The Rest Is Classified - 28. The Spy Who Betrayed Oppenheimer: The Manhattan Project (Ep 2)

Episode Date: March 12, 2025

What makes a man betray his closest friends? How did a German refugee help Stalin build the bomb? And why did British intelligence fail to spot the most dangerous spy in the Manhattan Project? Klaus Fuchs was brilliant, quiet, and unassuming. A physicist at the cutting edge of nuclear science, he worked at the heart of Britain’s secret atomic weapons program before being sent to the United States to join the Manhattan Project. But, all the while, Fuchs was passing the most closely guarded secrets of the West straight to the Soviet Union. Listen as David and Gordon uncover how Fuchs’ communist beliefs and wartime alliances led him to become one of the most infamous spies of the 20th century. ------------------- Order a signed edition of David's latest book, The Seventh Floor, via this link. ------------------- Get our exclusive NordVPN deal here ➼ www.nordvpn.com/restisclassified It’s risk-free with Nord’s 30-day money-back guarantee! Email: [e-mail] Twitter: @triclassified Assistant Producer: Becki Hills Producer: Callum Hill Senior Producer: Dom Johnson Exec Producer: Tony Pastor Learn more about your ad choices. Visit podcastchoices.com/adchoices

I thought you'd be dead by now. Get to the theater and experience the movie audiences are calling. An adrenaline rush of a good time. It's a big screen blast. Find a badass. I know, all right. Nova Kane, now playing. seasoned pro, you can make your investing steps count. And if you're like me and think a TFSA stands for Total Fund Savings Adventure,

maybe reach out to TD Direct Investing. There have been things in my life that I must admit I would do differently. Looking back at those 72 years I've lived I can see all the mistakes I made and those I could have avoided. But I'm deeply convinced that in spite of all the mistakes and the negligent behavior, if the line of your life still took you towards the goal you'd set once and for all, if you were able to reach that goal or at least get closer to it, if going in that direction you did not lose yourself Nor squander your strength commit anything contemptible

Humiliate yourself climb over dead bodies nor harm others to get there if you were able to maintain the moral course Within your soul which in every language is called conscience. You can consider your life a success Welcome to the rest is Classified. I'm Gordon Carrera. And I'm David McCloskey. And that was Klaus Fuchs writing later in his life. That was the first paragraph of Gordon's new book for everyone. My autobiography.

Yeah, of Gordon's autobiography. A life of conscience. No, that was Klaus Fuchs rather than Gordon Carrera, offering some clues on why he made the fateful decision to spy for the Soviet Union. We looked last time at Klaus Fuchs, this fascinating figure who talks there about conscience, who'd grown up in Nazi Germany, who'd fled to Britain, who'd been interned in Canada, who'd been this brilliant mathematician and theoretical physicist, and who'd had a communist past and some communist friends.

We'd left him really just as he was being drawn into what he discovered would be Britain's nuclear program and also meeting with agents of Soviet intelligence. Well, that's right. I think, Gordon, it's probably at this point in the story, helpful to kind of set up a bit of the Soviet intelligence services that Klaus Fuchs is actually going to meet with and start to really work for in the coming years and months. So the Soviet intelligence services in sort of late 30s, early 40s are highly effective in many respects. They've recruited a lot of high profile assets in the 30s and 40s.

You mentioned last time, Kim Philby and the Cambridge Five, that's probably the most notorious example. I mean, there's a lot of, I guess, ideological fellow travelers to Soviet communism in this period, aren't there? And people who kind of see in the Soviet Union, in Russia, a kind of shining example of an anti-capitalist future that's more equal, more just. And this is really the period, which now you sort of think that sounds bonkers, but this is before we knew what we knew about Stalin's purges. And the Soviet intelligence services have, I think, really recruited a lot of ideological spies in this period.

And then it really, I think, built up a very high profile stable of assets across the West. That's right. I think Klaus Fuchs, to some extent like Kim Philby, is one of those people who'd seen those street battles, in Fuchs' case in Berlin and Philby's in Vienna when he was there between communists and fascists and decided they wanted to be on the side of communists. So there was a kind of ideological belief in communism, but also a kind of anti-fascism, which was leading lots of idealistic young people, I think, to the Soviet Union and to

its intelligence agencies, which were at this point the GRU, which think, to the Soviet Union and to its intelligence agencies, which were at this point the GRU, which I guess was the military intelligence agency of the Soviet Union and the NKVD, which we know better as the KGB, which is the civilian foreign intelligence directorate of the Soviet Union. Well, and I think also there's a tendency and there's good reason for this, to just basically call every organ of Soviet intelligence the KGB because they changed pretty consistently throughout this period. It is worth saying that the GRU is separate. And that's the group which Fuchs had originally been put in touch with, was GRU through his

kind of communist contacts in that left-wing hotspot of Hampstead in North London. When we think about Soviet intelligence in this period, and frankly, I think even today, to sort of either take one of two extreme views. One is that they're 12 feet tall. They've recruited tons of high-profile assets. Kind of true in some respects. But then on the other side, Stalin's purges have absolutely wreaked havoc on their capabilities, you know, because these services were not immune from the purges that happened in Moscow in the mid to late

