Soviet atomic bomb project

The Soviet atomic bomb project was the classified research and development program that was authorized by Joseph Stalin in the Soviet Union to develop nuclear weapons during and after World War II. Although the Soviet scientific community discussed the possibility of an atomic bomb throughout the 1930s, going as far as making a concrete proposal to develop such a weapon in 1940, the full-scale program was not initiated and prioritized until Nazi Germany invaded the Soviet Union. Because of the conspicuous silence of the scientific publications on the subject of nuclear fission by German, American, and British scientists, Russian physicist Georgy Flyorov suspected that the Allied powers had secretly been developing a "superweapon" since 1939. Flyorov wrote a letter to Stalin urging him to start this program in 1942. Initial efforts were slowed due to the German invasion of the Soviet Union and remained largely composed of the intelligence gathering from the Soviet spy rings working in the U.S. Manhattan Project. After Stalin learned of the atomic bombings of Hiroshima and Nagasaki, the program was pursued aggressively and accelerated through effective intelligence gathering about the German nuclear weapon project and the American Manhattan Project. The Soviet efforts also rounded up captured German scientists to join their program, and relied on knowledge passed by spies to Soviet intelligence agencies. On 29 August 1949, the Soviet Union secretly conducted its first successful weapon test (First Lightning, based on the American "Fat Man" design) at the Semipalatinsk-21 in Kazakhstan. Stalin alongside Soviet political officials and scientists were elated at the successful test. A nuclear armed Soviet Union sent its rival Western neighbors, and particularly the United States into a state of unprecedented trepidation. From 1949 onwards the Soviet Union manufactured and tested nuclear weapons on a large scale. The nuclear capabilities these tests helped develop were crucial to projecting and maintaining its global status.