Winner of the 2024 Samuel Eliot Morison Award for Naval Literature
The Neptune Factor is the biography of an idea—the concept of “Sea Power,” a term first coined by Capt. A.T. Mahan and the core thread of his life’s work. His central argument was that the outcome of rivalries on the seas have decisively shaped the course of modern history. Although Mahan’s scholarship has long been seen as foundational to all systematic study of naval power, Neptune Factor is the first attempt to explain how Mahan’s definition of sea power shifted over time.
Far from presenting sea power in terms of combat, as often thought, Mahan conceptualized it in terms of economics. Proceeding from the conviction that international trade carried across the world’s oceans was the single greatest driver of national wealth (and thus power) in history, Mahan explained sea power in terms of regulating access to ‘the common’ and influencing the flows of trans-oceanic trade. A nation possessing sea power could not only safeguard its own trade and that of its allies but might also endeavor to deny access to the common to its enemies and competitors.
A pioneering student of what is now referred to as the first era of globalization, lasting from the late nineteenth century until the First World War, Mahan also identified the growing dependence of national economies upon uninterrupted access to an interconnected global trading system. Put simply, access to ‘the common’ was essential to the economic and political stability of advanced societies. This growing dependence, Mahan thought, increased rather than decreased the potency of sea power.
Understanding the critical relationship between navies and international economics is not the only reason why Mahan’s ideas remain—or rather have once again become—so important. He wrote in, and of, a multi-polar world, when the reigning hegemon faced new challenges, and confusion and uncertainty reigned as the result of rapid technological change and profound social upheaval. Mahan believed that the U.S. Navy owed the American people a compelling explanation of why it deserved their support—and their money. His extensive, deeply informed, and highly sophisticated body of work on sea power constituted his attempt to supply such an explanation. Mahan remains as relevant—and needed—today as he was more than a century ago.
Industry Reviews
"Just when it starts to seem that after more than a hundred years there is nothing new to say about Alfred Thayer Mahan’s writings, along comes The Neptune Factor by Nicholas A. Lambert. In this newly published and detailed biography, Lambert provides a wholistic view that greatly expands the canon. Mahan’s understanding of geo-economic factors as well as his unique ability to write in such a way that his message was understood by the public as well as the military and political elite is a necessary perspective. Lambert’s work in researching and writing The Neptune Factor has provided us with a book that should be in the library of every military, diplomatic, and strategic scholar."—International Journal of Military History
"Nick Lambert’s new study of Alfred Thayer Mahan offers a fascinating and convincing series of arguments about a topic of clear relevance for today: sea power. Lambert continues, and perhaps has gone a long way toward finishing, the work done in revising our modern understanding of Mahan that was needed after a period of anti-Mahanian and misdirected scholarship."—Journal of Military History
"The Neptune Factor also highlights the need to integrate new concepts like cybersecurity, the use of space assets, and the deployment of underwater and surface maritime unmanned vehicles into our naval technology."—US Harbors
"Reports from various think tanks, other organizations, and media have warned of a maritime crisis for years. Their voices echo that of the patron saint of modern navalists, Alfred Thayer Mahan. In this environment, a timely new book revisits a century-old topic, enlightens readers with previously undiscovered research, and corrects misinterpretations. In reading the entirety of Mahan’s published works and discovering previously buried correspondence, Lambert resurrects the first American navalist in a way that challenges those who venerate him. This extraordinarily well-researched book outlines the need for a properly sized navy to support national goals and economic stability."—The National Interest
“The Neptune Factor is a rigorous and scholarly reassessment of Alfred Thayer Mahan’s work that challenges conventional interpretations and highlights the complexity of historical strategic thought. While the book may be, at times, too dense for casual readers, its insightful analysis is essential to understanding naval power’s role in global economics and strategic planning. Lambert’s work is a valuable resource for scholars and strategists, offering a deeper understanding of sea power’s historical and ongoing impact on international relations."—National Security Institute
“Often quoted but seldom read, Alfred Thayer Mahan is sometimes dismissed as little more than a pedantic and parochial advocate of big fleets and decisive naval battles. In this brilliant new intellectual biography, Nicholas Lambert demonstrates, to the contrary, that Mahan was actually a profound analyst of the strategic implications of globalization. Original, provocative, and compelling, Lambert’s book traces the evolution of Mahan’s thought and demonstrates its contemporary relevance. Essential reading for scholars, strategists, and naval officers alike.”—Prof. Aaron L. Friedberg, Princeton University, Author of Getting China Wrong and A Contest for Supremacy: China, America, and the Struggle for Mastery in Asia
"Although the title suggests a rather narrowly focused account, The Neptune Factor is a far-reaching reappraisal of Mahan and his interpreters from the 1890s to the present. Lambert’s insightful and readable book places Mahan’s
