lot more there than my high school education and documentary film watching had told me about.

So I got interested in ’93. I started reading about the bomb, about the Manhattan Project off and on for years with an eye towards someday doing a documentary on the subject. I was taking notes all the time, squirreling away the basic facts that I needed to know, but also stories that I hadn’t heard before, little nuggets of information that I didn’t know. I knew that so much had been written on the subject that, you know, what new could I possibly say about the subject? I tried along the way to interest some of the networks in doing a documentary. I had a lot of information, but couldn’t arouse much interest.

Then one day—got to love the Internet—I was on the Internet looking around and looking for photos of Heisenberg. A photo came up, it was taken in 1939, the University of Michigan, and it showed [Werner] Heisenberg. But, to my surprise—I was surprised he was at Michigan in ’39, number one—but I was shocked to see on his left Enrico Fermi. The two of them are smiling, and looking like best friends there. That really piqued my curiosity. I mean, my lord, these two guys know each other? And they’re together one month before the launch of World War II?

I started doing some digging and I learned that they had met in Germany when Fermi was a student there and Heisenberg was, I think, assistant teacher in Gottingen. As I studied the picture more, there was this guy to the right of Heisenberg, his right, a dapper looking fellow in a white double-breasted suit. His name was Sam Goudsmit. Didn’t mean anything to me, I didn’t know who he was. But I started researching him, and I found out that he was a very close friend of Heisenberg and had an interesting story. All of a sudden, it dawned on me: I’ve got a great story here.

I also learned subsequently that Oppenheimer had been in Germany studying, and had met Heisenberg back in the twenties as well. I’ve got these four men who know each other. They had been friends prior to the war, and after the launch of the war, they become bitter enemies. It was the makings, at least on the surface, of a pretty interesting way into the story of the bomb, especially since Fermi was there. Fermi was the one, in my opinion, who led to the discovery of atomic energy.

We’ve got the lead-up to the discovery of atomic energy with Fermi, as a storywriter here. I’ve got Oppenheimer, who takes us all the way through the development of the atom bomb. Then I’ve got Goudsmit, and he was perhaps the biggest surprise of all. Goudsmit turned out to be—during the war, Fermi, of course, went to work on the Manhattan Project, developing the Allied bomb. Heisenberg went back to Germany, and worked on research for a German atom bomb. This guy over here, Goudsmit, it turned out, became a top intelligence agent at the head of Alsos.

The Alsos Mission, at the end of the war, was to go to Europe to find whatever bomb-making facilities the Germans had, to get hold of their uranium supply, and to capture their lead scientists. Well, their lead scientist, the top—or at least the one that the Americans most feared—was Werner Heisenberg. Of course, Goudsmit had been a very close friend of Werner Heisenberg.

At the end of the story, you’ve got the very close friend searching Europe to find his former friend just struck me as a very poignant and incredibly human story, human angle on an enormous story of the Manhattan Project. That photo led to the book, Chasing Heisenberg: The Race for the Atom Bomb. Long story. 

Kelly:  Great.

Joseloff: As you know, all during my documentary career, especially when I was at MacNeil Lehrer, we’re dealing with the great subjects of our time, war and peace, villages in the West Bank, and that sort of thing. I was always banging and crunching and pushing to make a story, to make the report flow in an interesting fashion.

The beauty of storytelling is, if it’s sort of done well, it just leads you along. You want to know, “What happened next? And what happened after that? And what happened after that?” Whenever I could in my documentary filmmaking, whenever I could find a story, I was halfway home, because the story will want you to move along with it and find out how it ends. That’s why that photo was just so valuable, and why I loved the story with the four characters in it.

Kelly:  Great. So, are you going to tell us the story? 

Joseloff: Well, I start it in 1938, when Heisenberg travels to the United States. That trip by him to the U.S. was kind of a victory lap for him. He had just been through a very difficult period in Germany.

It was ’38. Hitler had passed all manner of laws restricting the rights of Jews. He had kicked all of the Jewish professors out of the universities. Nobody was allowed to teach the theories of Albert Einstein or Niels Bohr, the top of theoretical physics universe. Really, it was debasing. Then they would put in Nazi party hacks who would teach German physics that didn’t include Albert Einstein or Niels Bohr.

When they started going after the professors—Heisenberg had sat by and watched all of the restrictive measures against the Jews, but when they started kicking them out of the universities, that was a bridge too far for Heisenberg. He said, “Enough.” He wrote two articles, one for the SS newspaper and another for a Nazi newspaper. There was this firestorm. Johannes Stark, I think was the name of the Nazi Nobel Prize winner, who took off after Heisenberg for these articles that were pro-Einstein and Bohr and espoused the teaching and the importance of their teaching. That attack on Heisenberg caught the attention of the Nazis. This Nazi Nobel Prize-winning physicist who led the attack really took off after Heisenberg, calling him “a white Jew.”

As a result of that, there was an investigation by Heinrich Himmler and the SS of Heisenberg. This was serious stuff. They bugged his home, and the investigation went on for a year. He could have been put in jail, he could have been executed for supporting the Jews, supporting “Jewish science.”

But fortunately, he had a friend, or at least his father had a friend, in a high place. His father was friends with the father of Heinrich Himmler, the head of the SS. Heisenberg’s mother called up Himmler’s mother and said, mother-to-mother, “My son, he doesn’t deserve this. He’s an honorable man, and you’ve got to do something. Would you please?”

After a year-long investigation, Heinrich Himmler does indeed come to Heisenberg’s defense, and they strike sort of a compromise. They say, “Okay, the professors can teach the work of Einstein and Bohr in their classes. But they can’t name Einstein or Bohr. They can’t say that this work came from Jews.” It had been a very difficult time for Heisenberg during all that period. He also didn’t get the post he wanted, head of one of the university’s physics departments. It had been tough.

