The Emergence of American Internationalism, 1901-1921
During the first two decades of the twentieth century, the United States rose to the pinnacle of world leadership, after intervening militarily on the European continent for the first time in history in World War I. Yet after a bout of internationalist fervor that was aroused by the war, the subsequent peace settlement and the battle between Woodrow Wilson and the Senate over American membership in a league of nations, the United States returned, even if somewhat incompletely, to the isolationism that characterized American foreign policy in the prewar period.
The assassination of William McKinley in 1901 brought to the White House one of the most colorful of America's presidents, Theodore Roosevelt. Brash, aggressive, flamboyant, but intelligent, Roosevelt was the son of a well-to-do New York businessman and banker. Throughout his life he had tried to compensate for a sickly youth by emphasizing "manly" activities--including horseback riding, boxing, weight lifting, then politics as state assemblyman, police commissioner of the city of New York, assistant secretary of the Navy, Rough Rider in the Spanish American War, governor of New York, and vice president in McKinley's administration. Concluded one historian, Richard Hofstadter, "A profound and ineluctable tendency to anxiety plagued him." Yet, as president, Roosevelt displayed an astute ability to rein in his aggressive tendencies and apply reason and often wisdom to the conduct of the nation's diplomacy.1
No individual more than Roosevelt inspired the emergence of internationalist sentiment in America at the turn of the century. Isolationism, he believed, may have been a wise course for an infant United States, but it was no longer possible in the twentieth century. "The increasing interdependence and complexity of international political and economic relations," he told the Congress in 1902, "render it incumbent on all civilized and orderly powers to insist on the proper