1930s. I mean, the other thing we should note here is that it's a lot easier for the Soviet services to operate in the West than it is for Western services to operate in the very closed Soviet Union. So as a result, the Soviet services, be it predecessors to the KGB, be it the GRU, they're very active in talent spotting in the US and in Western Europe. There's this large pool of potential kind of ideological recruits. The people that we're going to talk about in the story today are these kind of German communist emigres who were in Great Britain, but are kind of ideological fellow travelers

with the Soviet Union. And you know, I think from the Soviet Intel standpoint, in April of 1941, which is when Klaus Fuchs first meets with this GRU officer in London. Now at this meeting, it's kind of unclear if Fuchs really knew who this guy worked for. He's introduced to him as Mr. Johnson, speaks near perfect English, but with this kind of interesting accent. From the Soviet Intel standpoint, I think Fuchs is a very interesting potential target. But he doesn't yet have access to secrets,

does he? I mean, he's a theoretical physicist who's potentially in the swirl to get involved in the British atomic bomb project, but he's not yet involved. He's not yet involved, but he's about to be. And I think it's kind of likely he might have some sense of what's going on because some of his kind of contacts and mentors are deeply involved in this. And I think it's around this time he gets contacted by Rudy Piles, who is another one of these emigre brilliant scientists, and contacts him and is one of his mentors and basically says, would you like to work on a secret project for me? It's probably worth talking about this secret project a little bit because the field of

atomic research at this stage is pretty new. You know, rewind to even 1940, a year earlier, and it's this Rudy Piles guy who's going to become one of Fuchs's mentors who had written a memo that ends up on Churchill's desk that outlines the feasibility of an atomic bomb. And to just paint a picture of how new the science is here, the neutron, Gordon, is discovered only in 1932. So this is like cutting edge stuff, right? We're only a few years away at this point in the story from the neutron even being discovered. And there is a group of German scientists in Britain who had sort of participated in and knew of experiments in which uranium atoms had been split by bombarding them with neutrons, which

in the process released massive amounts of energy. And it's kind of that theoretical concept that's going to serve as the foundation for the work that Fuchs is going to get involved in. And for those not watching on video, Gordon is smiling as I try to describe science behind an atomic bomb. And we've had fights in kind of working through this story over how deep we're going to go here. And this is the point where I'm going to turn it over to Gordon Carrera to describe the science of atomic weaponry.

Take it away, Gordon. I was enjoying it. I thought you did very well splitting the atom. That's all you need to know. To describe the science of atomic weaponry. Take it away, Gordon. No, I was enjoying it. I thought you did very well. Splitting the atom, that's all you need to know. I'll try and do it concisely. The key thing is splitting the atom and it's about using uranium-235, which is fissile, which breaks apart and releases energy.

What they've realized is if you can enrich uranium, so there's more uranium-235, then it becomes possible to build a bomb, but you still need to find a way to weaponize it and to turn it into something that will actually explode. So there's a lot of kind of practical industry, but also theoretical physics required to understand how to do that. That's my explanation, David.

Did that make sense? That's good. Did you know, Gordon, actually, when I was a management consultant, I had to spend months working at a nuclear power plant, and my ability to describe the science never matured beyond what you just described. The key point, though, is at the start of the Second World War, you've got this point at which people have realized it's theoretically possible to build a bomb. But no one knows yet how to actually do it and how to weaponize or how possible it is, or how far other countries might have got on that process. The theoretical physics are directly connecting to the possibility of a weapon here. And it had actually been German scientists in Germany

who prior to the war had first discovered nuclear fission, right, splitting the atom. And within a week of hearing of the discovery, Oppenheimer at his lab in Berkeley had sketched out the basic design for an atomic bomb. Now it's theory at this point, but this direct connection between fission and weaponry is to your point, it's in Germany,

it's in the Soviet Union, it's in the States, and it's in Britain, where you have these scientific communities who are starting to work on and think about how you might translate it into a practical weapon. And of course, the race right at this point in 1941 is with the Nazis. And there's a group in Britain, Fuchs is part of this, and they are concentrating a group to begin working on the British atomic bomb in Birmingham.

