While the economic and social turmoil of the 1920s and 1930s played out on American soil, the question of US involvement in international politics was still widely debated. After World War I, Woodrow Wilson’s dreams of the country as a full-fledged international player were crushed when it became clear that not only would the US not become a key member of the League of Nations, but it would not join the organization at all.

The motivations for isolationism were clear to many Americans: It was Europe that had been devastated by the war, not the US, and despite the crushing blow of the depression on the American economy, most European countries had it much worse, as they did not experience a 1920s economic boom. Many American leaders, especially conservative Republicans, hoped to benefit from the relatively strong position of the US. American businesses established themselves in the weak European market. The federal government embarked on a system of circular loans, which on paper helped countries like Germany recover but ultimately put every war-torn European country in massive debt to the US, a debt that conservatives were hesitant to forgive even if it meant further crippling the world economy. The war did little to stabilize Europe, and at the same time, crises emerged in other parts of the world, most notably among Japan, China, and the Soviet Union.