At the time, the community of theoretical physicists in the world—because, remember, theoretical physics was a relatively new field. You had Einstein in 1905 come up with his E=mc2 theory, and after that, the world of theoretical physics just exploded. At least, there had been wonderful discoveries after that. 

But it was still a small group that specialized in theoretical physics. That group was pretty much led by Niels Bohr, whose specialty was atomic structure and quantum mechanics. He encouraged all of those who were interested—and I think there were about 100 of them around the world—to share their papers, to publish their papers, to publish their work, good or bad. And to become a real intellectual community around advancing the study of atomic structure. They became sort of a close-knit group, these 100 or so, and there would be conferences when they would come together to share their views, to read their papers, that sort of thing.

Heisenberg had been divorced, in large part, from that community, because of Hitler. He had little contact, certainly with the Americans, and certainly with the British physicists. He was looking forward to his trip to the United States in the summer of ’39, because there would be an opportunity to see old friends, Oppenheimer, Fermi, Goudsmit. And a bunch of others whom he had known— many of them had probably been his students. Edward Teller was one of his graduate students.

He was really looking forward to the trip. This was a victory lap for him because whatever organization it was in the Nazi hierarchy that has to approve foreign trips, after he had Himmler’s approval, nobody’s going to say, “Forget the trip.” It was a victory lap for him.

He came to the United States. He went to Berkeley, and he saw Oppenheimer there. As a matter of fact, he taught his Wednesday seminar. Oppenheimer had met Heisenberg in the mid-twenties when he went to Gottingen, Germany, to study theoretical physics. 

In those days, it’s not like it is today. If you want to study theoretical physics, you got to go to Gottingen, you got to study with Max Born who’s the guy, the guy. If you want to study experimental physics, you go to go to Cambridge and study with so-and-so, he’s the guy. That’s the way it worked back then. All of the distinguished professors probably passed through—at least in the field of theoretical physics—probably passed through Gottingen at one point or another.

When Oppenheimer and Heisenberg met in Gottingen, Oppenheimer was studying there. Heisenberg, I think at that time, was in Copenhagen teaching with Bohr, so he wasn’t on campus. But he came back for visits periodically. Oppenheimer made  it his business to search him out when he did come back, and met him, and they formed a professional relationship. I think both men—I wasn’t there; from my reading—were competitive, and both extremely bright. Neither one liked being told by somebody else—they enjoyed being worshipped, if you will, especially in the German hierarchy. That’s how you dealt with men of the stature of Heisenberg.

Heisenberg won his Nobel Prize in 1933 [misspoke: 1932]. At the age of twenty-six, he was the youngest professor in Germany. Heisenberg was up there with Bohr and Einstein in terms of his brilliance and in terms of his respect around the world. His Uncertainty Principle because a pillar of the theory of quantum mechanics. He was a major figure in the world of theoretical physics at the time.

When Heisenberg came to Berkeley and they met, Oppenheimer’s star had not risen to the heights of Heisenberg’s. Oppenheimer did not like being second-best. I think there was always some jealousy there, Oppenheimer to Heisenberg.

Mind you, when he came to Berkeley, war was in the wind. This was the summer of ’39. Hitler had been so aggressive in gobbling up territory around Germany. There had not been any gunfire yet, but it was clear that that’s where they were heading. When Heisenberg came to the United States, he always carried this cloud of, “What are you going to do when war comes?”

When he came to Berkeley, one of the historians I read talks about him being at Berkeley, and at lunch with Oppenheimer. He was fascinated by the cable cars. The way the tracks cross and the power lines seemed to cross also, the power going to the tracks. That’s all he talked about at lunch. Of course, there is this big elephant in the room, which is the impending war and Nazism, etc. Didn’t go there. 

Oppenheimer says that he didn’t trust—in part because the issue never came up, but also complex reasons, I think the two men’s personalities—he didn’t trust Heisenberg. In fact, when Heisenberg left California and went on to Chicago and gave a lecture about cosmic rays, Oppenheimer was in the audience. Oppenheimer had a different theory than Heisenberg. After the lecture, Oppenheimer sought Heisenberg out, and the two went at it. They yelled at each other, there was an argument that several people have written about. I did a little bit of research there and it turned out, I think, that Oppenheimer was in fact right. His theory was the correct one.

But I think what you had in Berkeley was sort of a professional putting-on-a-good-face, the two of them. I think in Chicago, you got a real sense that they were not friends, and that there was a jealousy there. 

I might backtrack a long way and say that, an interesting story that I learned about Oppenheimer: when Oppenheimer went to Gottingen to study, he came to Gottingen from Cambridge, where he had been studying experimental physics. As I understand, experimental physics means being in a laboratory and setting up machinery or experiments, whatever, and then carefully noting how this experiment went, how that one went.

Oppenheimer found that incredibly boring. He couldn’t stomach doing that. This is a guy who had been a star at Harvard. In fact, he was so depressed by his time at Cambridge that his parents got on a ship and brought Oppenheimer’s then-girlfriend [Inez Pollak] to England in order to deal with him and his depression. 

When he left Cambridge—thrilled to get out of Cambridge—and came to Gottingen, well, there he found his intellectual footing. This kind of theoretical physics was his forte. This is what he was meant to do in life. He shined. He was the sort of student—maybe you’ve had one in a class somewhere—who always wanted to answer the professor’s questions. “Me, me, me.” And wanted to show off, and he did that a lot. He not only did that, but when other students would speak, and he would find their reasoning flawed, he would speak out immediately, and say, “You’re wrong.” You can imagine he didn’t win a lot of friends at Gottingen doing that. 

At one point, the students in his class got together. They signed a petition to the professor saying, “If you don’t keep this guy quiet, we’re going to leave. We’re not going to take the class,” or whatever. It put the professor in an awkward position. What he did—I think it was a brilliant solution—he invited Oppenheimer into his office, with the memo on his desk prominently displayed, and then found a reason to leave the office, believing or perhaps hoping that Oppenheimer might look at it, which he did in fact do. After that, he toned himself down. He listened.

