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Mahan, Alfred T.

Mahan, Alfred T. (1840–1914), naval officer and theorist.Born to Mary Okill and Dennis Hart Mahan, the latter a professor of civil and military engineering at West Point, Mahan became a career naval officer. He also became a historian and strategic analyst upon his appointment to the new Naval War College in Newport, Rhode Island, in 1885. Over the following quarter century, he wrote some of the most influential works on history and strategy ever produced.

Mahan's studies range widely, incorporating innovative and resourceful historical research and analysis with the perceived strategic and political needs of his day. Though his writings were long ago distilled into dogma from which U.S. naval doctrine has frequently been derived, Mahan himself aimed for accuracy and insight as much as for political or strategic influence. In fact, by the 1906 all‐big‐gun battleship controversies, Mahan had already been outpaced by enthusiasts willing to go even further in defense of these behemoths of concentrated fire.

Much of Mahan's forty‐year naval career passed with barely a hint of his future influence. Prickly young Mahan completed two years at Columbia College before entering the U.S. Naval Academy's Class of 1859. His Civil War service was limited to blockade duty except for a few hours of combat during the assault on Port Royal. In successive postwar assignments, he rose slowly through the ranks without distinction. Most of his cruises were on the remote Pacific or Asiatic Squadrons, reinforcing his alienated nature and encouraging his chauvinistic views toward the peoples of the Pacific Basin. His High Church Episcopal beliefs aggravated the disdain he felt for most people—naval officers, sailors, and foreigners alike.

Mahan's most famous and important work—The Influence of Sea Power upon History, 1660–1783—first published in 1890, suggests the main thrust of his historical efforts. From 1885 to 1893 he was assigned to the Naval War College, briefly as a professor and soon as president of the fledgling institution. In the years before his retirement in 1896, he prepared his most influential studies. Originally, these were designed for his midlevel officer students. They quickly lost their heuristic value, becoming instead primers of international relations, force, and diplomacy. Over the course of a long second career, Mahan produced twenty‐one books, including eleven collections of essays, two naval biographies, two memoirs, and the famous Influence series that examined international history from 1660 to 1815. His histories emphasized the persistent nature of international conflict, particularly between great powers competing for access to trade and resources. His religion, research, and theorizing, as well as his experiences at the First Hague Conference for limiting warfare (1899), led him to believe that diplomacy was best engaged in after successful conclusion of the battle. For Mahan, international relations hinged on power projection. In the modern era, this was best exercised by navies.

Mahan identified three critical elements of seapower: (1) weapons of war, primarily battleships and their supply bases; (2) a near monopoly of seaborne commerce from which to draw wealth, manpower, and supplies; and (3) a string of colonies to support both of the above. His theories, however, rested on two serious fallacies. First, his overreliance upon the notion of concentrating forces falsely denied the importance of coastal defense, and undervalued commerce raiding. These assumptions forced strategists to search for a decisive, war‐winning battle, often in vain. Second, he overstated the strategic benefits of controlling seaborne commerce and colonies. Whereas in peacetime these components of empire frequently contributed to wealth and consequently to long‐term strength, in war they often proved to be liabilities. Mahan's timeless principles, as enacted along the lines of late‐nineteenth‐century navalism, had the effect of turning America's strategic vision of itself on its side; instead of remaining an unassailable continental power with maritime reach, it became an overstretched maritime power with global vulnerabilities.

From 1896 until his death, Mahan lived in New York City and at Quogue on Long Island with his wife and unmarried daughters. Though the value of his writings continues to be debated, of their influence on the navies of the United States and other countries there can be no doubt.
[See also Doctrine, Military; Sea Warfare; Strategy: Naval Warfare Strategy; Tactics: Naval Warfare Tactics.]


Robert Seager II and and Doris Maguire , The Letters and Papers of Alfred Thayer Mahan, 3 vols., 1975.
Robert Seager II , Alfred Thayer Mahan: The Man and His Letters, 1977.
John B. Hattendorf and and Lynn C. Hattendorf , A Bibliography of the Works of Alfred Thayer Mahan, 1986.
Kenneth J. Hagan , This People's Navy, 1991.
Mark Russell Shulman , Navalism and the Emergence of American Sea Power, 1882–1893, 1995.

Mark R. Shulman

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