This article analyses the lasting influence of US Admiral Alfred Thayer Mahan’s theories on sea power and hydropolitics as a critical factor in geopolitical equations. Mahan, a scholar of military history who advocated the pursuit of global oceanic supremacy for the US, was widely read. He inspired not only his own country but Germany as well, which sought to gain naval superiority in the first half of the twentieth century. Today, China is following Mahan’s advice by building a blue water navy and extending its maritime domain across the three island chains that ring the China Sea and the Western Pacific, thereby challenging American maritime dominance and US allies in the Pacific and Indian oceans.
