Final answer:
During WWI, the U.S. did not trade with Germany due to Great Britain's blockade.
Step-by-step explanation:
The reason the U.S. did not trade with Germany during WWI was because Great Britain used its navy to blockade Germany. This meant that British ships prevented any trade from reaching or leaving Germany. As a result, the U.S. was unable to engage in trade with Germany or any other nations at war, including Great Britain.
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