How did the outbreak of World War II in Europe lead to economic growth in the United States?
Germany and Italy depended on the United States for arms and ammunition for the war, which led to higher production.
The United States supplied countries fighting against fascism with needed materials, which led to an increase in factory jobs.
As the countries of Europe started to spend money on the war, the United States was able to borrow money for relief efforts here.
The United States sent a great number of soldiers to fight when the war started, leading to job vacancies in the United States.