Latest / The History of Germany: Kingdoms, War, and Rebuilding Europe — Fexingo History / Germany's Nuclear Ambitions: The Uranium Project and Kaiser Wilhelm
Transcript
- Lucas: So we've covered a lot of ground — from the Investiture Controversy and the Reformation, right through to the Stasi and the Berlin Airlift. But there's one topic that we've only touched in passing: the German nuclear program during World War II. I'm talking about the Uranprojekt — the attempt to build an atomic bomb for Hitler. Luna: I've heard the myth that German scientists were close to the bomb, but that they deliberately stalled because they were morally opposed. How much of that is true? Lucas: That's a great question, and it's one of those cases where history is more complicated than the popular story. To understand it, we have to go back to 1938, when two German chemists, Otto Hahn and Fritz Strassmann, working at the Kaiser Wilhelm Institute for Chemistry in Berlin, discovered nuclear fission. They fired neutrons at uranium atoms and found that the nucleus split, releasing enormous energy. Luna: So the Nazis actually had the world's first nuclear scientists. Lucas: They did. Hahn and Strassmann were top-tier scientists, but they were not Nazis. Hahn especially was an anti-Nazi. Their colleague Lise Meitner, a Jewish physicist who had collaborated with Hahn for decades, had fled Germany that same year. She escaped to Sweden, and together with her nephew Otto Frisch, she interpreted the experimental results correctly — they named it 'fission' and calculated that it could theoretically sustain a chain reaction. Lucas: Word quickly spread. The German War Office set up a research program, the Uranverein or Uranium Club, under the supervision of the Army Ordnance Office. They recruited top physicists, including Werner Heisenberg, who was already famous for his Uncertainty Principle. Luna: Heisenberg — the one with the famous principle. Did he want to build a bomb? Lucas: That's the million-dollar question. Heisenberg was a brilliant theoretical physicist, but he was also a German nationalist. He stayed in Germany during the war, which earned him suspicion from the Allies. But his actions are ambiguous. In the early years, he seemed to believe that the bomb was feasible and that Germany could win with it. But by 1942, the program had shifted away from a weapon toward building a nuclear reactor — a Uranmaschine that could produce energy, not a bomb. Lucas: Part of that was technical. They needed heavy water, Schweres Wasser, as a moderator to slow down neutrons. Regular water would absorb them. The only major source of heavy water was the Vemork hydroelectric plant in occupied Norway. Luna: Vemork — that's where the Allies launched sabotage missions, right? Lucas: Exactly. The British SOE and Norwegian commandos conducted a series of operations to destroy the heavy water production. The most famous was Operation Gunnerside in 1943, where a small team skied into the gorge, climbed down a frozen ravine, and blew up the electrolysis chambers. They crippled production. Lucas: But even before that, the German program had stalled. There were organizational rivalries — the Army, the SS, the civilian Kaiser Wilhelm Society all competed. Heisenberg was a theoretician, not a weapons engineer. By 1942, when Albert Einstein’s letter to Roosevelt had already triggered the Manhattan Project, the Germans had concluded that a bomb was years away. Luna: So they never really came close? Lucas: No, not to a deliverable bomb. But they did build a prototype reactor — the B-VIII pile at Haigerloch in southern Germany. In early 1945, Heisenberg and his team actually achieved a brief chain reaction, but they didn't have enough uranium or heavy water to sustain it. The reactor went critical for a few minutes before it shut down. Lucas: Then there's the Farm Hall episode — that's the English country house where the British interned ten German scientists after the war, including Hahn and Heisenberg. They bugged the rooms. When the scientists heard the news of Hiroshima on August 6, 1945, their reactions were recorded. Heisenberg seemed stunned — he thought the Allies were years ahead. Hahn was horrified that his discovery had been used for a bomb. Luna: There's that famous quote — Heisenberg supposedly said 'I didn't think it would be possible for another twenty years.' Lucas: That's right. And that's where the 'moral resistance' myth gets complicated. Some historians argue Heisenberg never fully understood the physics of an implosion-type bomb. Others claim he knew but deliberately misled the Nazis. The transcripts show he was rattled, and he quickly tried to claim that German scientists had never pushed for a bomb because they were ethically opposed. Lucas: But the transcripts also show that earlier, in 1942, Heisenberg had told Albert Speer, Hitler's armaments minister, that the bomb was possible but would take years and massive resources. Speer decided to focus on conventional weapons. So in a sense, the German program was a victim of its own scientific honesty and the regime's impatience. Luna: It's a strange legacy — the discoverers of fission, a Nobel Prize winner, the Uncertainty Principle — and they ended up listening to the news of Hiroshima in captivity. Lucas: Exactly. And that's the core of the story. Otto Hahn later won the Nobel Prize in Chemistry for his discovery of fission, but he was deeply conflicted. He became a vocal advocate for nuclear disarmament. Meanwhile, the Uranium Project haunted West German science for decades. The country never pursued nuclear weapons, and the 1954 Paris Agreements formally renounced them. Lucas: So the German atomic bomb never was — but the fear of it shaped the war, and the moral questions it raised shaped the postwar world. It's a reminder that in science, discovery doesn't come with a moral compass. That's something the Germans had to learn the hard way. Luna: Thanks, Lucas. That was a really nuanced look at a topic that's often oversimplified. Lucas: My pleasure. Next time, we'll pick up in the postwar era — perhaps the economic miracle or the fall of the Wall. Until then, keep asking the big questions.