How did the U.S. Government obtain the massive Military arsenal in order to fight World War 2?

The U.S. Government significantly increased its military arsenal for World War II through a combination of rapid industrial mobilization, government contracts, and the establishment of programs like the War Production Board. Factories shifted from civilian to military production, producing vast quantities of weapons, vehicles, and supplies. Additionally, the Lend-Lease Act allowed the U.S. to supply Allies with military equipment, further bolstering its own capabilities. This collaborative effort between the government and private industry enabled the rapid expansion of the U.S. military arsenal.