What was the primary argument of Senate opponents against the League of Nations as proposed in the Treaty of Versailles?
The United States had only reluctantly abandoned its position of neutrality in World War I, and when the war was over, the enormous destruction and loss of life reaffirmed for many politicians and the American people as a whole that the United States should stay as isolated as possible from the politics and strife of Europe, and indeed, the rest of the world. Woodrow Wilson disagreed, and the Fourteen Points, his blueprint for the postwar world, had as its capstone a League of Nations, which would serve as a peacekeeping body in the new world order. Many of the other aspirations of the Fourteen Points were not met in the Treaty of Versailles and other treaties that emerged from the Paris Peace Conference, but the League of Nations was added. However, one clause in the treaty, which stipulated that troops from member nations could be used to maintain the peace, caused much consternation among Republican senators led by isolationist Henry Cabot Lodge. Arguing that the provision was a violation of US sovereignty, and that American troops could be sent to foreign countries to fight foreign battles under foreign leaders, they declined to ratify the treaty as it was. Lodge articulated the opinion of the isolationists in terms that evoked the racial and xenophobic nature of many Americans in the postwar world:
I have never had but one allegiance - I cannot divide it now. I have loved but one flag and I cannot share that devotion and give affection to the mongrel banner invented for a league. Internationalism, illustrated by the Bolshevik and by the men to whom all countries are alike provided they can make money out of them, is to me repulsive.
Wilson, convinced of the ultimate morality of his cause, declined a number of compromise measures introduced in the debates, and took his message directly to the American people in a cross-country tour that ended when he experienced a stroke. Without Wilson's agitation in favor of the Treaty, the Senate refused to ratify it, and the United States did not join the League of Nations.