In late November 1989, Soviet forces launch a surprise invasion of Seattle, Washington. A combination of regular U.S. Army and National Guard led by Lieutenant Parker and Captain Bannon confront them while civilians are evacuated. Retreating south under the command of Colonel Sawyer, they capture Pine Valley, forcing the Soviets to halt. A month later the Red Army renews its assault eastward towards Fort Teller in order to disable the United States' Strategic Defense Initiative. The Soviet Union is unaware that the project is a bluff and its existence has thus far kept it from launching a nuclear strike. Therefore the facility's defense takes top priority, and Sawyer and his forces engage in a series of delaying battles en route to the Fort. However, Soviet forces overwhelm them at Cascade Falls and a plan is made to launch a nuclear strike at the town, ensuring victory but needing volunteers to pin the enemy down. An apologetic Bannon accepts. The tactical nuclear missile is fired at the town; annihilating Bannon, his company and the Soviet forces.

Months earlier at the outbreak of the war, diplomats from both sides had failed. Sawyer, Parker and Bannon serve in France as part of a NATO counteroffensive against a Soviet invasion near Marseille, but while successful, Bannon's negligence results in the death of the French liaison, Commandant Sabatier. Later, they are sent on a secret mission inside the Soviet Union to retrieve intelligence from a crashed prototype B-2 bomber, which leads them to a Soviet naval yard where they destroy submarines to be used in an invasion of the U.S. East Coast, but during this Bannon accidentally kills surrendering Soviet troops. Later, Parker and the battalion assist U.S. Army Rangers in fighting off the aforementioned invasion of New York City. Spetsnaz intend to store chemical weapons inside the Statue of Liberty and release them over Manhattan. With Parker's effective assault Liberty Island is retaken and an air strike that would destroy the iconic statue is called off.

Returning to the present after the nuclear strike, the People's Republic of China has entered the war as a Soviet ally. China launches attacks into Asia, and sends an invasion fleet to reinforce the Soviet beachhead in Seattle. The U.S. President orders the surviving Army units from the attack on Cascade Falls to recapture Seattle, and as a backup plan orders a nuclear strike against the city should this fail. Sawyer, desperate to avoid another Cascade Falls, orders his forces to attack before the Chinese can land. They succeed in breaking through the Red Army's defense perimeter around Seattle, and capture Puget Sound to secure Soviet anti-ship missile launchers for use against the Chinese fleet. The reinforced US battalions launch their counterattack, spearheaded by the 5th battalion. Seattle is retaken from the Soviets before the Chinese fleet arrives, thus delivering a decisive blow as the Chinese are unable to launch an amphibious assault themselves. Consequently, the fleet return to China, with a conclusion that Parker may be called upon to fight later on.