In the aftermath of the world war, with Europe in collapse, America was the most powerful country on earth. And many whose religious convictions had been severely tested by the war's destruction turned to a new faith—materialism, business, and mass consumption. Business boosters attributed American prosperity and know-how to a higher power, and many believed it was true.

Another type of power also appeared on a grand scale in the 1920s. Gone were the days of gas lighting, handcranked record players, and iceboxes kept cool with huge chunks of ice carried to the door by icemen. The United States turned on the lights in the twenties as the proportion of homes supplied with electricity jumped from 20 percent in 1919 to 63 percent in 1927. This amazing new source of power allowed consumers to plug in radios, refrigerators, toasters, sewing machines, washing machines, and other electrical appliances.

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