By the end of the nineteenth century, American policymakers and political writers were convinced that alliances, coalitions, and ententes were all part of a dangerous concept of international relations. Convinced that alliances caused wars rather than prevented them, Americans looked upon the European political scene with contempt. Yet, at the same time, a small group of statesmen-politicians led by such ultranationalists as Henry Cabot Lodge, Albert Beveridge, and Theodore Roosevelt concluded that its size and economic power made it necessary for the United States to play an active role in international politics. As Theodore Roosevelt put it: "We have no choice, we the people of the United States, as to whether or not we shall play a great part in the world. That has been decided for us by fate, by the march of events. We have to play that part. All that we can decide is whether we shall play it well or ill."
With Roosevelt as president from 1901 through 1909, the United States had, for the first time as chief executive, a man who saw the nation's mission as much more than merely an example to others. Roosevelt—taking his cue from the social Darwinists, but adding an optimism based on the American experience—saw America's role in the world as unique and tinged with messianic destiny. He not only believed the United States was a nation with international responsibilities, he also unquestioningly embraced the idea that the fate of mankind depended upon America's willingness to accept those responsibilities. Roosevelt saw no need for anything less than American superiority in the Western Hemisphere, but he sought to avoid antagonizing Great Britain in the process. The community of Anglo-American interests had been growing since 1815, but not until Roosevelt's presidency did the government establish a strong, if unofficial, entente with Great Britain. Roosevelt's prejudice in favor of Anglo-Saxon "civilization" as well as his realistic appraisal of America's economic and military interests resulted in American influence invariably buttressing British goals in Europe. Roosevelt was not alone, as can be seen by such editorials as appeared in Harper's Weekly openly advocating American participation in the Anglo-French entente. Although Roosevelt, largely because of domestic politics, did not heed such advice, he supported various British attempts to dominate the European balance of power, the best example being his secret diplomacy during the Moroccan crisis of 1905–1906.
The political situation in Asia concerned Roosevelt deeply. Convinced that the United States had to act like a Pacific Ocean power, he even expressed a vague desire for America to join the Anglo-Japanese alliance, which was designed to delineate British and Japanese interests in China and to halt Russian expansion in the area. Although such active participation in an alliance seemed politically impossible, Roosevelt attained that goal in part without any domestic struggle. His role as peacemaker during the Russo-Japanese War found him privately applying diplomatic pressure; yet the American public, still committed to nonentanglement, approved what appeared to be a role of disinterested and uninvolved organizer of a successful peace conference. From 1905 through 1908, American and Japanese representatives held almost continuous talks about other mutual problems. Although the discussions were frequently unpleasant, a special relationship developed between the two nations. Roosevelt firmly believed that Japanese-American cooperation—the beginnings of entente—would bring peace, order, and stability to East Asia; and, as part of that policy, he recognized Japanese spheres of influence in Korea and northern China.
Roosevelt committed the United States to an active role in international affairs—a commitment that had been growing out of American power as well as his actions—and put the nation on a path that could not be reversed regardless of the rhetoric of isolation and the natural desire to avoid the responsibilities that accompanied the thrill of world power. His successors, William Howard Taft and Woodrow Wilson, reversed his policies toward Japan (with dire consequences), but the commitment to an active international role remained.