Prohibition.

The 1920s are now popularly perceived as an era of hedonistic rebellion against Victorian repression. Prohibition, the decade's defining institution, made dissipation a matter of principle and lawlessness chic. But the speakeasy would not have existed without the passage of the Eighteenth Amendment, a triumph for puritanism. Deriving from optimistic overconfidence in the power of law to promote human virtue, Prohibition — which became the law of the land in 1919 — was an experiment no less characteristic of the 1920s than other more rebellious experiments. Puritanism — contemporaneously defined as the fear that somebody somewhere is having a good time — remained a powerful force throughout the decade.

Wartime Influences.

The battles between puritanism and the New Freedom were triggered by the marked changes in American society resulting from World War I. Young men who had never traveled went to France. A...