William R. Braisted
The history of American naval diplomacy may be divided into three periods that correspond to technical developments in naval warfare and with the changing situation of the United States in world affairs. During the first century of the nation's history, when the United States enjoyed considerable security provided by the oceans separating it from Europe and Asia, its naval forces were largely directed toward protecting American merchants, missionaries, and government officials in Africa, Asia, and Latin America. This involved showing the flag to induce non-European peoples to treat Americans according to European and American conceptions of civilized practice. During the period from 1890 to 1945, the diplomatic role of the navy was revolutionized by the emergence of the United States as one of the great naval powers. To its earlier responsibilities of police and protection, the "new navy" of steam and steel added the strategic objective of defending the Western Hemisphere and a good part of the Pacific against intrusion by the European powers and Japan. After 1945 the navy joined with the air and land arms to provide the element of force behind American global diplomacy when the great military powers were reduced initially to two and finally to one, the United States.
See also BLOCKADES; THE CONTINENTAL SYSTEM; EMBARGOES AND SANCTIONS; EXTRATERRITORIALITY; FREEDOM OF THE SEAS; IMPERIALISM; PROTECTORATES AND SPHERES OF INFLUENCE.