Why did alfred thayer mahan think thag a large and more powerful navy would american expansion

In 1890, Captain Alfred Thayer Mahan, a lecturer in naval history and the president of the United States Naval War College, published The Influence of Sea Power upon History, 1660–1783, a revolutionary analysis of the importance of naval power as a factor in the rise of the British Empire. Two years later, he completed a supplementary volume, The Influence of Sea Power upon the French Revolution and Empire, 1793–1812.
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