What was a reason for the collapse of the american economy which led to the great depression?

Though the relief and reform measures put into place by President Franklin D. Roosevelt helped lessen the worst effects of the Great Depression in the 1930s, the economy would not fully turn around until after 1939, when World War II kicked American industry into high gear.

The boom of the 1920's rested on a weak foundation since the prosperity was not enjoyed by all economic groups.

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