For starters, technology developed and now a lot more people could hear these adresses and see them on TV and hear them through the radio and they could be recorded and studied. The Supreme court decisions were important because they decided what would happen to people and their rights. For example, the supreme court first decided that separate but equal was a good doctrine, but later they decided it was unconstitutional. The addresses could affect public opinion to support something that the congress didn't want, and the supreme court would act on behalf of the people.