Part I: American Involvement in WWI When World War I erupted across Europe in 1914, President Woodrow Wilson proclaimed the United States would remain neutral, and many Americans supported this policy of nonintervention.Women The most familiar symbol of the "Roaring Twenties" is probably the flapper6 : a young woman with bobbed hair and short skirts who drank, smoked and said what might be termed "unladylike" things; even those women who were not flappers gained some unprecedented freedoms. They could vote at last: The 19th Amendment to the Constitution had guaranteed that right in 1920. Millions of women worked in white-collar jobs and could afford to participate in the burgeoning consumer economy. The increased availability of birth-control devices made it possible for women to have fewer children. And new machines and technologies like the washing machine and the vacuum cleaner eliminated some of the household work. The Birth of Mass Culture and Consumerism During the 1920s, many Americans had extra money to spend, and they spent it on consumer goods such as ready-to-wear clothes and home appliances like electric refrigerators. In particular, they bought radios. The first commercial radio station in the U.S. hit the airwaves in 1920; three years later there were more than 500 stations in thenation. By the end of the 1920s, there were radios in more than 12 million households. People also went to the movies: Historians estimate that, by the end of the decades, three-quarters of the American population visited a movie theater every week. But the most important consumer product of the 1920s was the automobile. Low prices and generous credit made cars7 affordable luxuries at the beginning of the decade; by the end, they were practically necessities. In 1929 there was one car on the road for every five Americans. Meanwhile, an economy of automobiles was born: Businesses like service stations and motels sprang up to meet drivers' needs. The Jazz Age Cars also gave young people the freedom to go where they pleased and do what they wanted. What many young people wanted to do was dance: the Charleston, the cake walk, the black bottom, the flea hop Jazz bands played at dance halls; radio stations and phonograph records (100 million of which were sold in 1927 alone) carried their tunes to listeners across the nation. The novels of F. Scott Fitzgerald (1896-1940) chronicled the Jazz Age. Prohibition During the 1920s, some freedoms were expanded while others were curtailed. The 18th Amendment to the Constitution, ratified in 1919, had banned the manufacture and sale of "intoxicating liquors," and at 12 A.M. on January 16, 1920, the federal Volstead Act closed every bar and saloon in the United States.However, the interception and publication of the Zimmerman telegram threatening an alliance between Germany and Mexico1 and the fall of the Tsarist regime in Russia made Wilson's claims that he wanted to fight to make the world safe for democracy.Some older people objected to jazz music's "vulgarity" and "depravity" (and the "moral disasters" it supposedly inspired), but many in the younger generation loved the freedom they felt on the dance floor.U.S economic output doubled in four years (highly productive industry).The U.S. officially entered the conflict on April 6, 1917.Impact of WWI The United States became a world power.As a result, America had developed a comparative advantage in mass production of goods.Wilson was the first U.S. president to visit Europe when he attended the Paris Peace Conference2 .It had also become a major military power.