1930s: The United States is in the midst of the Great Depression. The unemployment rate reaches more than 23 percent, and poverty and hunger are common in many areas.

Today: The United States is in the midst of an economic downturn. The unemployment rate rises from a thirty—two—year low of 4 percent in 2000 to hover in the 5 to 6 percent range in 2002.

1930s: Following the widespread adoption of trucks in the United States in the 1920s, the railroads lose business on their freight trains.

Today: Although the railroads' percentage of domestic freight traffic has decreased at a relatively steady rate since World War II, their higher percentage of freight traffic than trucks has been maintained.

1930s: During the Great Depression, many railroads fall into bankruptcy. Those that survive do so in part because of their adoption of new technologies, such as the diesel...