Wilson hoped that the American people would support the plan for a “League of Nations.” By law, the U.S. Congress had to approve it by a vote. He spent nearly a month traveling across the United States, campaigning and explaining to the public the necessity of establishing the League. He said that the League of Nations was the only hope for achieving world peace and preventing another world war. During this long nationwide speaking tour, Wilson’s health grew steadily worse.

After prolonged debate, the Senate refused to ratify the League of Nations treaty. Many senators feared that if the United States joined the League, it would lose its independence and freedom. The Senate voted down the treaty, shattering Wilson’s plan to bring the United States into the League of Nations. The majority of Americans were focused only on domestic affairs and did not want to be involved in European matters.

Later history proved that Wilson was right. He had repeatedly warned that if the nations of the world did not work together to safeguard peace, brutal wars would break out again. Indeed, twenty years later, the Second World War erupted. Its destructive power and loss of life far exceeded that of the First World War.