United States Army during World War II

During World War II, the United States Army underwent significant changes and played a crucial role in the conflict, fundamentally shaping its purpose and structure. The primary objective of the U.S. Army during this period was to mobilize and deploy forces to combat Axis powers, including Germany, Italy, and Japan. This required a vast expansion of personnel and resources, leading to the largest military mobilization in American history up to that point.

In response to the war's demands, the Army implemented several reforms. The establishment of the Selective Service Act in 1940 allowed for the conscription of millions of American men, dramatically increasing the size of the Army from about 190,000 active-duty personnel in 1940 to over 8 million by 1945. Training programs were enhanced, and new units were formed, including specialized divisions like the Army Air Forces, which emphasized the importance of air power.

The Army also adopted more modern organizational structures and tactics, reflecting lessons learned from earlier conflicts. Innovations in strategy, logistics, and technology were prioritized to improve combat effectiveness. The integration of women into the military through organizations like the WAVES (Women Accepted for Volunteer Emergency Service) and the WACs (Women's Army Corps) marked a significant shift in personnel policy, although racial segregation remained a prominent issue within the forces.