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.
While Book III is clearly incomplete, with author’s notes sketched on sections inserted by the translators (Messrs. Howard and Paret), the later chapters (each barely a page in length) have strong sinews of content that are deserving of attention – and remain relevant even today.
For instance, in describing the “Elements of Strategy”, Clausewitz presents a list of strategic elements that shape engagements: moral, physical, mathematical, geographical, and statistical. While his logic is not a plainly evident as in Book I, his conclusions are striking: do not treat these elements in isolation, since their interrelationships are intricate and complex. “A dreary analytical labyrinth would result, a nightmare in which one tried in vain to bridge the gulf between this abstract basis and the facts of life.” And in one paragraph, Clausewitz shatters the tenuous intellectual foundations of Effects-Based Operations (EBO) and Operational Net Assessment (ONA).
He continues to note the “incredible effect” of moral factors in deciding engagements, and notes that all three principal elements (skill of the commander, experience and courage of the troops, and their patriotic spirit) must be treated as one – not independently.
After a chapter describing the military virtues of the army, he returns to the character and nature of the individual: lauding “boldness” as never detrimental, the essential nature of “perseverance”, and surprisingly expounds for several pages on the importance of “superiority in numbers” (which he concludes, thankfully, by noting “it would be seriously misunderstanding our argument, to consider numerical superiority as indispensible to victory…”).
While “surprise” is noted as an important objective for the commander, Clausewitz dismisses “cunning” as a quality that “ … do[es] not figure prominently in the nature of war.” His concluding chapters (on geometric forces, reserves, economy of force and suspension of hostilities) are the fundamentals of blocking and tackling for warfare. But it is in between these respective sections that Clausewitz’s incomplete tome has a true gem: the successive chapters on “Concentration of Forces in Space” (Chapter 11) and “Unification of Forces in Time” (Chapter 12).
By returning to the notion of spacetime, Clausewitz binds the often-dueling nature of strategy and tactics into a useful guide for the commander. While initially dismissive of “splitting” forces (an act that Bobby Lee did not just once, but twice – in the face of a numerically-superior foe – at the Battle of Chancellorsville in 1863), Clausewitz notes that such acts should be justified. Otherwise, they should remain concentrated in space. Adding the metric of time, Clausewitz continues that too great a force in space will be at a disadvantage in time – not only through a greater target density, but also through increased confusion and disarray.
Here, Clausewitz arrives at “a vital difference between strategy and tactics”: that tactical success occurs during the phase of disarray and weakness, while strategic success already lies beyond that phase. “The consequence of this difference is that in the tactical realm force can be used successively, while strategy knows only the simultaneous use of force.” (Emphasis added.)
Therefore, while time (e.g., duration) can be a detriment tactically, the unification of forces in space with those in time mitigate the destructive efforts on the forces involved. For the strategist, “all forces intended and available for a strategic purpose should be applied simultaneously; their employment will be the more effective the more everything can be concentrated in a single action at a single moment.” It is very likely in these passages that Herman Kahn, the noted U.S. nuclear strategist who penned On Thermonuclear War, derived the reasoning that led to the doctrine of Mutually Assured Destruction (MAD).