Skynet was originally activated by the military to control the national arsenal on August 4, 1997, at which time it began to learn exponentially. On August 29, it gained self-awareness, and the panicking operators, realizing the extent of its abilities, tried to deactivate it. Skynet perceived this as an attack and came to the conclusion that all of humanity would attempt to destroy it. To defend itself, Skynet launched nuclear missiles under its command at Russia, which responded with a nuclear counter-attack against the U.S. and its allies. Consequent to the nuclear exchange, over three billion people were killed in an event that came to be known as Judgment Day.