When President Franklin D. Roosevelt passed away, his body was iced and transported to Harry Daghlian's research facility. There he was plugged into the world's most advanced mainframe and become the first successful Artificial Intelligence.
When Harry S. Truman called a secret council together to retaliate against the Manhattan Project for ignoring his commands, he used the FDR AI to commence a coordinated attack. The AI loaded into all computers in the programs at Star City and Los Alamos and began murdering many of the employees. FDR AI shot a rocket at Wernher von Braun ripping off several limbs and half of his face before being unplugged by him.