Did the League of Nations Fail Because of American Isolationism?

While the League of Nations was undermined from the outset by the absence of the United States – it was the supposed ‘keystone’ in the arch, according to Punch – this was not the proximate reason for its failure during the interwar period. Rather, it appears that the League was undermined by the selfish actions of Britain and France, as well as the problems of its own creation; it appears that the idea of a supra-national body on this scale was a unique product of the post-war climate, and was therefore misconceived and ill-suited to the rise of fascism in Italy, militarism in Japan and Nazism in Germany.