In any event, when Heisenberg came to the United States, everybody—because war was imminent, everybody knew it—all of his American friends in this small community of theoretical physicists urged him to stay in the United States and to teach, and to bring his family, his wife and I don’t know how many kids he had at that point, perhaps five, to bring them all to the United States. I think Heisenberg had an uncle or somebody who lived in the United States. He had offers from all the major universities to come and to teach there.

But he kept saying no. He said, “This Nazism is a passing storm. It’s not going to be here.  When the war is over, they’re going to need people like me to pick up the pieces, to get rid of all the Nazi professors who had been installed in the various universities, to put in some qualified young, physics teachers. To once again bring German physics back to where it once was.”

German physics, German chemistry, German mathematics were bar none the best in the world, recognized worldwide as superior to everybody else. They were absolutely brilliant. But of course, what happened with the rise of the Nazis to power is, as they started kicking out their best professors, a lot of the Jews, the Nazi intellectual community was being debased and the theoretical physics that was being taught in the universities was being debased.

The United States and the world had a lot to fear from Germany, in terms of its intellectual horsepower. They were very strong. But they were also destroying it at the same time, because of the policies. They were losing their best people.

When Heisenberg came to Michigan—Michigan was always both serious academics, but also fun. The one requirement that Heisenberg had for him to come to Michigan was he had to have access to a piano. He was a musician, he loved to play the piano.

He used the opportunity when he came to the United States, he toured the Rockies, he climbed the Rockies, he went to the Grand Canyon. There was always both the serious physics and the fun part. When he came to Michigan, he always stayed with Goudsmit. They had developed a strong friendship, and it was just understood that he would stay there. 

Fermi, that summer of ’39, he was doing research on nuclear fission. But at that point, the United States has not gotten involved in funding our research on nuclear fission. He and Leo Szilard, who worked with him a little bit at Columbia, had to beg and steal and go to benefactors to get money for their research. At that point, the money had run out. Fermi was happy to come to Michigan and to be part of the seminars that took place there.

When Heisenberg left Michigan, he made his way to New York and he boarded a ship for Germany. The ship was virtually empty, or almost. Nobody from the United States is going to Germany at that point. One can imagine he had a lot of time—it was a four or five-day sea voyage—he had a lot of time to wander the deck, you know, look out at the ocean, ponder what was about to come. Again, there was no question. Hell was going to break loose.

The question that he left hanging, Fermi asked him, and I’m sure others asked him, “What are you going to do if Hitler asks you to build a bomb? What are you going to do?” He answered it probably many times. The one I remember, and I think it was to Fermi’s, he said, “Not going happen. It would take much too long to build a bomb. It’s not going to be a factor. It’s not going to be a factor in this war.” He just sort of avoided the question. He didn’t answer the question. He just said, “It’s not going to happen.” But, obviously, the question was left hanging, and that haunted his friends for a long time. What is he going to do?

Interestingly, when he left Michigan and boarded the ship, he took photographs with him of his time in Michigan. One of those photographs will play a part in my story, as we move toward the end. 

We know from his wife, Elisabeth Heisenberg, that he really was looking forward to coming to the United States. Despite the fact that he was not a Nazi—he hated the Nazis, he was very anti-Nazi—and as much as he was anti-Nazi, he was pro-Germany. He was a German nationalist, and he thought that his being part of this community and his affection for this community would win out over the politics, that he would be able to travel the United States and see people, see his old friends, part of this community again, and not be judged by the fact that his passport said “German.” That was a bit naïve, and indeed, later in the story, we will find out that on some issues he was surprisingly naïve.

He got back to Germany. Hitler invaded Poland. He was drafted to work with a group, the War Department, that wanted to develop an atom bomb. He was the theoretician. They started work on that.

Unlike the United States and unlike Oppenheimer, the Germans were not willing to work together. One of the first things they did was, they said, “We got to bring you all together in one spot,” like Los Alamos. “We’ll get everybody working together.

All of the professors: “Uh-uh.” He was head of the department at that university, he was head of the department at that university. They weren’t going to give up their slots. They weren’t going to work under anyone. They all had to maintain their titles, and work separately. That, as we know, proved to be a great problem.

There was another problem, and it has to do with, I guess, the German hierarchical structure and the respect for authority. Nobody would challenge Heisenberg, even when he was off-base. You don’t challenge. Full professor at twenty-six, Nobel Prize, pillar of quantum mechanics, quantum physics, you don’t challenge him. As we learned later in the war, Heisenberg may have been a brilliant theoretician or theoretical physicist, but it appears he was out of his element when it came to building machinery or building a nuclear reactor.

In any event, he gets back there. They are not able to organize the German program the way they want, but they get it going with work being done in different areas. We know what was going on, the British particularly, because the United States was not in the war at that point. But the British knew what was going on. In large part, I think the greatest source of intelligence was the scientists who had escaped Nazism. They came back with all these stories of who was doing what where. We know from the scientists who fled and we know from the previous director of the Kaiser Wilhelm Institute of Physics in Berlin that they had built a lab on the Institute property, a lab called “Virus House.” They called it Virus House because they didn’t want any curiosity seekers poking around there.

Virus House, in fact, was a lab for building a nuclear reactor. We know that because the guy who had been head of the Kaiser Wilhelm Institute [Peter Debye] left. He was given an option: either he had to renounce his Dutch nationality or citizenship and become a German, or what he ended up doing was taking a leave of absence and came to the United States, and never returned. We know what was going on at the Kaiser Wilhelm Institute of Physics, which was really the center for the bomb program at that point, the nascent program at that point. We know because he came to the United States and told us everything that was going on there.

