<span>The Great Depression had started after the stock market crash in October 1929
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That statement is true
When presidents are elected with popular mandate, it is very easy for the presidents to pass any laws that he/she wants because their sheer popularity would give overwhelming public support that put pressure for the opposition to conform.
Since Kennedy was elected by a slim margin, a large portion of public still oppose his policies during earlier years of his presidency. This make it easy for his opposition to limit his movement so he can't pass the policy that he wants.
Economic: The south lost much of its agricultural land due to it being destroyed in battles, and the loss of slavery meant serious economic downfall because their industry relied heavily on slave labour. However, the North was more industrialised, so it benefitted from the added railroad and the manufacture of wartime products.
Social: 2% of the population was killed; many lost loved ones and family members. Also, racial prejudice resulted in the formation of the KKK by many whites who were angry that African-Americans had been freed-- as well as the Jim Crow laws being enforced
Political: 13th, 14th and 15th amendments passed in the constitution