The Shared Genius of Mahan and Corbett


Kevin D. McCranie, Mahan, Corbett, and the Foundations of Naval Strategic Thought (Naval Institute Press, 2021).

Strategists and writers examining naval affairs argue a lot: the necessary size of the fleet, its composition and design, the education or specialization of the officer corps and the sailors, and the relative integration of U.S. Navy and U.S. Marine Corps operations are all areas of discussion, debate, and development. However, there is one thing on which it seems all naval writers and thinkers agree: Somewhere in your article, you must quote either Alfred Thayer Mahan or Julian Corbett, but you cannot quote both. Today’s naval writing and thinking casts the two founding fathers of modern naval thought as competitors, as men who have diametrically opposed ideas and who created “schools” of naval thought. As a result, you must pick one or the other as your guiding star.



Articles in the pages of the leading naval journals include titles like “Going to War with China? Ignore Corbett. Dust Off Mahan!” and “Going to War With China? Dust Off Corbett!” Even here at War on the Rocks, authors are not immune, telling us that “it may be time to demote Mahan’s masterpiece to the second rung, in favor of paying increased attention to Julian Corbett.” This conception of Mahan and Corbett, as strategists, thinkers, and writers in competition, is not only ahistorical — it is astrategic. Kevin McCranie’s masterful new book Mahan, Corbett, and the Foundations of Naval Strategic Thought attacks misperceptions, misreadings, and misunderstandings of the two men and their writing head on. He gives us a clearer understanding of their ideas and their views on strategy and naval warfare. In reality, Mahan and Corbett largely agreed with one another, and reading their work in tandem offers a single school of strategic thought, a school of maritime power.

A Fresh Look at Classical Naval Strategy

Misreadings and misinterpretations of Mahan and Corbett are as common as clear understanding today. Even experienced national security commentators get things wrong. In a recent article entitled “Mahan’s Illusory Command of the Seas,” Harlan Ullman makes several faulty assertions that can be cleared up by reading McCranie’s book. The claim that Mahan believed in the concept of a total and absolute command of the seas is a common one. But in his chapter entitled “Command of the Sea,” McCranie dives deeply into the writings of both Mahan and Corbett to determine what they meant by the phrase. While both strategists seemed to see total and absolute command as an ideal, neither really thought that it was always realistically attainable in a practical sense. Corbett was the clearest in his writing on the gradations of command, in a temporally or geographically limited reality. However, Mahan was just as suspicious of a navy’s ability to achieve total command. When today’s writers talk about Mahan, they often quote him as saying that seapower and command of the sea “is the possession of that overbearing power on the sea which drives the enemy’s flag from it,” but they often skip the very next clause in the same sentence “or allows it to appear only as a fugitive,” which suggests that Mahan did not see command as total and absolute. McCranie suggests that in reading the two men together, “command is less about control of the sea than about relative dominance.”

Each chapter of this book fires a salvo into false impressions of or caricatured teachings on the two strategists. Some of our contemporary naval commentators suggest that Corbett did not understand or account for economics enough in his writing. But McCranie shows that economics and seaborne trade were clearly on Corbett’s mind and a part of his naval thinking. Today’s naval articles often decry Mahan’s focus on “decisive” battles and hold it up as an example of how incomplete his thinking was. However, McCranie reveals that Corbett also placed fleet-on-fleet battle at the top of the naval priorities list. Additionally, Mahan did not use the word decisive in the way that we do today, using it to suggest a kind of indispensable nature rather than to indicate something that outright ended a war. The Battle of Trafalgar was decisive, in Mahan’s usage, not because the war ended in 1805 (it clearly did not) but because Adm. Horatio Nelson’s victory resulted in general command of the sea for Great Britain that ensured eventual victory. Trafalgar allowed for the necessary and secure seaborne logistical support of the Peninsular War and the strangling of the continent’s economy, and thus Mahan saw sea power as the decisive element that led to Napoleon’s downfall. Despite this, Mahan himself wrote that the sinking of ships and winning of sea battles “is itself only a means, not an end, and the two cannot be confounded.”

McCranie dove deep into the documentary record, perhaps deeper than anyone before. He tackled the published work of the two men, which is a daunting task in itself with over 40 books and several hundred articles and essays between them. He also mined Mahan’s voluminous correspondence and Corbett’s nearly daily diary entries to deepen his understanding of their arguments and how they explained them. Many writers have a tendency to rely on favorite quotes from either of the men, or a reading of one or two sources from them. McCranie tackles the question of the relationship between Mahan and Corbett, however, not only in width but in the deepest depth. The result is that when a section of published writing introduces the potential for confusion (more often the case in Mahan’s writing than Corbett’s), McCranie has multiple resources for finding clarifications, rather than simply relying on his own analysis or supposition.