The British, obviously, were very concerned. The British were closer to the line of fire than the Americans were at that point. They were very concerned about the possibility of an atomic bomb. In addition to the scientists who were coming over, the intelligence people—this goes in ’39, ’40 and ’41—were reading the various professional journals, looking for—Heisenberg had published quite a bit before the war. They were looking for articles by Heisenberg, and he wasn’t publishing anymore, which was not a good sign. They figured that he must be busy with something else. They also looked in the university catalogues to see if he was slated to teach any courses anywhere, and he wasn’t slated to teach any courses. Both of those were not good signs.

The British also had a resource. Once the war started, there was friction between the British intelligence and its counterparts in the United States. They would share information, but they might not share all of the information. The British had a guy, his code name was “The Griffin,” his real name was Paul Rosbaud.

Rosbaud was an advisor to the publishing company that published the scientific journals. If you’ve written a paper on whatever and you wanted the world to know about it, you would publish it in this journal, and it would get seen by scientists all around the world. He was an advisor to them. He had his ear to everything that was going on in the world of physics, at least, perhaps other disciplines as well.

He was telling the Brits that, “We know you think Heisenberg is heading up a program to build a bomb,” but by his observations, Heisenberg was pretty much in Berlin. He wasn’t traveling around the country. He had no long unexplained absences, which you would think would be necessary if Germany were building a Los Alamos or an Oak Ridge or a Hanford-type facility. That gave pause to the Brits. 

You have got to remember: intelligence in World War II—at least this kind of scientific intelligence—was not what we have today. You don’t have any satellites overhead that are permanently watching what’s going on. You don’t have the electronic intelligence capabilities that we have today. Intelligence-gathering was always a question of putting in pieces of a puzzle and trying to figure out how they fit, and which ones to assign more importance to than another.

On the one hand, clearly, he wasn’t doing what he had been doing, because he wasn’t teaching, he wasn’t publishing. On the other hand, he was still in Berlin. You would think he would be outside [if he was working on an atomic bomb project]. Once the war started, once the U.S. got in the war, they shared that information with the Allies. But I think it’s perhaps human nature that one intelligence agency always questions the other. Had they known who the spy was, the chief spy, Rosbaud, I think the United States would have paid more attention to what the Brits had to say.

Let me take you back, if I may, to the University of Rome in 1934, with [Enrico] Fermi and his post-graduate students there.

The neutron had just been discovered a few years earlier. Fermi came up with the idea of using the neutron as a kind of ammunition to try to probe the nucleus of the atom. The nucleus is surrounded by an electrical barrier, and other scientists had tried to break through that barrier using positively-charged particles. But the barrier was positively charged, and you needed a lot of energy to break through.

He said, “Well, neutrons don’t have any charge, so maybe they can just sneak right through.” He was right in that. He would bombard atoms with neutrons, and what he was trying to do was turn stuff that wasn’t—aluminum, silver, that sort of lead—stuff that wasn’t radioactive, he was trying to cause it to break into the nucleus, to upset, disturb the protons in there, and to make it start to decay, which is radiation. He was successful in doing that. 

Indeed, stuff, the atoms would start to decay. It might not last for more than a couple of seconds or a minute or so, but it told him when he saw the radioactivity coming off an atom that was not normally radioactive, it told him that, indeed, the neutron had broken into the nucleus and caused it to decay. That was a very important finding.

Had he stopped right there, it still would have been a very important finding. But he didn’t stop there, and as in so much science, it’s just the thing that you don’t plan. On a whim one day—his graduate students were out proctoring exams. He walks into the lab and they had set up an experiment. It was either with aluminum or silver, I forget which.

In any event, they have the source of neutrons over here. They’ve got the silver or aluminum over here. Fermi came up with the idea, “Well, I’m just going to—.“ They had a piece of lead or something in-between the two, they were trying that. And he said, “Nah, I’m going to—.” There was some paraffin nearby, some wax, and he said, “I’m going to put the wax in between and see what happens.” 

He puts the wax in between, and then he picks up his sample to see whether or not it’s turned radioactive. He couldn’t keep the Geiger counter in proximity to the test, the experiment, because there are too many neutrons flying around and it might corrupt the results. The Geiger counter had to be all the way down at the end of the hall.

What you saw all that summer and fall that they were working on this experiment was, he grabbed the piece of metal that had been irradiated, runs down the hall, puts it in front of the Geiger counter. “Oh my God.” They had gotten a radioactive reading off it before, they knew that the neutrons were entering the nucleus and causing it to decay. But this was considerably more, dramatically more radioactivity coming off of either the silver or aluminum than he had ever seen before. That was astounding. He couldn’t, couldn’t understand why. A piece of paraffin? A piece of wax between the source?

His graduate students come back from proctoring the exams, and he tells them what’s happened. They try to repeat the thing, and, “My lord!” It happens again, and it happens not just with silver, but with other [elements]. Somehow, for some reason they didn’t understand, putting this piece of wax between the neutron source and the piece of metal that you were irradiating caused it to become much more radioactive, which meant more neutrons were entering the nucleus, much more radioactive than it had previously. That finding was part of the reason why he won the Nobel Prize in 1938.

I want to take you back farther, if I may. After [Albert] Einstein came up with his theory of E=mc2, nothing much happened with that theory in 1905. It was great for selling newspapers. I have here, “Tinkering with Angry Atoms May Blow Up the Earth.” You could sell a lot of papers with a headline like that, and there were others. It was wonderful sort of science fiction, a great way to sell.

H.G. Wells wrote his book, whose title will come to me later [The World Set Free]. He envisioned in 1959, the year of this global conflagration of atomic bombs, all countries being armed with atomic bombs and firing them at each other. He talks about: people were starving, because the farms were all radioactive. He talks about credit in the world, everything was destroyed, because the institutions that ran society were all destroyed. That was his vision for ’59. That’s where the theory of E=mc2 pretty much stayed until the mid-to-late 1930s. It was great for selling newspapers and books. But nobody, to my knowledge, had really advanced that theory. 

