What arguments did Americans make against involvement in the war in Europe Why did President Roosevelt and many others believe it necessary to block German and Japanese expansion?

Americans against involvement in the war in Europe often argued that the United States should prioritize isolationism, focusing on domestic issues rather than foreign conflicts. They believed that entering the war would lead to unnecessary loss of American lives and entangle the nation in European affairs. In contrast, President Roosevelt and others viewed blocking German and Japanese expansion as crucial for global stability and American security, believing that unchecked aggression would threaten democracy and lead to further conflicts that could eventually draw the U.S. in regardless. Thus, they felt it was essential to intervene to prevent the spread of totalitarian regimes.