Alfred Thayer Mahan

Captain Alfred Thayer Mahan (1840-1914) was a United States Navy flag officer, geostrategist, and historian, who has been called "the most important American strategist of the nineteenth century." His concept of "sea power" was based on the idea that the most powerful navy will control the globe. The concept had an enormous influence in shaping the strategic thought of navies across the world, especially in the United States, Germany, Japan and Britain. His ideas still permeate the U.S. Navy.

He was born at West Point, New York and attended Saint James School, an Episcopal college preparatory academy in western Maryland and then studied at Columbia for two years before, against his parents' wishes, transferring to the Naval Academy, where he graduated second in his class in 1859.Commissioned as a Lieutenant in 1861, he served the Union in the American Civil War as an officer on USS Worcester, Congress, Pocahontas, and James Adger, and as an instructor at the Naval Academy. In 1865 he was promoted to Lieutenant Commander, and then to Commander (1872), and Captain (1885). As commander of the USS Wachusett he was stationed at Callao, Peru, protecting American interests during the final stages of the War of the Pacific.

Despite his professed success in the Navy, his skills in actual command of a ship were not exemplary, and a number of vessels under his command were involved in collisions, with both moving and stationary objects. He had an affection for old square-rigged vessels, and did not like smoky, noisy steamships of his time; he tried to avoid active sea duty.In 1885, he was appointed lecturer in naval history and tactics at the Naval War College.

Mahan wrote more than a hundred articles on international politics and related topics, which were closely read by policy makers.

His views were shaped by the seventeenth century conflicts between Holland, England, France and Spain, and by the nineteenth century naval wars between France and Britain, where British naval superiority eventually defeated France, consistently preventing invasion and blockade. To a modern reader, the emphasis on controlling seaborne commerce is commonplace, but in the nineteenth century, the notion was radical, especially in a nation entirely obsessed with expansion on to the continent's western land. On the other hand, Mahan's emphasis of sea power as the crucial fact behind Britain's ascension neglected the well-documented roles of diplomacy and armies; Mahan's theories could not explain the success of terrestrial empires, such as Bismarckian Germany. However, as the Royal Navy's blockade of the German Empire was a critical direct and indirect factor in the eventual German collapse, Mahan's theories were vindicated by the First World War.