Fermi, when he broke into nature’s inner sanctum, if you will, the interior of the nucleus, he began chipping away at the storehouse of atomic energy. He opened the door. He was the one who found the key to getting into the nucleus that others then used to access atomic energy. That’s why I always felt that, in writing this book, that Fermi was extremely important, and nobody quite understood his importance.

There’s only one atom [isotope] in uranium that will fission. As you know, it’s U-235. They didn’t know it at the time, but what was happening when he used fast neutrons, for every U-235 atom in uranium, there are 139 other atoms that love to gobble up fast neutrons. Nature put them there to gobble up fast neutrons. When you fired fast-moving neutrons at the nucleus of an atom, all of those sentries, if you will, those 139 for every U-235 storehouse made certain that a large majority of them didn’t make it to where they were trying to go. It’s like a baseball player who can hit a fast ball, but can’t hit a slow curve.

Nature, when it came up with its massive plan for protecting atomic energy from curious scientists, it made a mistake. It equipped all of the other atoms to be able to grab hold of and to absorb fast-moving neutrons. But it didn’t equip them to deal with slow-moving, slowpoke, tortoise-wins-the-race neutrons. The slow-moving neutrons were able to sneak through, get into the atom, into the nucleus, and cause it to decay.

That technique was the technique—slow-moving neutrons—that [Otto] Hahn and [Fritz] Strassmann later used in December of ’38, I think, to discover atomic energy. When the slow-moving neutrons entered the nucleus of the U-235 atom, it split, it gave off two neutrons, and it gave off a burst of energy. Hahn and Strassmann, with the help of Lise Meitner, discovered that, and that’s how they discovered atomic energy.

I believe that Fermi actually discovered atomic energy, but he didn’t know it. I believe that the [Frédéric and Irene] Joliot-Curies in Paris actually discovered atomic energy, but didn’t know it. And Glenn Seaborg in Berkeley discovered atomic energy, but didn’t know it.

Dick Rhodes has a wonderful quote from Seaborg. He told Rhodes that when the announcement came that atomic energy had been discovered, he said he was in a blue funk for weeks after that, because he had seen the evidence, but he didn’t know what he was looking at. He didn’t have a Lise Meitner there to tell him, “This is what you’re looking at.” It was Fermi who opened that door and gave them the tools they needed to get into the atom and to release atomic energy.

Now, if I can jump forward. The important thing, extremely important thing, here is slow neutrons. Fast neutrons, at this point in the story, are just worthless. You needed to slow down the neutrons in order to get them into the nucleus, and get them past all those other atoms that wanted to gobble up fast neutrons. What do you use to do that?

When Fermi gets to the United States, he starts working and he tries all different techniques. Ultimately, he and Leo Szilard decide that graphite—Fermi had used wax in Rome—they decide that graphite is a good basically obstacle course, if you will, that you can put between the neutron source and whatever you want to irradiate.

There was a problem with the graphite. It’s got impurities in it, and the impurities were absorbing neutrons. That was a problem. But Szilard goes to the National Carbon Company and says, “This stuff isn’t good enough. We need it more pure.” The National Carbon Company, indeed, does produce a purer type of graphite. They try it in their experiments and sure enough, it works. 

They eventually design a reactor. They put the uranium in canisters, they embed the canisters, and then they have graphite between the different canisters of uranium, so that any neutrons coming off the uranium will have to go through the graphite. The carbon atoms in the graphite serve as an obstacle course, slowing down the neutrons so when they get to the next canister full of uranium, they will be the right speed in order to make their way into the nucleus there.

Heisenberg, off in Germany, knows he has a similar problem. He’s got to come up with what they call a moderator, something that will slow down the neutrons. They try graphite, just as Fermi did. But their graphite has impurities in it, and the graphite ends up absorbing a lot of the neutrons. They decide it won’t work.

They decide that they’re going to use another chemical, a liquid chemical, something called heavy water. They’re going to try that to see if that will work, as this obstacle course to slow down the neutrons. Indeed, it does work.

But graphite was readily available and relatively cheap. There wasn’t a problem getting hold of it. Heavy water was not available at all, and was very expensive. The only factory in the world that produced heavy water was this factory in Norway, the Norsk Hydro factory. They were producing fertilizer, and it just happened that heavy water was a by-product of making fertilizer. 

The Norsk Hydro plant, it was sort of chiseled into a mountainside and above it, you had a lake, and you had water from the lake spilling down into a gorge. They were able to harness the energy of that, the hydro power. They had a limitless, unlimited source of energy and they could make fertilizer and they could make the heavy water.

The Germans tried to buy that heavy water before the war, and the Norwegians wouldn’t sell it to them. But when the Germans occupied Norway, the Norwegians had no resource. They had to not just sell it, but the Nazis made certain that they kept boosting the production of heavy water because it was a major component of a reactor that would produce a sustained chain reaction. They had to have it.

The United States had the graphite. Germany put all of its money, all of its cards, on this Norwegian plant. As we know later, it turned out to be a colossal blunder on Heisenberg’s part and the Germans’ part.

That plant—starting, I think, in November of ’42—it was attacked four different times. In a fifteen-month period, it was attacked four times by the Allies. First time was tragic. They sent two bombers, which were towing wooden gliders, and in the gliders, they had commando squads. Unfortunately, the gliders were attached to the bombers by a rope. The cold weather, the moisture caused the rope to freeze, it snapped. The gliders crashed. Many of the commandos in the gliders were killed. One of the bombers also crashed. The Germans found the survivors and killed them. It was not a happy experience.

