Just as the Second World War was wrapping up, the United States made a huge technological breakthrough: the atomic bomb. Through the Manhattan Project, the US had researched a weapon that changed the geopolitical landscape with its destructive capability, and they created an atomic bomb arms race cold war. While WWII saw Russia and the United States as allies, by the time the war was over, the world was already shifting to them becoming rivals. Unfortunately, that meant the Soviet Union had a lot of ground to catch up. If they wanted to compete with the United States, they were going to have to develop their own nuclear arsenal.
How they achieved that goal, however, is a story full of hard work, intrigue, and espionage. Just like any Cold War race, the Soviet Manhattan Project – the Soviet Union's quest to obtain a nuclear weapon better than the Americans' – was filled with drama. And the results were truly frightening, culminating in the largest nuclear detonation in the history of the human race.
It was the Germans who discovered fission in 1938, and the Soviets were extremely interested in its development. While Russian scientists tried to replicate the German experiments, once the war with the Nazis broke out and the Soviet Union was invaded in 1941, their attention was needed on more pressing projects such as radar. However, soon the Russians realized just how much power was in nuclear energy – and that both the Germans and Americans were working on uranium bombs. So, in 1943, the Soviet Union started its own atomic program under the eye of nuclear physicist Igor Kurchatov and political director Lavrentiy Beria.
While it was true that the writing was on the wall in regards to nuclear weapons, not everyone could see it. A Soviet physicist named Georgi Flerov noticed that no one was publishing any papers on fission. Of course, the reason for this was that all the top researchers in the West were knee deep in atomic weapons programs that were top secret, and the Soviet Union was busy dealing with a German invasion. So, Flerov put the pieces together and sent a letter to Stalin himself about starting their own program. However, there is little solid evidence to suggest that Stalin ever actually saw the letter.
You have to crawl before you can walk, and so it is with nuclear bombs. Though their atomic program began picking up steam in 1945 – after US President Truman officially told Stalin about the US's atomic program – the Soviets were having some trouble producing the plutonium and uranium isotopes necessary for a bomb. However, they did manage to create their first working reactor in 1948. Half a year later, they produced and detonated their first atomic bomb.
In their pursuit of the atomic bomb, Soviets cleverly targeted well-educated Western scientists, and they used various methods to turn them to the Soviet cause. What were their motivations? Many scientists were so scared of the idea of the atomic bomb that they thought no nation alone should have that much power. By giving the secret of atomic weapons to other nations, it was a balance of power that would prevent a larger catastrophe. Others also had communist sympathies like the Cambridge-educated John Cairncross, considered the first atomic spy for the Russians.