After studying each strategist’s views of the uses of history and theory, the comparisons of offense and defense, the relative importance and value of concentration, sea denial, and joint expeditionary warfare, McCranie repeatedly comes to a parallel conclusion. He tells the reader that “similarities dominate when Corbett’s naval strategy is compared with Mahan’s. Though the two often took different routes to their determinations, their theories are not polar opposites; rather they differ by degree.” The two men build on one another, clarify the ideas behind naval strategy, and add nuance to maritime thinking. “Arguably,” he tells us, “Mahan’s work was a necessary prerequisite to Corbett’s.” Much of Mahan’s work came first, and Corbett had the opportunity to read it and digest the ideas before putting his own pen to paper. Many of the foundational ideas that Mahan expressed, but did not always provide clear detail for or develop analytically, Corbett returned to and fleshed out in more depth. The two men clearly had their differences and occasional disagreements, but when compared to their agreements and the grand scheme of their thinking on sea power these differences added nuance and offer today’s readers curious questions to ponder rather than shaping the two men as counters to one another.

The Danger of Competing Schools

Mahan abhorred doctrinaire approaches to naval strategy. He insisted that strategy was an art, not a science, where deviations from the rules were what made genius. Corbett wrote that, despite the effort that he and Mahan made at deriving principles of naval strategy, “every case will assuredly depart from the normal to a greater or lesser extent, and it is equally certain that the greatest successes in war have been the boldest departures from the normal.” And this is why breaking “Mahanian thought” or “Corbettian strategy” into competing schools is so dangerous.

When today’s war college and staff college instructors, or naval writers and modern maritime strategists, leave students and readers with the idea that they have to pick and either follow Mahan or follow Corbett, they reduce the thinking element of naval strategy. Naval culture is dominated by the technological mindset and engineering-based thinking, what is often called the material school by historians. This looks for procedures, doctrines, and set methods that can be duplicated in the face of naval challenges. Casting Mahan or Corbett as the progenitors of schools with doctrines to be followed in lock step makes them seem more approachable to this way of thinking, but fundamentally reduces the value of their work and eliminates the very thing that they both insisted on: critical thinking and looking for the right moment to deviate from set procedure or doctrine. Neither man tolerated dogma or maxims. In their wide writings they suggest that we have to understand doctrine not because we should be following it, but because we need to be creative enough to know when to violate it.

Instead of a competition, we need to be reading what Mahan and Corbett wrote as complementary. These are the two sides of the coin of maritime power. The places in which they disagree, or where their analysis leads them to focus on different ways of looking at a similar question, are places to pay special attention. This is not because we should always pick one side or the other, but because these differences offer today’s strategist a place to pick their head up out of the book and look around. A chance to consider the details of our own time, the specifics and geopolitics of our contemporary challenges, and the changes to the character of war created by modern weapons or technologies, and thus to make a strategic decision based in the present rather than one bound tightly with one or another of the naval thinkers of the past. While both Corbett and Mahan wrote on naval strategy, and offered up theories and principles, both men were also naval educators. More than anything else, their aim was to create thinking, critical, informed decision-makers who could operate in their present and make sound military and maritime conclusions in their contemporary world.

The Foundations of Naval Genius

Mahan, Corbett, and the Foundations of Naval Strategic Thought is not the end of the discussion on Mahan and Corbett. McCranie has written an excellent examination of the two men, their work, and how they viewed naval strategy. His focus on developing a “way of war” for each of the historian-strategists, however, has left a part of their writing and thinking behind. Both men wrote on naval professionalism, naval organization, and command in addition to wartime strategy. Mahan, in particular, wrote a great deal on international relations and what today we would call “grand strategy,” in books like The Problem of Asia and Its Effect Upon International Politics and essays collected in The Interest of America in Sea Power, Present and Future. This work resulted in the historian Jon Sumida crediting him with “inventing grand strategy.” But those elements of their writings were not the purpose of McCranie’s book and pointing out other areas for examination does nothing to take away from what he has accomplished. His book should become the starting point for all discussion of Mahan and Corbett, and especially for comparisons between the two, in the future.

In his recent article “Classic Works on Sea Power Have Enduring Value,” John Maurer made the case that, despite being a century old and from an earlier technological era, “both authors belong on the reading list of those who consider themselves strategic leaders.” Mahan and Corbett without a doubt provide the “foundations” of naval strategic thought. Combined with the writings of the men themselves, and a few other books like Sumida’s Inventing Grand Strategy and Teaching Command and Andrew Lambert’s 21st Century Corbett: Maritime Strategy and Naval Policy for the Modern Era, McCranie’s work can launch current and future naval leaders toward the mastery of the principles of naval strategy and the genius to know when to break the rules. Reinforcing the value of critical thinking, an understanding of history, and an appreciation of the use and abuse of theory in naval affairs, comprehending the depth and breadth of the work of the two great naval historian-strategists will continue to prepare naval strategists for the present and the future.



BJ Armstrong is a contributing editor with War on the Rocks and holds a Ph.D. in war studies from King’s College London. He teaches naval and maritime history at the U.S. Naval Academy and his fourth book, Developing the Naval Mind, coauthored with John Freymann, is forthcoming in November 2021. Opinions expressed in his article are offered in his personal and academic capacity, and do not reflect the positions or policies of the U.S. Naval Academy, the Department of Defense, or any other agency.

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