DECODING CLAUSEWITZ, Jon Tetsuro Sumida, University Press of Kansas, Lawrence, 2008, 234 pages, $29.95.

Reviewed by LTC James E. Varner, USA, Retired, Fort Leavenworth, Kansas
Military Review (Jan-Feb. 2009), pp. 119-120

FM 3-0, Operations, cites only three sources for the manual: Arthur Bryant’s biography on the Duke of Wellington; a 2007 speech by Secretary of Defense Robert Gates; and the 1976 edition of Carl Clausewitz’s On War. The first two sources appear in the manual only once, while Clausewitz is quoted repeatedly in topics ranging from chaos, chance, and friction to centers of gravity and operational reach. Few would dispute the fact that Clausewitz has influenced American military doctrine for the last 30 years, but do those who read his book really understand the messages the Prussian theorist intended to convey? In Decoding Clausewitz, Jon Tetsuro Sumida suggests that they often do not.

Sumida dedicates an entire chapter to military theorists and their relationships with Clausewitz; his research is revealing and insightful. He provides an informative analysis of Antoine Jomini’s “dismissal” of Clausewitz as well as Basil Liddell Hart’s “repudiation” of the Prussian thinker. The section dedicated to Jomini, a contemporary of Clausewitz, is of particular interest because Sumida provides a clear account of each theorist’s critique of the other. Clausewitz’s well-known attacks on his predecessors and contemporaries for “arbitrary notions” and “bogus theorizing” are found in chapter six of On War. Sumida provides a helpful survey of previous scholarship by detailing Jomini’s assessment of On War, which he said contained “defective reasoning” and “pretentious and pedantic” style. Sumida’s discussion of each theorist’s position on guerrilla war is particularly enlightening and timely today.

Liddell Hart was quite critical of Clausewitz as well. An advocate of victory by using maneuver to “dislocate and demoralize” the enemy, he claimed Clausewitz’s endorsement of Napoleonic tactics and his fascination with “maximizing violence to fight and destroy the enemy’s main army” greatly influenced many World War I leaders (Foch, Ludendorff, Schlieffen), thus contributing to the war’s extreme brutality. Sumida is even-handed and analytical in his discussion, challenging both Jomini’s and Hart’s misreading of Clausewitz when necessary.

Sumida follows his chapter on theorists with one focused primarily on the vast amount of scholarly research dedicated to Clausewitz since 1976. Throughout the chapter, Sumida acknowledges the work of several scholars, but in the end, he determines that “none of these thinkers [Aron, Paret, Gallie] achieved complete command of On War.” He develops his argument by providing biographical information on each scholar and a brief summary of his main points, and then compelling analysis why each man’s conclusions were unreasonable. Some may find the focus on philosophy disconcerting. For example, Sumida’s references and discussion of Clausewitz in terms of Hegel’s dialectical reasoning reinforce the book’s ongoing philosophical bent. Is this book for philosophers, military men, or that very small group who are both?

Developing competent generals was important to Clausewitz because success in that pursuit could ensure the existence of Prussia. He criticized “using principles derived from history as the basis of officer education,” which he saw as role-playing. Instead, he proposed historical reenactment, which would presumably reproduce both the emotional and intellectual “difficulties of supreme command.” Sumida’s discussion of the differences between reenacting and role-playing in the development of military leaders is tough reading; it comes across as pure philosophy, in many ways as dense and ponderous as Plato’s Allegory of the Cave. Some military professionals might find themselves wondering whether such musing interferes with the production of an operations order.

Sumida’s title, Decoding Clausewitz, implies that Clausewitz is not well understood by those who read his work. In his introduction, Sumida admits that there is no consensus as to what On War means, which is in itself cause for concern. To further add to the confusion, Sumida concludes that Clausewitz, “like Ludwig Wittgenstein a century later, believes that words can convey little more than a crude approximation of any complex and difficult reality, especially when a large part of experiencing that reality involves the play of emotion.” Sumida hints that the imprecision of language prevents us from ever fully communicating because none of us defines words in the same way, and thus we can never capture truly complex concepts.

Questions arise. If Clausewitz’s writing is accessible to a general audience, why does it need to be decoded? On the other hand, if On War is really so cryptic that it requires special insight from a small coterie of the cognoscenti to be accessible, how is it of any use to military professionals? What does the military community know to be true, and is such information agreed upon? Worse, what are the implications if we really do not know what Clausewitz meant?

Sumida sees On War as the philosophy of a practice rather than a philosophy about the essence of a thing, a distinction that requires some work to grasp, perhaps more effort than many are willing to expend. This book is philosophy about philosophy, often a challenging read.