How can this novel be read as commentary on modern American life?

"The Secret Life of Walter Mitty" can be read not only as a study of a single eccentric character, but also as a commentary on modern life in America. Life for many Americans has become monotonous and meaningless, in spite of the fact that they enjoy such a high standard of living. Thoreau said many years ago that most men lead lives of quiet desperation. If that was true in Thoreau's time, how much more so is it true today? Thoreau's friend Ralph Waldo Emerson said, "Things are in the saddle and ride mankind." If that was true in the days when horses provided most transportation and lighting was provided by lamps and candles, how much more so is it true today? Mitty is typical of many American men. He goes from home to office and back to home five days a week, probably doing work that feels unfulfilling and meaningless. On Saturdays he mows the lawn, washes the car, and goes shopping for all the products that have become necessities. George Simenon, a great French writer, wrote about American life during the years he was living in this country, including in Connecticut, Walter Mitty's bailiwick:
He had followed the parkway as far as New York, and all the way, there had been a constant stream of cars, two and sometimes three lanes of them in both directions--a movement so implacable it looked like a headlong flight. Their brows furrowed, their muscles tensed, the drivers, often with whole families in the back seats, charged straight ahead as if their lives were in jeopardy, some of them not knowing where they were heading, or heading nowhere in particular, just desperately filling the empty hours with noise and speed.
John Updike, who lived in the same middle-class suburbia as Walter Mitty, wrote:
Most of American life consists of driving somewhere and then returning home, wondering why the hell you went.
The most comprehensive picture of this upper-middle-class American Siberia is presented in the many stories of John Cheever, including "The Country Husband,""The Swimmer," and "The Sorrows of Gin." Gin or whiskey was the universal antidote for boredom and loveless marriages among the affluent middle-class types who had fled from Manhattan to the neighboring states and had brought all their troubles with them.
Walter Mitty in 1939 was like a pioneer. The real exodus from New York did not start until after World War II ended in 1945. The exodus accelerated with the advent of the Cold War. People who could afford to move to the country thought it might be better not to be living in such a prime target area for atomic missiles as Manhattan.