It was the end of World War II. FDR's New Deal had redefined American politics. Taxes were at an all-time high. The bombing of Hiroshima and Nagasaki had created a fear of total annihilation. The rise of secret government agencies and sanctions on business had many watching their backs. America's sense of freedom was diminishing... and many were desperate to take that freedom back.
Yes, for those who played the game it is essentially the prequel.