The essay discusses the factors that led the United States to enter World War 2 between 1936-1941, after initially pursuing an isolationist foreign policy. Key factors included America's economic and political influence not being used to curb German, Japanese, and Italian aggression in the 1930s. Additionally, America's past expansionist tendencies and victory in the Spanish-American War provided historical context for its later entry into World War 2 despite an initial desire to remain isolated from foreign wars.