President Woodrow Wilson had realized that peace settlement included unwise provisions that could serve as new causes for conflict; he'd placed many of his hopes for future in League of Nations; however, this organization wasn't very effective in maintaining the peace
1 problem was failure of US to join the league; most Americans didn't wish to be involved in European affairs; despite Wilson's wishes, US Senate refused to ratify (approve) Treaty of Versailles; that meant US couldn't be member of League of Nations, which automatically weakened organization's effectiveness; as time would prove, remaining League members couldn't agree to use force against aggression