Final answer:
The United States' economy recovered from the Great Depression chiefly due to the mobilization for World War II, which led to a surge in production and job creation that surpassed the effects of New Deal policies.
Step-by-step explanation:
The event that ultimately brought the United States economy out of the Great Depression and created jobs for millions of unemployed American workers was the mobilization for World War II. While Franklin D. Roosevelt's New Deal policies, such as the creation of the Works Progress Administration (WPA), provided some relief and employment through federal funding for infrastructure, it was the surge in production and economic activity driven by the war that truly ended the economic downturn. The entry of the United States into the war in 1941 spurred massive industrial growth and job creation as the demand for military goods increased.
Before the war, the United States faced significant economic challenges. The 1929 stock market collapse and the ensuing Great Depression resulted in widespread bank failures and unemployment soaring to 15 million people. The situation worsened with the Dust Bowl, which led to displacement and homelessness. Although the New Deal brought infrastructure projects and support for artists and writers, a second financial downturn in 1937 revealed the fragility of the recovery.
It was not until significant government spending on war production and the absorption of the unemployed into the military and war industries that substantial economic recovery occurred. This resulted in a drop in unemployment and an increase in production that finally surpassed pre-Depression levels. The lessons learned from the Great Depression influenced modern economic policy, as seen by proactive measures taken during the Great Recession to prevent a similar disaster.