And it is a race against the Germans to build this weapon. So Fuchs is being brought into this circle with Rudi Piles, I think is the kind of key figure. And it's interesting as well, because it's a group of largely refugee, expat scientists, a lot of them have got kind of German backgrounds who are working together, who become very close.

I mean, Piles actually hosts Fuchs and to Piles and his wife, he becomes almost like a kind of surrogate son, you know, very, very close, all part of this kind of relatively small group of scientists. And I think at this point as well, Britain has actually got the leading edge on the theoretical side of it, partly thanks to, you know, people like Piles and Fuchs. Actually, when it comes to the theoretical work of building the bomb, Britain is arguably in the lead at this point, and Fuchs is now being brought right into the heart of this program.

Well, and this is the point where a lot of his potential as a Soviet asset translates into practical kind of intelligence, right? Because in May, Fuchs makes the move to Birmingham to join the uranium people, as they're referred to, who are working on atomic research and how to translate these insights into a weapon. Fuchs is again with the Piles. I mean, Rudy Piles' wife actually buys Fuchs's clothes. I mean, he's sort of brought on as this member of the family, and he's beginning to work on the British atomic bomb project. And I think it really does beg this question of how in the world MI5 clears him for this,

because we have this report going back to the mid 30s from Germany that kind of lays out Fuchs' communist connections. And there's also been in the interim, a corroborating report from an MI5 informer who's sort of among the German emigres talking about how Fuchs is a communist. I think he was actually well known in his academic circles, his sympathies for the Soviet Union. You put this guy on the most sensitive project in Great Britain.

It's crazy. Yeah. I mean, in some ways, this is the second kind of failure for MI5. And I think the reason why they fail, it looks like, is partly because it is so secret. Because it looks like MI5 are kind of asked to check whether he can kind of work, but they're not told on what. Because the secrecy around the nuclear weapons program is so intense that they are not told about it at MI5. So as far as they know, this is just someone working who's being asked for a job through the Ministry of Supply or something else to do some work. And so I don't think they quite grasp the fact that he's going to be working on the most secret things. And that's because of the kind of secrecy around it. So he starts working the kind of May, June, July, and actually it's only by October that

he's actually cleared to work, but they do clear him. He's already been working for a few months and he's already actually effectively been given access to the secret. It is another miss basically by MI5. There are these traces around him, but again, they just seem to discount them and consider them almost kind of normal to have some kind of communist contacts. It's also important to note just, I mean, how few people you would have that would be qualified to work on these projects, right? Because within the first week of starting to work on this contract in Birmingham, Fuchs has calculated how the neutrons ejected by

the atoms would scatter when they're hit during the fission reaction. He's theorized a reduction in the amount of uranium 235 required for a sustained reaction. So this is not really widget making, there are very few people who are qualified to do this. And I'm sure at some level, there's a thought that this guy is absolutely brilliant. He's working on a really technical, very sensitive weapons program. And we're willing to take the risk.

So by the summer of 1941, though, I think we're at another real turning point in the story of Klaus Fuchs. So in June, Hitler has invaded the Soviet Union. So Germany and Russia, which had been in this sort of tense kind of non-aggression pact, the Nazis break that, Britain is now a Russian ally and Stalin is pleading for help in Europe. And Churchill, he has kind of got this lofty rhetoric when Britain and Russia joined forces against Germany. He says, we shall give whatever help we can to Russia and the Russian people.

And yet I think from Fuchs' standpoint in Birmingham, he's seeing this work on a super weapon not going to the Soviet Union, right? The Brits are not sharing any of these insights with Russian scientists. And I think it's fair to say, given what's gonna come next, that Fuchs is going to see this lack of British aid to Russia as a kind of twisted desire for both the Soviet and

German armies to destroy each other and it's going to sicken him. It sounds like you're the one being quite sympathetic to Fuchs at this point by saying, well, you know that we're allies. so we were keeping this nuclear development secret from him. I mean, I thought I was the one who was kind of more sympathetic to Fuchs. There's an ambiguity about when he really starts passing secrets to his contacts and whether it's actually might even be before the Nazis invade the Soviet Union, which would be a more controversial thing because then the UK and the Soviet Union weren't allies. But certainly he is motivated by helping the Soviet Union. He now has the access, I guess, to some of the most deepest secrets that the UK has.

