Stalin turned to the Soviet Academy of Sciences to find the best administrator to lead the program and so the Soviet Academy of Sciences chose Kurchatov for his wide experience in nuclear physics. Ioffe recommended Kurchatov to Vyacheslav Molotov, who advised Stalin to appoint Kurchatov as the formal director of the nascent Soviet nuclear programme and the development of Soviet nuclear weapons began in the 1940s. Kurchatov switched his research first to protecting shipping from magnetic mines and later to tank armour and finally to nuclear physics.