As the Second World War began, so did the race to build the atomic bomb.

All major powers set out to make new discoveries in the field of nuclear technologies. The Allies only knew one thing - if they lost the race the results would be catastrophic. Driven by fear, the Allies began the Manhattan Project led by theoretical physicist J Robert Oppenheimer.

Germany began with an overwhelming head start, but in 1945 the Allies beat them to it. So why couldn’t Germany keep up? This is the story of the world’s first Nuclear Arms Race.

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Oppenheimer vs Heisenberg


Voice over: "In October 1939, Albert Einstein signed a letter to President Roosevelt. It warned that the Nazis may be on the brink of creating a devastating new superweapon. At this point, even Einstein had no idea just how destructive this weapon would turn out to be. In the letter, he describes a potential atom bomb being used to destroy a port. Little did he know a mere six years later, the Allies would possess a weapon capable of levelling entire cities in a matter of seconds."

Collections footage voiceover: "August 5th, 1945, one B-29 left on a special mission. That airplane carried the atomic bomb." 

Voice over: "As the Second World War began, so did the race to build the bomb. All major powers set out to make new discoveries in the field of nuclear technologies. The allies only knew one thing, if they lost the race, the results would be catastrophic. Driven by fear, the Allies began what would become known as the Manhattan Project, led by J. Robert Oppenheimer. Germany began with an overwhelming head start, but in 1945, the Allies beat them to it. This is the story of the world's first nuclear arms race." 

James Bulgin, Head of Public History, IWM: "Nuclear fission is basically the process of separating an atom into smaller parts by firing neutrons into the atom nucleus to create energy. The energy that's contained within the centre of the atom is the strongest in the known universe. Finding ways to release this offers the means of accessing almost unfathomable power. It was not actually until 1938, a team led by the German scientist Otto Hahn first achieved nuclear fission."

Voice over: "It was this discovery that made the nuclear bomb a possibility." 

James Bulgin: "Basically, uranium is essential for any atomic or nuclear bomb, and there isn't that much uranium in the world. So it's scattered all over the place, so there's a kind of a fight to get to the materials. And then once you've gotten materials for it, to get the tiny, tiny bit of the material that's necessary in order to create a nuclear device." 

Voice over: "Germany had a huge advantage with easy access to the large deposits of uranium found in Czechoslovakia. They also had a large roster of world renowned scientists at their fingertips. So whilst the US was only beginning to consider nuclear research. The Germans had already established the Uranverein; a collection of the country's most elite scientists. Its members included Otto Hahn and the man who would later become synonymous with German nuclear research, Werner Heisenberg."

James Bulgin: "And they realised immediately that a nuclear bomb would theoretically be possible, but they were also hugely exercised by the challenge of how to get there. This Uranverein evolved into a group that was put under the control of the military."

Voice over: "This new military control signaled the German government's commitment to the project. It wasn't long before similar discussions were also being held in Britain. The MAUD committee was established in early 1940 and their job was to determine if a nuclear bomb was actually possible."

James Bulgin: "So after about 15 months of research within the MAUD Committee, the so-called 'MAUD Report' was released. So the report laid out the technical means or they outlined, the technical means by which a bomb could be created and what it said is that this is definitely possible. And that conclusion provided a massive impetus to everything that followed, particularly within the Manhattan Project." 

Voice over: "So the Germans had the Uranverein and Britain formed an official nuclear weapons program called Tube Alloys. So what about the United States? They had been doing some research of their own, but were nowhere near as advanced as the British or Germans. Only when they got their hands on the MAUD report did the US realise the potential of nuclear weapons. The now famous Manhattan Project began soon after with Robert Oppenheimer at the helm. The race for the bomb had truly begun. Back in Germany, Heisenberg, now head of the Kaiser Wilhelm Institute for Physics, was summoned to meet with Germany's new minister for armaments. During their discussion, Heisenberg told the minister that with enough money and personnel, a bomb could be ready by 1945. It would seem that the race was neck and neck." 

James Bulgin: "In 1943, the UK and the US signed a secret agreement that was known as the Quebec Agreement that stated that the two countries should pool their collective resources to work together on the creation of the bomb. There were certain conditions attached, things like they would never release the weapon without mutual agreement, and they would never allow information about it to go to any other parties without agreement."

Voice over: "At its peak, the Manhattan Project would employ over 130,000 people at a cost of more than $2 billion. It encompassed all areas of nuclear research and facilities all across the country. Oppenheimer ran the team tasked with building the bomb at a facility in Los Alamos, New Mexico. The allies were well and truly committed to the cause. While they worked on their own bomb they also made efforts to sabotage the Germans.

In December 1944, Heisenberg travelled to Switzerland to deliver a lecture on nuclear physics at the University of Zurich. In amongst the audience was an American agent who had orders to immediately shoot Heisenberg if his lecture indicated that the Germans were close to completing a bomb of their own. These actions show us just how paranoid the Allies were right up until they won the race themselves." 

On the 16th of July, 1945, the world's first nuclear bomb was detonated in a desert in the South of New Mexico."

Voice over: "Oppenheimer was able to work with all the various different people in this place and bring them together and to get what needed to be done, done. That didn't necessarily make him well liked and it didn't necessarily make him likeable. But in some respects, I suppose that doesn't really matter because he had a job to do and he did it."

Voice over: "So Germany had lost the race. But how close did they actually get to building a bomb of their own? Whilst Oppenheimer was celebrating the success of the first nuclear tests in July 1945, Heisenberg was being held here at Farm Hall in Cambridgeshire with nine other top ranking German scientists having been captured by the Allies. What they were not aware of was that the entire building had been bugged.  From these conversations, the Allies would finally learn the truth about Germany's nuclear weapons program."

James Bulgin: "So Germany wasn't able to get anywhere near the size and scale and the level of resource necessary to do what was done within the Manhattan Project. That's the first thing. They'd also made this mistake entirely of their own volition to send some of the most brilliant minds or to force some of their most brilliant minds to other countries because these individuals happened to be Jewish."

Voice over: "On August 6th, the scientists at Farm Hall were informed that the first nuclear weapon to be used in war had just been dropped over Hiroshima in Japan. The conversations that followed revealed just how unmotivated many of the leading German scientists actually were. In fact, many of them indicated they were glad the Allies had won. Heisenberg would go on to claim that he had never seriously contemplated actually building a bomb and had actively discouraged any discussions on the matter. 

He was afraid of failure and the potential punishment a fascist government might inflict upon him should he ask for hundreds of thousands of employees and billions in funding only to produce nothing. So it turns out there was never any race at all. But the Allies didn't know this. It was the constant fear of an imagined German bomb that drove them to accelerate their own research." 

James Bulgin: "Hitler saw the Second World War as a means of creating a new world order, and he would undoubtedly have considered using any means to do that at his disposal. Looking at what he did without the bomb, looking at his attitude to different people in different parts of the world, he had no hesitation whatsoever about doing absolutely inhumanly brutal things. Then you can see why the Allies would have been so concerned about him having it." 

Voice over: "Following the second nuclear bombing in Nagasaki it was apparent that the world was a very different place. Through their network of spies, the Soviets, who had been a step behind the Allies the entire way, had managed to get hold of the blueprints to the first nuclear bomb. Oppenheimer would campaign for non-proliferation and attempt to prevent the nuclear arms race that would inevitably follow. But it was too late. A new race was beginning this time between the United States and the USSR." 

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