The introduction of the income tax made Prohibition fiscally feasible. Women’s suffrage made it politically feasible. World War I created a surfeit of patriotism, a willingness to sacrifice, and an embrace of the expansion of federal power. By 1920 everything was in place for a bold new government intrusion into everyday life.
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At the same time as temperance was flowering, so were crusades for clean water and sanitation, which saved millions of lives. Alcohol, seen as a major scourge of civil society, looked ripe for a once-and-for-all ban that would put mankind on a new course. “Figuring per capita,” Okrent writes, “multiply the amount Americans drink today by three and you’ll have an idea what much of the nineteenth century was like.”