Firstly, American Exceptionalism was based on the idea that America was an exceptional nation with an inherent right and ability to shape world events without entanglement in European conflicts and international rivalries. This perception was reinforced by President Woodrow Wilson’s Fourteen Points plan at the close of WWI which sought to create lasting peace through American leadership while avoiding direct engagement in any European power struggles. This notion was further supported by other prominent journalists such as Walter Lippmann who argued that America had no vested interest in Europe's troubles and therefore should not become entangled with them. Moreover, many Americans viewed their country as morally superior compared to Europe due to their non-involvement in European wars throughout history, thus making it easier for them to argue for disengagement from foreign affairs during this period. The second factor fuelling American isolationism before WWII was fear; mainly fear of economic stagnation due to over-commitment abroad or becoming embroiled into costly military engagements overseas . With memories still fresh off WWI devastation , Americans were understandably wary about getting involved again in anything which would lead them back down the same path they had just escaped from . Thus , even if some believed engaging abroad could be beneficial for US interests , they were overruled by those who worried about potential costs associated with such action . Many also feared a loss of sovereignty if America became too involved with other nations' internal politics or diplomatic disputes . All these factors combined created an environment conducive for isolationalist policies towards Europe and Asia before WWII . In conclusion , prior to WWII US foreign policy leaned heavily towards isolationism . This isolationist stance derived its roots primarily from two main sources: a sense of superiority over Europe because of its non-participation in past wars , coupled with fear that participation would lead it into an costly conflict or financial obligations it could not afford handle nor wanted anyway given its own internal challenges at home