Final answer:
The Twenty-first Amendment repealed the Eighteenth Amendment (Prohibition), making the production and sale of alcohol legal again nationally in the USA. This greatly reduced the illicit alcohol trade. While the authority to regulate alcohol was returned to individual states, laws varied across states.
Step-by-step explanation:
The Twenty-first Amendment had a substantial effect on the sale of illegal alcohol in the United States. It was passed in 1933 as a direct response to issues stemming from Prohibition, which had been legislated by the Eighteenth Amendment and the Volstead Act. Notably, the Twenty-first Amendment repealed the Eighteenth, making the production, distribution, and sale of alcohol legal once again on a national scale.
This legal reversal heavily reduced the demand for the services of bootleggers, rum-runners, and other agents of illegal alcohol production and distribution. These figures had previously profited vastly from the illegal alcohol trade due to the widespread public desire for alcohol despite Prohibition. Therefore, the Twenty-first Amendment effectively undermined the illicit alcohol market.
Importantly, the amendment did not make alcohol legal only in the states that ratified it — instead, it repealed Prohibition on a federal level. However, prohibition laws at the state and local level remained in place where they existed and could still be introduced. While the authority to regulate alcohol was returned to the states, this did not automatically establish regulations. Each state had the freedom to dictate its own alcohol laws.
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