The United States entered<span> the war because of the Germans' decision to resume the policy of unrestricted submarine warfare, and the so-called "Zimmerman telegram," intercepted by the British, in which Germany floated the idea of an alliance with Mexico.
mark brainliest
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The Americans controlled the land between the Great Lakes, Ohio River, and Mississippi River.
World war 2
since the cause of the cold war was world war 2, it could only be that as an answer.