Why couldn't Franklin Roosevelt declare war on Germany as soon as the UK had?
A. US public opinion favored joining the Germans and fight the British.
B. The Soviet Union declared war on Germany and FDR couldn't fight along side a communist country.
C. US had a policy of isolationism.
D. The US declared war on Germany the day after the UK had.
The rejection of the League of Nations treaty in 1919 marked the dominance of isolationism from world organizations in American foreign policy. Despite Roosevelt's Wilsonian background he and acted with great care not to provoke isolationist sentiment.