• While the 1920s were the era of the automobile, the construction of roads took off in the 1930s with multilane engineering marvels, including the George Washington, Golden Gate, and Bay Bridges, cutting travel times.
• Electrification surged in the 1930s. Power was brought to farms. Electricity turned from luxury to a necessity.
• Electricity became a servant to washing machines, vacuum cleaners, and refrigerators, freeing up hours of household labor.
• The first supermarket opened in 1930.
• Productivity growth in the 1930s took place in utilities, farming, wholesale trade, retail, transportation, mining, and communication.
• More young people stayed in school because they had nothing else to do, resulting in a surge in high school graduation and college graduates.

The big technical leap of the 1930s could not have happened without the devastation of the depression. However, there is a limit to stress-induced innovation: The foundations of the economy itself should remain intact to support new ideas and innovations.

This balance bet...