Which navy officer's ideas on sea power shaped American naval strategy in the late 19th century?

• A. George Dewey
• B. Alfred Thayer Mahan
• C. David Farragut
• D. Chester Nimitz

Answer: (B)

Alfred Thayer Mahan argued that national power rests on sea power—having a strong, modern navy, protected sea lanes, and overseas bases to project force and defend trade. In the late 1800s his ideas encouraged the United States to build a bigger, steel-hulled fleet and to create a network of coaling stations and bases around the world. This shift made naval power central to U.S. strategy, helping justify expansion and the emphasis on overseas presence in the aftermath of the Spanish–American War. The other figures were important in naval history—Dewey as a key commander in 1898, Farragut as a Civil War hero, and Nimitz as a WWII leader—but they did not shape the period’s strategic doctrine in the way Mahan did.