Act 1856 to allow citizens to take unclaimed islands for the US and allow extraction of this resource. This is reflected in the historical and current insular territories of the United States. American expansionism and imperialism was influenced through this book as Theodore Roosevelt wrote to Mahan: "during the last two days I have spent half my time, busy as I am, in reading your book ... I am greatly in error if it does not become a naval classic". There is noted influence on reading this book and Roosevelt's push to start expansionism with the Spanish-American War to secure resources and naval "highways" for ships across the Caribbean and Pacific – later influencing their ability to operate airstrips for World War I and World War II in places such as Guam. 21st century Mahan's strategic theories continue to be influential into the 21st century, especially in the newly emerging naval powers India and China. Although Mahan's influence on foreign powers has been widely recognized, only in recent decades have scholars called attention to his role as significant in the growth of American overseas possessions, the rise of the new American navy, and the adoption of the strategic principles upon which it operated. See also Alfred Thayer Mahan History of the Royal Navy (after 1707), British navy Naval warfare US Navy Notes References Further reading Apt, Benjamin. (2004). "Mahan's Forebears: The Debate over Maritime Strategy, 1868–1883." Naval War College Review. 50(3): 86–111. Shulman, Mark Russell. (1991). "The Influence of Mahan upon Sea Power". Reviews in American History. 19(4): 522–527. Shulman, Mark Russell. (1995). Navalism and the Emergence of American Sea Powers, 1882–1893. (1st ed.) Annapolis: Naval Institute Press. External links Mahan and The Influence of Sea Power Upon History Project Gutenberg e-text Internet Archive scan of first edition held by UCLA 13th edition (1918) via HathiTrust 1890 non-fiction books Books of naval history