Also, the League of Nations, which had been created by the treaty, usually had too little power to stop wars from happening. Japan took Manchuria, but the League did not stop that from happening. Italy invaded Ethiopia, the Ethiopian emperor begged the League to help him, but it did not do much. Germany, Japan and Italy left the League, became the Axis powers, invaded many peaceful countries, and caused World War II. The United States and for some time the Soviet Union did not even join the League even though US President Woodrow Wilson had pushed for his idea to go into the treaty. The League was never taken seriously although it had been created partly to check that the treaty was being followed. 