From the beginning, the peace settlement at the end of World War I left nations unhappy. President Woodrow Wilson had realized that the peace settlement included provisions that could serve as new causes for conflict. Most Americans wanted to avoid involvement in European affairs. The U.S. Senate, in spite of President Wilson's wishes, refused to ratify, or approve, the Treaty of Versailles. This tough policy began with the issue of reparations that the Germans were supposed to make for the damage they had done in the war. In April 1921, the Allied Reparations Commission determined that Germany owed 132 billion German marks for reparations, payable in annual installments of 2.5 billion marks.