What was an unintended consequence of the Eighteenth amendment ?

Prohibition was enacted to protect individuals and families from the “scourge of drunkenness.” However, it had unintended consequences including: a rise in organized crime associated with the illegal production and sale of alcohol, an increase in smuggling, and a decline in tax revenue.
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Countries trade with each other when, on their own, they do not have the resources, or capacity to satisfy their own needs and wants. By developing and exploiting their domestic scarce resources, countries can produce a surplus, and trade this for the resources they need. You can integrate all of this into your question. Hope this helped.