Roosevelt supported helping allies based on protecting US security from Nazi threats.
Roosevelt used facts to support his argument that the United States should help its allies in the fight against Nazi Germany. He emphasized that by aiding Britain and Russia, the US was indirectly protecting itself from Nazi threats. Roosevelt believed that a successful German invasion of Britain could eventually pose a direct threat to US security, as Nazi-controlled British naval and air forces could turn against the United States.
https://brainly.com/question/20711140