One political mistake is blamed for the failure to win American adherence to the League of Nations. What was it?

1. 1. Wilson led the Peace Commission to Paris himself, so an American delegation was plainly present. 2. 2. His mistake was leaving out any leading member of the opposition Republican Party. 3. 3. Ratification had to come from a Senate with a Republican majority. 4. 4. On his return he refused even the moderate concessions that would have won that majority. 5. 5. The Senate did vote on the treaty in March 1920 and rejected it, so it was certainly shown to them. 6. 6. The League Covenant existed in writing, since it was voted on and rejected. _Source: An Outline of American History (U.S. Information Agency, 1990, public domain), section ISOLATIONISM FOLLOWS PEACE_