And he's just going to pass them on to an ally. Is that okay? Well, no, it's certainly not okay. I mean, I'm merely Gordon trying to understand the mind of the trader and lay it out. I think you're the one who's continually showing sympathies for various son-deprived scientist types who share secrets with the Russians. And you're right though, you know, that it is not exactly clear when in this period in kind of late spring, early summer, Klaus Fuchs makes the decision to kind of take things to the next level and really start to provide the Russians

with practical intelligence. But I think it's fair to say that it's in this period and it probably is sometime around when the Soviet Union is invaded by Nazi Germany that Fuchs starts to see Britain's alliance with Russia as a sort of permission slip to share secrets with Moscow. And the Soviet archives record that Klaus Fuchs had remembered his contact from that April party with the GRU officer, you know, Simon Kramer, who Fuchs knew

as Johnson. And so what happens probably in June of 1941 is that Klaus Fuchs reaches out to a friend who's probably a talent spotter, who passes on a message to the GRU. And the GRU then decides with Fuchs kind of volunteering, raising his hand, and with his new access from his work on Rudy Piles, his team working on the British bomb, the GRU decides to recruit him. And it is a very interesting position, I think, for a spy to be in because, as one of his biographers will state, it's interesting that

Fuchs is actually stealing the secrets, or he's going to be stealing the secrets, but he's also creating them by virtue of his scientific research. So a lot of the really sensitive stuff that he's working on is the basic kind of building blocks of an atomic weapon. So he's actually the one creating the secrets that he's going to give to the Soviet Union. And at this point, he is going to share the fact that Britain has a secret program and that it is building or trying to build an atomic bomb. The program was previously moored, was the kind of committee that was looking after it,

and then it becomes Tube Alloys is the kind of wonderfully low-key code name, isn't it, for the British bomb project. I mean, clearly designed to put anyone off the scent who might be interested in the Tube alloys project, you'd go like, no, I'm not interested in that. But unfortunately, if you're the Soviet Union, you now know, or you're about to know, thanks to Klaus Fuchs, that tube alloys is is Britain trying to build a bomb. It's not as sexy as the Manhattan project, is it? The Manhattan project sounds like a great spy thriller, like tube alloys. I don't know, it sounds like something you'd buy in an aisle at Home Depot.

I don't know if you have those. It is less suspicious, that's true. But by August of 1941, Fuchs now has a GRU code name, Auto, and he is traveling to London to meet with a GRU officer who he calls Alexander. It's this guy, Simon Kramer, who he met in April back at that party in London. They start to meet in the evenings, mostly on weekends, and they'll basically do brush passes

where they'll exchange papers that are sort of wrapped in packing paper or envelopes. They do that at crowded bus stops or on kind of quiet residential streets. And he's handing over material that he's working on, but also probably some of the kind of bigger sexier stuff that Rudy Piles and his team had put together and I think what's really important from the Russian or the Soviet

Intel standpoint is that the big secret he's passing on is that an atomic bomb is both physically possible and it is, I guess you'd say, commercially or industrially feasible. And I think the Russians have their own team of physicists who are starting to look at this too. And I think the fact that the Brits are actually starting to build some of the infrastructure that's going to help with uranium enrichment and the fact that Rudy Piles and his team believe it's possible, that's actually really important to kind of anchor the Russian team in the way forward. They do learn on the Russian side from other spies like John Cairncross, one of the kind

of Cambridge spies, about the existence of the program. But what Fuchs is doing is giving them the details of it, the hard physics and science which the Soviets can then use to shortcut their program. I guess that is the key point. And the Soviets will accelerate what they do because they suddenly understand it's possible. And I love the Soviet name, Enormos, which is their code name for their bomb building project, which gives a sign of just how big a bigger deal they think it is. Well, and some specific things that Fuchs would have provided that were immensely helpful to the Soviets were, well, number one, there's a practical method to sort of concentrate uranium-235. The amount needed for a single bomb was small. That was actually a huge insight because in wartime, getting a massive amount of uranium to enrich could be

technically challenging, right? So if you don't need that much, that's huge. And Fuchs also reports that a contract had been placed to design this kind of diffusion or enrichment plan that would be ready in Britain by the end of the year. The GRU director himself in this period describes Fuchs' intelligence as very important and kind of gives this assessment that the Brits are researching a weapon that would put humanity on the road to hell. So you have this kind of interesting contrast of this massive, really important intelligence

that Fuchs is providing, but we also see in this period that he's kind of an amateur at the spying game, despite his time in the communist underground in Berlin. So he contacts his GRU handler directly by telephone on more than one occasion, which is sort of a breach of proper trade craft. And a memoir actually written by one of his KGB handlers

later on is going to suggest that Klaus Fug showed up at the Soviet embassy to find his handler once and to try to hand deliver 40 pages of notes on the state of the British atomic bomb project. So you have, I think, kind of in this early period, and we'll see how Fuchs develops out of this or sort of matures out of it, the sense that, you know, Fuchs is kind of new to the spy game. He's a theoretical physicist, right?

