The high level of isolationism in the U.S. during the 1930s stemmed from the aftermath of World War I, anti-war sentiment, and concerns about avoiding foreign conflicts.
The main reason behind the high level of isolationism in the U.S. during the 1930s was primarily influenced by the aftermath of World War I. The memories of the devastating loss of lives in WWI and the findings of the Nye Committee, which suggested a profit motive for entering the war, contributed to a growing anti-war sentiment among Americans.
Additionally, the aggressive actions of totalitarian governments overseas and the desire to avoid being entangled in foreign conflicts led to the passing of Neutrality Acts in the mid-1930s, which aimed to keep the U.S. out of international disputes.
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