The second time they went in, they parachuted in. They were fortunate that one of the managers, the designers of the plant, had escaped to England. He came to England with blueprints of the whole Norsk Hydro operation. They had saboteurs in England, who were training on how to best plant the explosives to decommission, to knock out the plant. They were able to parachute the men. A tremendous feat of mountaineering: they went down into the gorge, across the frozen gorge, up the other side, snuck in some sort of passage that they knew about, and set off the explosives. They put the plant out of operation for six months or so, but only six months. The damn thing was back in operation again.

The next try, they sent—at this point, the United States was in the war. This was no longer a British RAF operation, these were American planes. I think they sent 200 planes to this plant to bomb it. They dropped 700 bombs on the plant. But unfortunately, the plant, as I said, was chiseled in the side of a mountain, and it was a very difficult target to hit. Unfortunately, they ended up killing twenty-one Norwegians, and not doing very significant damage to the plant.

On the fourth try, as you can imagine, at this point the Germans are fortifying the plant. They’ve got machine gun nests, they’ve got landmines, they’ve got soldiers patrolling the area. The only option at this point—they know the heavy water is being transported to Germany. Part of the journey is across a lake. What they do is they take the heavy water, the thirty-nine barrels of it, put it on a train. They take the train to the head of the lake, the train goes onto the ferry, the ferry takes it across the lake and it goes on eventually to Germany.

What the Norwegian resistance did was, they sabotaged the ferry. They put explosives in front of the ferry that were timed to go off when the ferry hit the deepest part of the lake. They did go off, and I think fifty-three people were killed. It’s unfortunate, it’s terrible, a lot of innocent people lost their lives because of this. 

The dependence on the Norsk Hydro plant turned out to be a real weak link in the German supply chain, and they paid for it. There was never enough heavy water for all the experiments that they wanted to do.

Joseloff: [J. Robert] Oppenheimer was brilliant. It was one of the rare times that General [Leslie] Groves retreated. Oppenheimer said, “We got bring everybody together in Los Alamos.”

And Groves said, “Uh-uh, compartmentalization, we can’t do that.” 

Oppenheimer insisted, “I want everybody to know what’s going on here. We want the best minds all working on the problems.”

He won the day there. The Germans didn’t do that. The Germans, they had everybody working separately.

The Alsos mission was set up by General Groves, and the purpose was: 1) to locate the German bomb-making facilities, 2) to get hold of the German supply of uranium, and 3) they were very afraid that the Soviets would get hold of the German bomb-makers, the German scientists, so to capture the German scientists and make sure they didn’t fall into Soviet hands. They set up this—it was called the Alsos Mission to accomplish those goals.

It turns out that the man asked to head the scientific group in the Alsos Mission was Heisenberg’s old friend, Sam Goudsmit. He knew all the players. They had all come to Michigan, and he knew them, again, because of this small community. He also had an interest in forensics. He studied forensics in college.

The military head of the operation was a guy who was head of counterintelligence at Los Alamos. He was constantly after Oppenheimer. Boris T. Pash, Colonel Boris T. Pash, was in charge of counterespionage, counterintelligence at Los Alamos. He always had his eye on Oppenheimer and made Oppenheimer’s life difficult there.

In any event, I think November ’44 [misspoke: August ‘44], Paris is liberated. The Alsos Mission goes into Paris. Their first stop when they get there, they go to the lab that’s run by the Joliot-Curies, who had struck a deal with the Germans during the war. The Germans didn’t have a cyclotron, which was essential to taking the measurements that you needed to build a bomb. Goudsmit figured if anybody knew what was going on, they would. In fact, they didn’t, they weren’t very helpful. That was a false start.

They then went on to look at German chemical and electronics firms in Paris to look through their inventory, look through their guest logs, look at their phone logs, see who had come and gone. That didn’t produce anything either.   

Hunting through the guest logs and going to the German electronics companies and chemical companies didn’t work.

But they did find something curious. A guy who worked for the Auer, A-U-E-R Chemical Company, a large German company, a guy by the name of Herr Peterson. They found in his notes that he had shipped large quantities of thorium, a radioactive substance, to Berlin, and he did it just before the Allied troops entered Paris. That was suspicious, because thorium could be used to make an atom bomb. Goudsmit’s antennae go up immediately.

They eventually tracked down Herr Peterson, capture him, bring him back to Paris. He says, “I don’t know what you’re talking about. There’s no bomb here.” But in his luggage, they find a hotel bill for the town of Hechingen. Allied intelligence knew that the Germans had moved—the Americans had bombed the facilities that they knew of, the universities that they knew of that were involved in bomb-making in Germany. They took their whole operation underground.

They found this hotel bill in his suitcase from Hechingen. Goudsmit knew that this was suspected to be the city, the town where Heisenberg had moved his operation to. The name immediately came back to him.

He had this thorium, large shipments of thorium, being sent to Berlin. He had this connection to Hechingen, and he had this connection to Auer, this enormous German chemical company. Goudsmit said, “This is it. We’re onto it. We’ve got to get to Hechingen. We’re going to find what we’re looking for.” “Tight case” was, what he called it.

Unfortunately, it wasn’t a tight case. It turned out that Peterson’s mother lived in Hechingen, that’s why he went there, to see her. The reason they were shipping all the thorium to Berlin was Armed Forces Radio ran the Bob Hope Pepsodent Hour on the radio. The Pepsodent gave you a brighter smile because it had irium in it. Nobody knows what “irium” is, but that was the advertising claim. “Pepsodent with irium, a brighter, whiter smile.” It boosted their sales.

Well, no fool, Auer, they said, “Well, hell, if irium can boost the sales of Pepsodent, then we’re going to take all this thorium and send it to Berlin. After the war, we’re going to make toothpaste, and we’re going to boost sales with thorium.” That was the reason why all of the thorium went to Berlin. It was obviously a dead end.

But they did find a catalogue when they were in Paris for Strasbourg University, and that, indeed, looked promising, because several German physicists were working in Strasbourg and Goudsmit was very eager to get there and to interrogate them. They had to wait for the French and for the Allied Forces to move the Germans out of Strasbourg, and they did.