He hasn't been trained to do this. No, he's following his conscience. And I love this one particular detail, which is that Rudy Piles' wife remembers that sometimes he would kind of look miserable and have this cough. And this cough is really interesting because the cough and the kind of sense of illness seems to appear whenever he's kind of been undertaking some kind of spycraft. And when he's kind of nervous or conflicted, he develops a really bad cough. And you almost feel this is some kind of like indication of the psychological stress he's under.

Because I do think, you know, going into that psychology of the guy, I think it is really interesting because he is someone who is following his conscience. He believes this is the right thing to do to pass these secrets to the Soviet Union. and yet he is also betraying his friends, his colleagues, the people around him, the people who've given him kind of refuge and help and supported him. And I think you can see the kind of psychological toll that that takes occasionally on him between these two different compartments of his life by the kind of cough and the fact he suddenly, they'll notice he looks really miserable and gets kind of ill and starts coughing and that seems to come up again and again when he's under this intense pressure. Well and just to make sure that listeners understand that unlike

Gordon I'm not Klaus Fuchs sympathizer, the betrayal here is really stark isn't it because he's living in Piles's home. Rudy piles, his wife is making meals for him buying his clothes. She's kind of like a surrogate mother. And all the while, class books is betraying all of the research that Rudy piles is leading for the British government. So the level of the betrayal there is very personal. It's not just these kind of faceless superiors that he's maybe, you know,

getting revenge against or taking information from him. This is his, one of his closest friends and the person who's literally put a roof over his head in Birmingham. So anyway, by 1942, his GRU handler, Simon Kramer is recalled back to Russia. And another emigrate communist makes an introduction to a young woman, codename Sonia, who is in reality Colonel Ursula Kuczynski. She is a fanatical communist, a German, a rabid anti-Nazi, and also a resident, and maybe Gordon, you could fill in some of this geography for me,

a resident of great roll right, where according to Ben McIntyre's book about her, her scones were apparently the envy of everyone in the village and she is gonna become Klaus Fuchs's new handler in London. Yeah and Sonya as she's known is a kind of amazing figure whose career in espionage is absolutely remarkable. Kind of all around the world not just in Britain over many years. She's been working for the GRU under really effective cover and manages to elude British intelligence for many years. Beyond her very good scones, I think as a spy, she was first class. I'm sure we might come back to her in a later podcast because I think she'd be worth a story of her own.

It was actually her brother, Jurgen Ko Kaczynski, who'd also known Fuchs as part of that kind of Hampstead crew that we talked about earlier. Although, I mean, Fuchs himself might not have known that they were brother and sister, but yes, they start meeting out on the kind of country roads near Banbury. They never meet for more than about half an hour. They go on walks together. They never go to the same place twice. It's now a pretty good trade craft under Sonya where for those years that they meet, he's able to pass quite a lot of detail to her, which she can then get passed back to the Soviet Union. It all has to go by hand effectively because it's too much detail, all these drawings and

designs that she's passing. It does make me wonder what in the hell was in the water in Germany in the 1920s and 1930s because the number of sort of like extremely ideological lunatic communists and fascists that came out of that place, it's remarkable, isn't it? You have like so much of this story is German on German. It's just, it's remarkable. I mean, all of the top level sort of science in the world was German, right? In this period. And everybody was also extremely ideological.

Where are the practical people in this story, Gorda? They're not here. So between 1941 and 1943, while he's being handled by Sonia, Fuchs is going to transfer almost 600 pages of copied reports, calculations, drawings, diagrams, designs for uranium enrichment, almost a kind of step-by-step guide on the ongoing process of learning how to build a bomb. Almost all of it's going to end up straight on Stalin's desk. And in June of 1942, Klaus Fuchs is going to take a pretty big step.

He signs the Official Secrets Act. And a month later, he becomes a naturalized citizen and swears an oath of allegiance to the crown, just as he is betraying some of its deepest secrets. So maybe, Gordon, there, we take a break and when we come back, we'll see how Class Fuchs winds up burrowing even deeper into the Second World War's most secretive project.

