How did presidential addresses and supreme court rulings begin to change the lives of the american people beginning in the mid-20th century?

In the early 20th cent., the court appeared to be highly conservative in its views. It showed in general a rigid adherence to stare decisis (the rule that precedents are to be followed), a tendency to prevent the states from adopting laws that restricted business in its employment practices and other activities, and little disposition to restrain the states from restricting civil liberties, as in the Plessy v. Ferguson case (1896), which upheld the right of states to enforce segregationist Jim Crow legislation in many Southern states. In the Insular Cases (1901), arising out of questions concerning the status of peoples in the territories acquired as a result of the Spanish American War, the court asserted that the civil rights guaranteed by the Constitution did not automatically apply to the people of an annexed territory, i.e., the Constitution did not follow the flag.
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