How the federal government and city government changed their role?

During the Great Depression, the role of the federal government changed tremendously.  Before the Depression hit, the federal government did little or nothing to help people financially.  This was not seen as something the government ought to do.  With the Depression came a change in this perception.  President Roosevelt's New Deal made government responsible for helping people in many ways.  These ways ranged from guaranteeing that they would not lose money they had deposited in.
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