With criminals such as Capone supplying illegal booze, the simple act of drinking a martini became an exciting adventure for millions of Americans. And the covert thrill of drinking helped fuel a widespread youth rebellion that spread throughout society.

In earlier decades young men were expected to be conservative, industrious, and hard working. Young ladies were expected to be prim, proper, modest, and virtuous. The war, however, had changed all that.

Many young men who had served in Europe had been exposed to the sophisticated ways of Europeans who openly drank and smoked in outdoor cafes. In addition, Europeans had a relaxed attitude toward sex that was new to American youth.

Women's fashions were also influenced by Europeans, as small, helmetlike cloche hats, short dresses, made-up faces, silk stockings, short "bobbed" hair, and long strings of beads became all the rage. And every fashionable woman wore...