As the possibility of World War II began to make itself felt in Europe, German scientists uncovered the possibility of nuclear fission. In the years that followed, fear of nuclear weapons falling into Hitler’s hands became one of the most powerful driving forces behind the US effort to make its own bombs (the Manhattan Project) and J. Robert Oppenheimer, often referred to as the “father of the atomic bomb.”
But it seems that Nazi Germany was not even on the verge of developing a truly viable atomic weapon.
Nuclear fission was actually discovered by the Germans.
Nuclear fission was first discovered in 1938 by German chemists Otto Hahn and Fritz Strassman, and physicists Lise Meitner and Otto Robert Frisch, working at the Kaiser Wilhelm Institute for Chemistry in Berlin. Their collective work revealed the surprising nature of fission, finding that when a neutron struck, the uranium nucleus split in two, releasing an enormous amount of energy.
In April 1939, just months after nuclear fission was discovered, Germany launched its secret program called the Uranverein, or “uranium club,” to harness the power of this new scientific breakthrough. Initial progress was slow as Germany began invading Poland in September 1939 and many of the country’s young minds had to join the army.
However, rumors of this nuclear program spread to other countries. On August 2, 1939, the “Einstein letter” was sent to US President Franklin D. Roosevelt. The letter, written by Leo Szilard and signed by Albert Einstein, warned of how Nazi Germany had the potential to develop “new types of extremely powerful bombs” and suggested that the United States should launch its own nuclear program.
At this point, it may seem surprising that, although Germany was clearly ahead, it did not get to the bomb first.
Although many prominent Jewish scientists had fled Germany at the time, there were still many successful scientists in the country. Army physicist Kurt Diebner, commissioned by Hitler himself, was chosen to lead the German nuclear weapons program to investigate military applications of nuclear fission.
Another key figure in the program was pioneering quantum physicist Werner Heisenberg, known for his uncertainty principle. Many important scientists such as Abraham Esau, Paul Harteck, Walther Gerlach and Erich Schumann were also on the team.
However, this stellar cast was not enough. Some clues to the failure of the project can be seen in the transcript of a conversation between Germany’s leading nuclear physicists on August 6, 1945, when the United States dropped the atomic bomb on Hiroshima, Japan.
Why didn’t the Nazis succeed?
Heisenberg seems to blame the lack of people working on the program, noting that the US has 180,000 scientists working on the Manhattan Project, far more than the Germans. Harteck, on the other hand, emphasizes the lack of money invested in the project.
Another suggestion was that the German team was full of big egos that let the team down. As physicist Horst Korsching puts it, “Americans are capable of real collaboration on an enormous scale. In Germany this was impossible. Each said the other was unimportant.”
Another explanation suggests that top Nazi administrators were not willing to invest heavily in nuclear technology unless there was demonstrable proof that they could win the war. Atomic physics was largely unknown at the time, and Hitler preferred to invest much more in promising V-2 long-range rockets.
Professor Mark Walker, in his book on the history of Nazi nuclear ambitions, states that the German nuclear program was “frozen at the laboratory level” during the Second World War. Worn by organizational problems, Walker writes, scientists struggled to build a primitive nuclear fission reactor and even failed in this relatively “modest task.”
Research in 2019 revealed more information about the problems Germans face. Scientists at the University of Maryland tried to trace the uranium cubes used by the German team and concluded that the central laboratory was not sufficient to build a self-contained nuclear reactor.
Ironically, there were other stockpiles of uranium elsewhere in Germany, but their tactics of conducting separate and competing experiments meant they didn’t have enough supplies to work with. Just as Korsching suggested, unlike Germany, the US’s Manhattan Project took a much more collaborative approach, pooling and distributing its resources.
The German program was also thwarted by a major military defeat at a crucial time. After the invasion of Norway in 1940, the Germans seized the Vemork hydroelectric power station and used it to produce heavy water, a vital component for nuclear reactors.
Realizing the critical role of this plant for the Nazis, the Allied forces began reducing heavy water supplies by carrying out a series of strategic bombings against the plant. The biggest blow came in 1943 when Norwegian commando forces attacked the facility, followed by another Allied bombing attack. Attempts to transport the remaining supplies out of the country were thwarted by Norwegian resistance fighters, who sank the ferry in Lake Tinn.
Joachim Ronneberg, the Norwegian leader of the commando team that blew up the facility, told the New York Times in 2015, “There was a lot of stuff that just happened by chance. We didn’t have a plan. “We were just hoping for the best situation,” he said.
Ronneberg added that if this daring mission failed, London “could look like Hiroshima”.