The most ambitious of all eight books in On War, Book VI is more than triple the length of the other books equally any three of them in sheer volume. In this book, entitled simply “Defense”, Clausewitz offers practical lessons for the 19th century warfighter: operations on a flank (with diagrams), defensive mountain warfare, entrenched positions, and prescient of France’s Maginot Line of the early 20th century the importance of a network of interlaced cordons to a nation’s security.
Shane
Clausewitz, On War, Book V: Jointness à la Carl
Book V, entitled “Military Forces”, is a prescriptive summary of the “… conditions necessary to military action,” the maintenance and leadership of the three military branches contemporary to Clausewitz’s day: Infantry, Cavalry and Artillery. Many of Clausewitz’s edicts could just as easily apply to Ground, Air and Naval forces in our modern age.
Throughout Book V, Clausewitz makes note of the evolution of conflict from barely a century prior: the interrelated nature of distinct “Theaters of Operation” to a politically-driven war effort, the diminished need for “… long fixed periods in winter quarters” that would halt an operational tempo for months, and how (when combating forces are nearly equal in strength) the most creative and innovative commander will triumph.
Clausewitz, On War, Book IV: Attrition Writ Large
In his fourth book of On War, Clausewitz “ … now turn[s] to the essential military activity, fighting.” Following the same logical construct as Books I and II, where he first defines something then elaborates on its nature, Clausewitz gives us a description of “the nature of battle today” before providing general truisms of “the engagement”.
It is in Book IV that we see how dated some portions of On War have become. For instance, when describing “the nature of battle ‘today’” (i.e., in the early 19th century, shortly after the Congress of Vienna concluded the Napoleonic Wars), Clausewitz opines that “[d]arkness brings it to a halt: no one can see, and no one cares to trust himself to chance.”
Clausewitz, On War, Book III: The Substance of Strategy
After laying the definitional framework of war in Books I and II, Clausewitz now drills deep into the practice of strategy. His admonishments in Book III resonate today, and in fact are echoed by nearly every business management book on shelves today: to wit, “The strategist must go on campaign himself” (i.e., to allow adaptation to emerging conditions on a chaotic battlefield).
Careful to distinguish between strategy and tactics, Clausewitz underscores the temptation to deal with the present the “thousands of diversions” that can throw the execution of a well-formulated plan off course. His assertion that “… it takes more strength of will to make an important decision in strategy than in tactics” is particularly apt, especially since the tactician can observe “at least half the problem” empirically, while the strategist has to guess and presume.
Clausewitz, On War, Book II: Inducing a General Theory of War
In 1916, Albert Einstein published the General Theory of Relativity. As its name implies, the “general” theory was a broader ostensibly more strategic application of his Special Theory of Relativity from 1905. After starting with the descriptive, Einstein then broadened his perspective to induce a general theory that could be used to describe the nature of all universal forces.
Carl von Clausewitz followed this same path nearly a century earlier, first formulating his “Special Theory of War” in Book I a descriptive text that defined “what” war is before inducing a “General Theory” of how war applies across time and space.