Why did the US rejected the Treaty of Versailles?

Answer 1

The Senate rejected the Treaty in March 19, 1920

President Wilson did sign the Treaty of Versailles, but he had foolishly refused to bring Representatives and Senators, particularly Henry Cabot Lodge, the majority leader in the house. This may have biased the legislature against the treaty, but the main reason the U.S. did not agree to the Treaty of Versaille was not that they thought it was too harsh, it was that the League of Nations had become part of the treaty. The U.S. did not want its foreign policy decided by another body, so they rejected the treaty. There is a certain irony that the League of Nations was the addition that the legislatures disliked, as it was the only part of Wilson's 14 points to make it onto the Treaty.