How did the 1940s change America?

This is the study of social behavior A professional in this field may study intergroup relations between African Americans and Asian Americans for example? What was flannel originally made from? Was William Lloyd garrison an abolitionists? What did the victory at saratoga show the french? A key enlightenment thinker whose idea of social contract between people and their government appealed to colonial leaders was? What were some reasons people did not survive the Mayflower? Who invented the 2 dollar bill? What was the political motivation for the US in ww1? Why was the US foreign policy following world War 1? What proposed protecting slavery by restoring the Missouri compromise? What percent of the slaves were brought to US? What was the most likely situation of the southern plantation owner after the war? What poisenes gases that killed the most people during ww1? Why did the American Indians start smoking? What is the value of an 1881-CC PCGS MS64 Morgan Silver Dollar? What is the story behind the extra hand on the Iwo Jima memorial? What is value US 1922 silver dollar? How did slave owners get their slaves? What were the differences in the north and south? What did the Missouri Compromise the Compromise of 1850 and Bleeding Kansas have in common?

How did the 1940s change America?