The document discusses the causes of the failure of the League of Nations. The main causes were: (1) it was not universal in membership since the United States did not join; (2) decisions required unanimity which proved detrimental; and (3) it did not completely prohibit war and its provisions were not strongly enforced. Other weaknesses included a lack of participation by major powers, domination by some states, and a lack of cooperation between member states. Overall, the League failed to achieve its goal of preventing another world war due to these constitutional and organizational defects.