This episode is brought to you by our friends at NordVPN. Now, Gordon, what do you find most useful about Nord? David, one incredibly useful feature I find is the ad blocking software. That stops you being targeted, we all know about that, by intrusive ads whenever you're browsing the internet. Along with the fact Nord blocks unwanted parties tracking me, it makes me feel much safer and confident that my privacy or my privacy is protected online. And you know how much I care about your privacy, Gordon. And you know that one feature from Nord that I really appreciate

is that it also has offline protection, which works even when it is not connected, meaning you can be consistently secure. So to stay secure online, you should take advantage of our exclusive NordVPN discount. All you need to do is go to nordvpn.com slash rest is classified. When you sign up you can receive a bonus four months on top of your plan and there's no risk with Nord's 30-day money back guarantee. The link's also in the episode description box. Welcome back, it's 1943 and Klaus Fuchs has been passing some of the most sensitive secrets of Britain's atomic weapons programme to his Soviet handlers, but he's now going to get the chance to pass

American secrets as well. And that's because the two sides, Britain and America's atomic weapons programme, which have been largely separate, are about to come together. I guess it's a reflection that Britain does have something to offer because it's got the lead, arguably, on the theoretical physics, the kind of work Klaus Fuchs has been doing, but it doesn't have the infrastructure and the resources to actually build the plants and carry out the work to build a bomb. That's something that I think Britain knows America can do. But the relationship between the two countries, it's fair to say, was not altogether easy, even though they're close wartime allies.

When it comes to the nuclear program, I mean, they're both kind of maneuvering around who knows more, who can do more, who's going to benefit after the war. It's not entirely easy, is it? No, it's not. It is a sort of classic mid-century British conundrum, isn't it, Gordon, to have something to offer but none of the resources to actually make it happen. And so, of course, the answer is to send us a communist spy to be embedded in our atomic bomb project. It's really the gift that keeps on giving. That said, by 1943, the strategic situation, as you mentioned, is very different now. America's fully in the war after Pearl Harbor. Both countries have been looking at atomic bombs. But you guys, Gordon, you do have

some big problems. One is it's a massive undertaking to build one. You need a bunch of plants all over the country. It's very capital intensive, which is not something you have a lot of. And that infrastructure, even if you did build it in Britain, would not be safe from the Luftwaffe, right, from German bombing. And so, by the summer of 1943, the US and the UK have signed a top secret agreement called the Quebec Agreement. It was not even made known to the US Congress at that point. And it is a merger, in effect, to build a bomb. But it's a very, I'd say a lopsided merger Gordon, maybe sort of a hostile takeover. The Americans will get to decide

whether and how to share relevant industrial or commercial insights with the Brits. British scientists who work on the program will waive the right to any patents. It's reflective of the fact that we're bigger and have more resources than you do. We basically do all the intellectual work for the relationship and then you get to commercialize it. That's basically what the Quebec agreement seems to me when I look back on it. You take all the benefits of it and Britain gives up all of that, but we give you all our kind of best minds. So basically what you do is you just you send us a bunch of Germans, right? So on December 3rd of 1943, Klaus Fuchs, along with Rudy Piles, who's the leader of the

British A-bomb project and another chemist. They land in Norfolk, Virginia. They take a train to DC. They meet with General Leslie Groves, who will be well known to listeners of this podcast, almost certainly as Matt Damon from Oppenheimer. He is running a project for the Army Corps of Engineers, the Manhattan Engineer District. Its East Coast headquarters is at 270 Broadway in New York City, and it is the Manhattan Engineer District. Its East Coast headquarters is at 270 Broadway in New York City, and it is the Manhattan Project. Now, Fuchs, of course, like any good visitor to New York,

he is gonna stay at a Trump property. He stays at the Barbizon Plaza. Today, it's a Trump Park condominium complex. When Fuchs arrives, it's not clear how long he's going to be in the States for, right? And it becomes clear pretty quickly that he's going to stay for a while. He moves into a more permanent accommodation. And General Leslie Groves, Matt Damon, had been assured that everyone in the British delegation had been cleared by MI5 and the appropriate security organs

in your wonderful United Kingdom, and that there was a special clearance that had been sort of given to everyone who was gonna work in the US. And so, Klaus Fuchs, German communist Soviet asset receives a card with his British affiliation and giving him unfettered access to the Manhattan Project facilities in New York.

Yeah, and I'm afraid this is where it gets really bad for the Brits. There's going to be a big blame game afterwards about how did Fuchs get into this program and Groves is pretty clear that he basically demanded assurances from Britain that all these people had been security cleared and when it all comes out, he lays the blame on Britain. I think that's kind of right. Now, what happens within MI5? And there's some great detail of this in Frank Close's book, Trinity, which has kind of gone

through the MI5 files which have been released. And so there's one MI5 note. Now this isn't passed to the US authorities and it says, Fuchs is rather safer in America than in this country. And for that reason, I am rather in favour of him remaining in America, where he would be away from his English friends. And it goes on to say, it would not be so easy for Fuchs to make contact with communists in America.

