1920s: Women have just won the right to vote in the United States with the passing of the Nineteenth Amendment on August 26, 1920. They see it as an important victory and vow to use their votes wisely to effect important change.

Today: Most voters are apathetic about their right to vote. Many do not even bother going to the polls, and election turnout is often very small.

1920s: The first scheduled radio broadcast emanates from KDKA, Pittsburgh.

Today: Thousands of radio stations broadcast constantly throughout the United States and the world. Consumers can now subscribe to satellite radio with hundreds of commercial-free stations.

1920s: The fear of communism grips the United States as it is considered a threat to the democratic way of life. This fear comes to be known as the "red scare."

Today: With the break-up of the Soviet Union, communism is no...