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What did the Twenty-First Amendment do?
Answer:
The 21st Amendment (adopted in 1933) repealed the 18th Amendment (Prohibition) that had been adopted in 1919.
The 18th amendment, along with acts such as the Volstead Act, had outlawed the manufacture, sale, and transportation of alcoholic beverages in the US. After the decade of the 1920's which saw many Americans openly violating the law (to the economic benefit of criminals), public opinion supported its repeal.