And so what the Americans are kind of told is it'll be very hard for him to you know make political contacts but actually what the Brits are going is like he's safer over there than back in Britain because there's so many communists he knows or he appears to be in contact with that it's actually riskier for him to be here in the UK better over there. It's like the Germans exporting Lenin during the revolution. Let's get rid of this guy. What damage could he do in Russia? They actually say, in one MI5 note, it would not appear to be desirable to mention Fuchs' proclivities to the authorities in the USA.

His proclivities, which I think we're talking about his communist proclivities. So there is an explicit kind of decision in MI5, it looks like, to not tell the Americans about some of the kind of questionable contacts he has and to effectively cover it up. So I'm afraid in terms of problems for MI5, that's the big one. Those memos and those notes, which have later been declassified show it was a pretty big screw up, I think, in letting Fuchs go over and in telling General Groves that it was all going to be fine. All was well, yes. It makes the special relationship feel not so special, I think, Gordon, there for a brief moment. Fuchs is in Manhattan. He's doing exciting work, like calculating kind of the effectiveness of components.

But on February 5th of 1944, it's a very wintry Saturday in Manhattan. Fuchs has been in the city for a few months and he, before he departed London, had set up a meet with a new handler. He has actually been handed over from the GRU and his contact with Sonia in London to a new handler, new agent runner in New York, who is going to handle the case going forward. And so Fuchs heads there on this kind of cold Saturday to go meet with his new handler.

Yeah, it's interesting, isn't it? Cause he's being handed over from the GRU to the NKVD, the bit of the KGB. And it looks like, you know, that's partly they've got better networks, but crucially it's because a decision's been taken in the Soviet Union that this is so important to get intelligence

on the Western, the US and the British atomic weapons program that it's been kind of centralized and the NKVD, the kind of the KGB forerunners be told you are in charge, you have primacy over this. That's right. And so Klaus Fuchs heads to a place on Henry Street, it's on the Lower East Side of Manhattan. Again, all the logistics had been arranged in advance. Now, Klaus is so paranoid that he won't even ask strangers on the street for directions. So he takes the subway, comes out, he sees a short, full-faced man in a dark suit and an overcoat.

And the man has a pair of gloves. He's wearing one. He's also carrying a pair and fuchs, in a piece of trade craft here that seems somewhat bizarre, because you might notice it right away, has a book. And he's carrying a green tennis ball. He does not have any of the other things that you need to play a game of tennis, namely the racket.

And he crosses the street toward this man. And the man says, what's the way to Chinatown? And the guy has got a strong Philly accent, which I can't do. I can only do British accents, Gordon, or Edinburgh accents. But this guy from Philly, he goes by Raymond, which is a great, great Philly name. And everything has gone according to plan except that the Philly guy, Raymond, was supposed to carry a single glove, not a great, great Philly name. And everything has gone according to plan except that the Philly guy Raymond was supposed to carry a single glove, not a pair, but it's okay. Contact has been made. And the guy refers to Klaus Fuchs by his code name rest, which is

his kind of KGB code name. Fuchs says, don't call me that. Call me by my name. And Raymond was probably worth setting him up a bit here, he's this kind of sad-eyed timid Philly bachelor named Harry Gold, who's the son of Russian Jewish immigrants. And he's a kind of short overweight guy who's become a true believer communist, his family was emiserated during the Great Depression. He's also got a background in chemical engineering. Now, critically here, I mean, he's not a KGB officer, right?

But he is a kind of courier and leg man for the KGB in the U.S. So Raymond and Fuchs walk together down the street. You know, Raymond's trying to help Klaus relax. They take the subway, then a taxi uptown. They wind up at a restaurant on Third Avenue. Conversation is very sparse. Fuchs is very uncomfortable. They could be spotted, and they're in this restaurant. They're walking around after dinner. Fuchs starts to describe his work, kind of outlines the nature of the Manhattan Project as he understands it. You know,

you've got the sites in Tennessee and in Berkeley and Hanford and this place called Site Y in New Mexico, which is mystery site. And they lay out the tradecraft for future meetings. You know, Fuchs, I think by this point, it's fair to say Gordon has matured a bit in his understanding of proper tradecraft, probably because of the tutelage from Sonya back in London. So Fuchs, I think, is in many respects actually more advanced than Raymond slash Harry Gold. And so Fuchs says, let's not meet at any place twice.

