Developments in the west on the atomic bomb had started before World War II culminating in the division of the uranium atom in 1938. But it was after the war that from some point on these developments became stormy. The Soviets themselves had not done much about building such a bomb, but their intelligence services worked feverishly. They had collected important information about the evolution of the American atomic bomb, mostly from their sources of counter-espionage abroad.

Many stories and disaster scenarios have been written or recorded on how actions on the building of the Soviet atomic bomb were organized. Stalin's critical developments in the Soviet Union had been difficult to bring together. Many stories yes, but it was not possible to confirm their validity. It is difficult to manage rumors, but it is worth trying to collect and present them for worldwide public information only.

In one of these stories, at one point, alarming reports began to arrive in Moscow about the construction of a nuclear bomb in the Western camp. It should be noted that the Russian community of physicists had great respect at that time. Whereas Western scientists closely informed their governments about scientific developments and their possible military implications, Russian scientists were not so lucky.

The stance of soviet scientists was somehow restricted since their academic attitude reflected the strategic and political status of their country. While the big European nations were already involved in the conflicts of war, the Soviets had entered into a pact with the Nazis abstaining from the conflict. In this context, Russian scientists were unable to contact their leaders to inform them of potential actions against the Germans.

It is worth mentioning that Soviet physicists had already discovered the spontaneous fission of uranium. Later, they claimed that it was Russian physicists who probably were the first to realize the self-sustaining nuclear chain reaction.

Despite the then non-involvement pact environment in the Soviet Union, some physicists have been quietly activated. Among them, Georgi Flerov wrote and sent letters with sketches of an experimental bomb using the gun method. At the same time, he tried to find relevant scientific information from foreign journals but realized that no such information was available because the main scientific journals contained no reference to similar research.

Flerov had no evidence at the time, but he assumed that military censorship had likely been imposed on such information. He then tried to persuade his fellow scientists that combined efforts were necessary, to join forces that is, on research with uranium. But a big obstacle was unfortunately Stalin's attitude of not paying attention to this topic. In parallel with Flerov's efforts, the secret services of the Soviet Union had done much to gather relative information. Nuclear-related intelligence reports started arriving from the west as soon as research in the military field started producing fruitful results. By the middle of 1941, they had concluded that in the west a decision had been made to build the bomb, estimating that it would take a few years to do so. In addition, information arrived describing the efforts made to produce uranium-235 by the gaseous diffusion process. One of their sources was the so-called "Cambridge Five" consisting of Soviet agents forming a group of intelligent researchers who also had access to Western intelligence plans.

However important information on the western research to produce the bomb had already been gathered in early 1942 obliging Beria to start searching for explanations. It is important to say that the developments reached a turning point after a report to the NKVD headquarters came from its London office. The report gave information on the development of the United Kingdom, in particular on the creation of a special "nuclear commission" to resolve the practical problems associated with the creation of the atomic bomb. The information indicated that such a bomb might be ready in two years, giving some technical details of a plant capable of separating uranium isotopes.

It was precisely these developments and information from the UK, which played a decisive role in Soviet defence policy during the war. Crucial developments have occurred since the adoption of Resolution 2352, which marked the beginning of the Soviet nuclear bomb program.

It is important to note that the plans of the Soviet intelligence services despite their efforts could not have gone further. The principal reason was the difficulty of understanding the reports of scientific intelligence and of course could not exploit it. But the new "Atomic" environment that was emerging in the West had forced intelligence in Moscow to react but in reality, they did not know how. Many of their executives and decision-makers, though unable to understand these scientific reports, had the feeling that something new and very powerful was about to come.

Lavrenti Beria, Stalin’s powerful security chief decided to ask for help from a group of physicists. He wanted an explanation for the nuclear research reports received but was not willing to share his intelligence reports. This is perhaps the reason that led the soviets to erroneously conclude that an atomic bomb could only be built in the distant future.

Also, they did not know how to effectively forward information on calculations of the critical mass and the gaseous diffusion method of enriching uranium. The need for collaboration with physicist Flerov and finally together influence Stalin seemed more than necessary.

After the physicist was briefed on the situation by the secret service archives, he decided to help achieve their objective. The physicist and the intelligence officers analyzed the situation and concluded that they should use in the case of Stalin non-scientific methods, but purely intelligence techniques. Thus, he decided to send Stalin a letter informing him of certain developments in nuclear research pointing out that something suspicious is emerging.

He insisted that many eminent physicists in the West had stopped publishing, suggesting that something alarming was taking place there. In other words, rather than show him specific facts and introduce measures, he did the opposite. He complained to Stalin that because nothing has been published recently in the West concerning nuclear fission something suspicious might exist. Let's do something too", he suggested!

Stalin immediately called a group of distinguished academics and accused them of their negligence in a problem that had just reached his knowledge. It is true that Stalin distrusted its scientists and did not let them see the spying data. But the carefully mixed scientific/intelligence steps that followed finally convinced the Soviet ruler in December 1942 to initiate a small-scale atomic project.

But Flerov was not completely satisfied. He indirectly asked Stalin to launch a broader program, but things became confused with real intentions. After the German forces penetrated deep into Soviet territory, scientific laboratories began to be evacuated and brilliant scholars were sent to the front.

We must remember that the decisions were taken at a time when the city of Leningrad was besieged by the Germans and the battle of Stalingrad was active. It was only after the Russian victory in Stalingrad that a list of information was shared on which "reliable physicists could rely. "Magnificent indeed material" commented some physicists, "this is exactly what we lacked". Some of them even suggested new means of spying.

Soviet intelligence agencies had during the war managed to steal the basic "plans" of the first American atomic device. They believed they were helping their researchers to avoid dangerous tests for a critical mass destination, tests that cost the other party their lives. But it was the crucial cooperation with specialist physicists which enabled the exploitation of information acquired abroad as well as an intelligent presentation that convinced Stalin.

Note: real events might have evolved differently.