Whether because of fear of entrapment, abandonment, or exploitation by European powers, for the next century and a half the United States was wary of signing treaties of military alliance as a means of guaranteeing its own security. Concern over being drawn into the war between revolutionary France and England undoubtedly influenced President George Washington to exhort Americans to avoid entangling alliances in his Farewell Address of 1796, a warning repeated by Jefferson as president four years later. In relation to Europe, treaties were seen by the United States as too "open," too "anarchic" in character. As each party to a treaty retains substantial decisionmaking capabilities, the risks were too great in a region where the United States was not likely to be the dominant party in any treaty arrangement. The United States did not sign another treaty of alliance until 1947 (the Rio Treaty) and 1949 (the NATO alliance).
This does not mean that the United States was not engaged in or active on the world stage. It simply means that the nation regarded unilateral action as in its best interests. The costs of cooperation—either in economic or military terms—were regarded as too high or the returns insufficient to warrant the risks involved in cooperation. This was not the case in continental America, where the United States was dealing with indigenous Americans and Mexico and Canada—although both those countries were integrated into the European state system. In this instance the United States readily entered into—and broke—treaty arrangements. In the Western Hemisphere the United States also felt it could best protect its interests unaided. Successive administrations felt that the issuance of the Monroe Doctrine—establishing Latin America as a sphere of interest, if not a protectorate—rendered treaties unnecessary.
In the Pacific and East Asia, on the other hand, American attitudes to treaties varied, although the major motivation remained commercial expansion. Although the United States was too late to participate in the "great game of empire" played out there by the European powers, it participated with the Western powers in the unequal treaty system they forced upon China following the Opium Wars. Following British success in the Treaty of Nanking in 1842, the United States, in the Treaty of Wanghia (July 1844), extorted similar concessions from China—mostfavored-nation status, the opening of five ports, the imposition of extraterritorial rights for Americans (legal trials for foreigners in special courts of their own nationality)—that lasted until 1942. Also, although no treaty of alliance had been entered into, a U.S. navy warship acted in concert with British, French, and Dutch ships during 1863–1864 to punish Japan for harassment of merchant shipping, and the United States shared an indemnity that Japan was forced to pay to the Western powers.
Throughout the nineteenth and the first half of the twentieth centuries, the two poles of American treaty making were territorial acquisition and amity and commerce, with its various corollaries.