Final answer:
The Great War was not caused by isolationism, but rather by imperialism, nationalism, and militarism.
Step-by-step explanation:
The correct answer is Isolationism. Isolationism refers to a policy of avoiding involvement in international disputes, and it was not a direct cause of the Great War. The main causes of the Great War were Imperialism, Nationalism, and Militarism. Imperialism refers to the competition among European powers for colonies and resources, while Nationalism refers to intense loyalty and pride in one's own nation. Militarism refers to the arms race and the buildup of militaries in the years leading up to the war.
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