1920s: Amelia Earhardt is the first woman to fly across the Atlantic Ocean.

Today: Women of all ethnicities train as commercial, military, and private pilots, flying all over the world for companies, governments, and individuals.

1920s: The first scheduled television broadcast airs in New York City.

Today: Countless television programs air constantly through cable and satellite connections. Programs air in numerous languages from a vast number of networks, stretching far and wide across the entire globe.

1920s: The most famous U.S. stock market crash occurs, spiraling the world into an economic crisis.

Today: The world economy exists on a precarious balance that could easily be disrupted with war, shortages, or unemployment.

1920s: Lenin, Hitler, and Mussolini all begin their rise to power in their respective countries, a precursor to World War II.

Today: With heavy political unrest around the world, the United States...