No restaurants. We'll keep it as brief as possible. Fuchs doesn't deliver any material at the first meeting, but soon he's going to start to provide documents, diagrams, sketches, that kind of thing. And the way this works on the KGB side is that after the meetings, pretty much right after, Raymond goes and meets with someone named John, who is not

John, but is in fact a Russian, a KGB officer, who works out of the Russian consulate in New York, and then all the information gets passed on to Moscow. Now, I think it is interesting you mentioned this kind of handover from the GRU to the KGB and it is fascinating now to look back at these memoirs. What does seem apparent is that the GRU did not provide the KGB with a lot of the information that Fuchs had provided in London. And Fuchs is irritated by this because a lot of the information that Fuchs had provided in London. And Fuchs is irritated by this because a lot of the stuff that Harry Gold Raymond is going to ask for,

he had already provided in London, right? And it's coming from the fact that he's getting tasked by a new service. And the KGB was paranoid about the GRU attempting to actually swoop back in and maybe take the case back over. So you kind of get this insight into the inter-service rivalry that I think really plagued the Soviets at this time. Yeah, there was a lot of rivalry and I think there still is between the GRU and the kind of foreign intelligence directorates of the KGB and its predecessors and successors. So yeah, that absolutely makes sense. But it's also, I think that the KGB are slightly more professional, but Harry Gold is a kind of

interesting character because they're also going to use him to contact some other spies that they've got out there in the US, which also adds to the kind of, I think, some of the problems for him and what happens to him later. But at this point, it's working pretty successfully in that they're able to keep meeting, they're able to keep passing secrets during this period when Fuchs is in New York and it's not quite clear where he's going to go to next. Well, he's going to meet with Raymond on a monthly basis while he's in New York. These kind of fleeting encounters in dark, usually down market areas of the city, a colossal handover documents. He'll again, he'll find Raymond to be kind of too casual, kind of sloppy. Klaus will later say that he was irritated because Raymond had a habit of while they

were walking, you'd very obviously look backwards to see if they're being tailed, which is sort of a no-no. And what Klaus is doing in this period is he is exploiting a seemingly sort of mundane loophole in the way that the Manhattan Project is actually managing documents. If listeners will recall our pod a while back on Adolf Tokachev, who was a spy that the CIA ran in Moscow, the way Tokachev got a lot of documents out to be photographed was just kind of exploiting these random banal loopholes in the way documents are managed. Now, Klaus Fuchs is going to do just that

because when he's working inside these Manhattan project facilities, he actually is producing a lot of his calculations, a lot of his material longhand. And then that material is handed over to typists who type it up, give specific numbers to those documents for distribution to specific individuals, but the typist hand the longhand back to Fuchs when he's done with it. So he actually gives these copies to Raymond, his KGB handler. And if Fuchs wasn't the author of something he passed, he would just take the document home, copy it longhand, and then hand that to Raymond and

the KGB. It goes back to the point though, that it's the power of Fuchs being the man originating the secrets, you know, he's not just someone who's having to kind of steal them from a safe when no one's looking there effectively, a lot of them are his documents or ones that he should have access to. And that's why he's able to get such sensitive material and hand it to his contact. In New York, just to set up a bit of, you know, Fuchs the man, I mean, he's basically

living as a recluse, right? I mean, he is in a massive new, at that point, modern city that was not under fear of bombing by the Luftwaffe. And so there's, you know, material plenty, he doesn't really know anyone. The British delegation is small. He's living alone in an apartment on the Upper West Side. And in this period, someone describing his social graces said, in talking, Fuchs' spontaneous emission is very low, but his induced emission is quite satisfactory. So in other words, he only speaks when he's spoken to kind of character and he's having these meetings with Raymond on a monthly basis and kind of probably one of his few social outlets

is meeting with his handler. Now it is a period here where toward, I guess really the middle of 44, his work in New York is actually coming to an end. Like they're kind of running out of useful things for Fuchs to do. And what then all of a sudden becomes clear is that his next assignment is gonna be

either back in England, God help him back to obscurity, or going deeper into the American atom bomb project by going out to this sort of mysterious site, why in New Mexico. And on August 5th of 1944, Fuchs is scheduled to have a meeting with Raymond. He misses the meeting, and then he misses the backup meeting. And he goes missing.

And Raymond and the KGB in August of 1944 have absolutely no idea where in the world is Klaus Fuchs. And so with that, let's leave it for this time with Klaus Fuchs mysteriously disappeared. And next time we can find out where he goes. And he's going into the absolute heart of America's secret nuclear weapons program where he's going to be able to witness that first test of a bomb and provide some of its deepest secrets to the Soviet Union. See you next time. See you next time.