Final answer:
Admiral Alfred T. Mahan advocated for a stronger navy and enhanced sea power to assure national greatness, economic prosperity, and global competitiveness, influencing America's naval expansion and policy makers like Theodore Roosevelt.
Step-by-step explanation:
Admiral Alfred T. Mahan argued for a stronger navy and greater sea power because he believed that naval strength was essential to a nation's greatness and prosperity. According to his landmark work, The Influence of Sea Power upon History, 1660-1783, published in 1890, a powerful navy was critical to protecting commercial interests, ensuring a productive industrial economy, and maintaining a fleet engaged in international trade. Mahan advocated for faster battleships, global coaling stations for refueling, and strategic military bases in the Caribbean and the Pacific to solidify America's competitive position in the global arena and prevail in conflicts such as the Spanish-American War.
Mahan's principles also included the construction of big ships with big guns, and the acquisition of territories like Hawaii and the Midway Islands for strategic positions and coaling stations, which were imperative because of the limited reach of steamships at the time. His ideas about expanding and modernizing the US fleet heavily influenced policymakers, including Theodore Roosevelt, and contributed to America's rise as a naval power by the end of the 1890s, ranking third in the world.