When they got there, they immediately went to the laboratories and combed through all of the papers. Goudsmit was shocked—there was no level of security. They had notes from secret meetings. They even had stationery. There was a stationery there with Heisenberg’s name on it, his telephone number and his address. Anybody who wanted to go see him or bomb him or whatever, all they had to do is look on the stationery and there it was. There were tons of paper. He would read through all of this paper at night by candlelight, because the Germans were still bombing Strasbourg.

Goudsmit eventually became convinced that they weren’t building a bomb. He didn’t find any evidence of an Oak Ridge or a Hanford or a Los Alamos. It just wasn’t there. He was satisfied that they hadn’t built a bomb.

Strasbourg turned out to be a very wrenching experience for Goudsmit. Among the papers, he found a letter to a Nazi colonel, a general or whatever, in charge of one of the camps. This biologist, German biologist, was complaining that in the last group of 100 Jewish prisoners that they had sent him, eighteen died along the way and only twelve were suitable for the tuberculosis and influenza and vaccine experiments that he was running.

Goudsmit read that. Goudsmit’s parents had been seized earlier in the war in Holland, and he was told they had been sent off to a Nazi death camp. This really, really registered with Goudsmit. By chance, he was billeted in the apartment of the biologist who ran these terrible experiments. He’s in the bedroom of the guy’s son, and here’s all his Hitler Youth [items] and his toy trains and everything. Goudsmit is a genial, nice guy. He was not cut out for this sort of thing.

Then in the morning, when he leaves his apartment and goes to the Alsos headquarters, he’s got to step over a bunch of weary soldiers, crying, trembling, who are suffering from shellshock. It became too much for Goudsmit. He went back to the apartment. He broke down, he had a nervous breakdown. They sent him back to Ann Arbor for some R&R.

He eventually comes back. In April and May, they finally begin to track down, hone in on Heisenberg. They go to Haigerloch, I think was the name of the town. The people in the town say, “No, no, no, there’s no bomb work going on here. But see up there, in that cliff up there, there’s an entrance. If you go in there, they built a pit in there. There might be something you want to see in there.” They’re able to find someone who’s got a key, they open the door to there.

Indeed, they find in this ten-foot-wide pit, they find a metal vessel. That vessel is Heisenberg’s nuclear reactor. It’s all he has to show for his research on nuclear reactors. Hanging above the vessel, the lid to the vessel is a metal lid, and hanging from that are 600 cubes of uranium. What they would do is, they would lower the lid onto the cylinder, secure it. They would pump heavy water into the cylinder, and then test to see whether or not it was producing neutrons, whether or not it was approaching a chain reaction. They never sustained a chain reaction.

The entire American bomb program was designed because FDR and everybody else thought the Germans were building a bomb, and there was no way to defend against it. The only way to defend against it was to build a nuclear bomb of their own. There was no bunker that would protect you from an atomic bomb. That was the whole reason why the Allies built the bomb. It basically started out as a defensive measure, a countermeasure. That was quite a shock.

The military forces of Alsos move on to Hechingen, and they go into Heisenberg’s lab there. Goudsmit isn’t with them at that point, but they go in and they’re looking around. They find Heisenberg’s office, they find his desk. On the desk is a photograph, and the photograph, it turns out, was taken at the University of Michigan in the summer of 1939. In the photograph is Werner Heisenberg and his good friend, Sam Goudsmit.

One of the officers who was with them at the time was shocked, believing that, “My God, he’s a double agent.” Well, the other people in Alsos, of course, knew of the history, so they ribbed Goudsmit about that all during the war.

Eventually, Boris Pash makes his way 150 miles from there, and he finds Heisenberg. Heisenberg is in the cabin that he bought for his family in the mountains, hoping they would survive the war and be fine. Pash arrives, the soldiers arrive, and Heisenberg is sitting on the deck. He says, in essence, “I’ve been waiting for you.”

They find another photo, by the way, of Goudsmit and Heisenberg there. This one is taken from Göttingen, when they were both there studying.

They take Heisenberg to the office, where Goudsmit is located. Goudsmit is now in charge of sort of interviewing all of the scientists, deciding which ones are important enough to be spirited out of Germany and taken away, so that the Soviets can’t nab them. There’s no way that they would allow Heisenberg to stay in Germany. He was definitely going to have to be removed from the county. 

He comes in, and the two men are there in the office. It’s perhaps human nature, I mean, so much had happened between the time they last saw each other in Michigan. There was almost too much to say. 

Goudsmit asked Heisenberg, as he had in 1939, he said, “Would you like to come to the United States?”

Heisenberg, again said, “No, I’ll be needed in Germany.” Goudsmit thought that was terribly arrogant of him to think that he was that important, that the entire university structure of Germany depended upon his being there.

Then Heisenberg asked Goudsmit, he said, “Can I show you the work we had done on the nuclear reactor?” He’s a German. Of course, he believed that they were far ahead of the Americans in developing a bomb. This was one of the reasons that Heisenberg wanted to build the bomb, was he knew that Germany was going to lose the war and he wanted to use it as a bargaining chip to win favorable treatment from the Allies.

Goudsmit thanks him, and he says, “It’s all right,” leaving him with the impression that the United States didn’t have a bomb or weren’t building a bomb, and didn’t much care to see what he had done.

Interestingly enough, and Goudsmit wrote maybe half a page—that’s all—on their meeting. He basically concluded, “He was strongly anti-Nazi, which we always knew, and still a very strong German nationalist.”

Heisenberg, interestingly, found a letter that he had written to his wife and never mailed, and the letter said what a wonderful meeting it was with Goudsmit, it was like the six years had never happened, that he was so pleased that the meeting went so well. Again, there’s a kind of naiveté about Heisenberg that surprises me.

