After being defeated during the events of Command & Conquer: Red Alert, the Soviet Union has a puppet government installed by the victorious Allies. However, they secretly build up their military and launch a surprise attack against the unsuspecting United States. Naval and air forces strike the East and West Coasts, while Soviet ground troops invade through Communist Mexico.
A retaliatory nuclear strike is foiled when the missiles inexplicably explode in their silos. In this desperate situation the player begins Command & Conquer: Red Alert 2.