When the bombing of Pearl Harbor suddenly thrust the United States into World War II, President Roosevelt knew that industrial might would be the key to Ally victory. He needed to build thousands of ships, planes, and bombs, and that meant an urgent call for more electric power. TVA answered by building 12 hydroelectric plants and one coal-powered steam plant—simultaneously.
The resulting increase in power helped fuel factories that churned out more than 50,000 planes. During the war, power from Wilson Dam was temporarily used once again to fuel the American military effort, as a large portion of the country's nitrates and phosphorous for explosives were made at the Muscle Shoals facilities.
TVA's most storied role in World War II actually started off as a secret. As part of the Manhattan Project, TVA supplied millions of kilowatts of electricity to a top-secret facility in Oak Ridge Tennessee throughout the war. The Oak Ridge facility used nearly one-seventh of all the country's electricity in enriching uranium to produce the weapon that would dramatically end World War II—the atomic bomb.