Then the next step is: they take all of the Germans, or the top Germans, to Farm Hall, a safe house in England, to let them stay there the rest of—well, the war is pretty much over, but stay there until they sort things out and figure out what they’re going to do with them. Because, again, they don’t want the Soviets to get hold of them. It’s a rather cushy place. They got gardens and they got POWs who were tending the gardens, and they got tennis courts, and they got a piano for Heisenberg to play.

They have microphones in every room. The Germans didn’t know that. They were totally bugged when the BBC announces on August 6 the bombing of Hiroshima. Otto Hahn, who discovered atomic energy, learns about it first. Hahn is suicidal. He didn’t want what he discovered [nuclear fission] to cause this. In any event, they come out. They had seen the 7:00 news, and then everybody goes to dinner. They tell them at the table, at the dinner table, what Hahn has learned. Then they go and watch the 9:00, or watch—they listened to the 9:00 news. It says, “Hiroshima bombed by an atomic bomb.”

Heisenberg is incredulous. One, he feels humiliated, because Goudsmit has led him down the garden path, believing that the U.S. wasn’t working on a bomb. Then his colleagues ask him, “Well, how much uranium would you need to build a bomb?” I think at this point, they knew about U-235.

Heisenberg says, “Frankly, I never worked it out. I never thought you could separate U-235 from uranium. I never did the math.” That was the first step in building a bomb. You had to know how much U-235 or plutonium you needed for critical mass. That’s where it started. Heisenberg had never even gotten to the starting point.

After Nagasaki, they put out this statement covering their asses. They say, “While the Americans were working on a lethal weapon, we were working on a uranium machine, a nuclear reactor that would benefit mankind, an engine that would make use of this source.” It’s not entirely true. If they could have gotten that engine working, they would have been producing plutonium. That’s the story that they tried spinning at the end of the war.

At the end of the war, Heisenberg was a sort of a sorry character. He was very depressed after the war. The narrative on Heisenberg became that he was either a second-rate engineer because he couldn’t build a reactor, or he was a saboteur, he deliberately sabotaged the German program. All of the newspaper pieces and the books that were written had him on one end of the spectrum. He was very frustrated that he couldn’t change the narrative. For the last ten years of his life, he refused to talk about the war, because he couldn’t get his—as we would say today—his message out.

One other piece of the puzzle I should mention: Hitler thought, you know, blitzkrieg had worked so well in Europe. He just breezed through Poland and France. France fell in thirty-five days, the largest army in Europe. They thought it would be a fast war.

Then they attacked the Soviet Union, and they got bogged down outside of Paris [misspoke: Moscow]. They weren’t equipped for a winter war, they didn’t have gloves, they didn’t have boots, coats. And, it became a war of attrition. At that point, they realized that, “We don’t have the luxury”—Hitler all during the war had been talking about these “Wunderwaffen,” these great miracle weapons that he was producing. He did produce, you know, the V-1, V-2 rockets. He did produce a jet engine, and I think a proximity, what do you call them, not bomb, but a proximity—

Kelly:  Fuse.

Joseloff: —Fuse, which were pretty revolutionary. But it turns out that an atom bomb was never on their wish list.

In 1942, I think June 4, 1942, Albert Speer, who was head of war development, called everybody together and said—they had all agreed, “Listen, this is going to be a war of attrition. We can’t afford to spend money on these projects that aren’t going to reach fruition during the war and not going to help us during the war. We’ve got to get rid of what we don’t need.”

They bring in Heisenberg, they bring in everybody else to make their presentations. Heisenberg says, “Just had great success. Got at long last a little bit of a chain reaction in a nuclear reactor. Great promise for building weapons that are a million times more powerful than anything we have.”

Speer says, “Fantastic. I’ll give you three million Reichsmarks to build it.”

Heisenberg says, “Ahh, I don’t want three million Reichsmarks. Give me 350,000.”

He says, “What? I’ll give you the three million and I’ll bring 200 soldiers who are now fighting the war but have science backgrounds, I’ll bring them back. They’ll work with you and we’ll get this.”

Not interested. He says, “I want 350,000 Reichsmarks, and I want to build a uranium engine.” Says, “Uranium engine, you can use it to power submarines, we can use it for all sorts of energy sources.” He said, “The problems of building a bomb are just monumental. We could never do it. It would be a waste of money. Let’s build the uranium engine.”

He had an ulterior motive. All during his career, his desire was to prove to the Nazis, prove to the government, that theoretical physics had a place in the world, that it could be beneficial to the world. All he wanted to do was build a nuclear reactor, to prove that theoretical physics could build a revolutionary power source. That’s why he wanted the 350,000. 

He never reached that goal. Yet the fear of Heisenberg reaching that goal, the fear of the German war machine, the fear of all of the brilliant scientists in Germany forced the United States and the Allies to build the bomb themselves. That’s why we’re where we are.

After Heisenberg and Goudsmit met, the Allies went into the camps and they saw the horror, the terror, awful atrocities. It was then that Goudsmit learned that, indeed, his parents had been killed. They had been murdered on his father’s 70th birthday, as a matter of fact.

Goudsmit also learned that Heisenberg had had an opportunity to save his parents. He learned that Heisenberg had an opportunity to save his parents, that a mutual friend had written Heisenberg, saying, “Goudsmit’s parents have just been arrested by the SS. They’re about to be sent off in trains to Auschwitz. Can’t you do something, please?”  

Heisenberg writes back a letter. He says to the authorities in Holland. He says, “Goudsmit has always been a good friend of the German people. I would be very unhappy if they experience any difficulties in Holland, if the Goudsmit parents experienced any difficulties.” That was the language he used. 

Goudsmit always blamed Heisenberg for not doing enough to save his parents. It was not until the day that he wrote the obituary, that Goudsmit wrote the obituary for Heisenberg, that he finally said, “I think we have to say that none of us in those circumstances could have done anything more than Heisenberg did to try to save my parents.”

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