United States of America, relations with. American success in the American War of Independence (1776–83) was followed by a period in which trade above all helped the British and the ex-colonists to learn to coexist. This trend was interrupted by the War of 1812, confused alike in its origins and conduct. It was inconclusive, and left Castlereagh hoping that time would ultimately resolve such contentious issues as neutral rights. British conservatives feared the appeal of American democracy among radicals at home, while governments suspected that the USA might try to exploit British involvement in any war with a European power. Disputes over the Canadian border, however, were mostly settled by 1846, while British moves towards free trade helped to persuade many in the USA that war was unnecessary. Although tensions during the American Civil War included a major scare with the North (the Trent incident in 1861–2), the British were becoming resigned to the fact that Canada could not be defended against a determined US assault. Serious imperial and naval rivalries with other powers also persuaded them after 1895 to accept such paramountcy as the USA chose to exert in the New World.

Thus the First World War found US neutrality tempered by the fact that Britain was already viewed as the least obnoxious of the imperial powers. British interference with American trade with Germany was more than offset by huge purchases from the USA, though Anglo-American relations were paradoxically very strained during the winter of 1916–17 until the resumption and intensification of the German submarine campaign brought the USA into the war in April. Relations cooled after 1918 over such matters as trade and naval rivalries until these were eclipsed by German and Japanese aggression, and American fears of the axis—especially from 1940—led to Lend-Lease and indirect assistance at sea. The USA became a belligerent in December 1941. Even so, and despite the highly successful wartime alliance (1941–5), the Attlee government briefly showed interest in a western European/British Commonwealth Third Force.

Lack of resources and the Russian threat finally persuaded the British to opt for the ‘Special Relationship’ with the USA, a relationship which—though assisted by a common language and various personal and cultural ties—was based essentially on shared interests and fears. Thus the USA frequently encouraged Britain to persevere in a world role so that it could benefit from Britain's Commonwealth bases as well as its own facilities in the British Isles (America's unsinkable aircraft carrier off the coast of Europe). Even after Britain's withdrawal from east of Suez and its entry to the EEC (1973), the two remained intimately connected in such areas as nuclear weapons, intelligence, and the pursuit of freer trade in the world. They assisted each other in the Falklands (1982), Gulf (1991), and Iraq conflicts. But relations have been weakened by the ending of the Cold War.

C. J. Bartlett