Apathy: Apathy refers to lack of interest, enthusiasm, or concern towards something. In this case, apathy could contribute to U.S reluctance in joining the League of Nations if there was little interest among Americans.
Isolationism: Isolationism is a foreign policy approach where a country avoids involvement in international affairs and focuses on its own domestic matters. U.S reluctance may stem from isolationist tendencies prevalent at that time.
Skepticism: Skepticism involves having doubts or reservations about something. U.S reluctance could arise from skepticism towards whether joining the League of Nations would truly benefit American interests.