Clausewitz, On War, Book IV: The Rise and Fall of Battle

Book IV is entitled: The Engagement. It has, to a large degree, been surpassed by later developments. Clausewitz saw that in his own day, warfare had moved from the smaller scale, more limited scope wars of the 18th Century, to the full-scale, nation-in-arms, all-out warfare of the Revolutionary and Napoleonic eras. To Clausewitz, the lesson that had been beaten into his head, by the hard lessons of a life spent at war, was that war would not and could not go back to its earlier more limited form.

What did Clausewitz glimpse behind these vast transformations, this new way of war that ate up whole armies, crushed major powers into the dirt, and hacked a swath of destruction across the continent? He saw the face of the God of War himself. Behind the ephemera, however titanic, fiery, bloody — and hence distracting — was the rock-like simplicity of Absolute War. It was not possible to reach the level of Absolute War in reality. But it was the gravitational center toward which war tended. And in an age when earlier limits, which had seemed to be the order of nature, were blown to bits, the nearest approximation of Absolute War was a major battle, an engagement in which the mass of two nation’s armies were pitted against each other, at a unitary place and time, and there slugged it out, consuming men and wearing each other down, until one army had its spirit broken, and began to fall back, and could then be pursued to destruction. “What is the battle? It is the engagement by the main force … the battle must be considered as the true center of gravity of the war.” Battle was the epitome of war in the modern age, as Clausewitz had seen with his own eyes. He experienced the losing side at Jena: (“Those who have never been through a serious defeat will naturally find it hard to form a vivid and thus altogether true picture of it.”) He experienced the victorious side at Waterloo.

He was generally right about the centrality of battle for just over 100 years, from his death until 1945. Not bad at all. Better than most explanatory models outside of the physical sciences.

Major European powers in the era 1789-1945 hurled their armies directly against each other, bashing their skulls against each other. They sought to mass themselves for a decisive, war-deciding victory in battle, for the knockout punch. The Wars of German Unification fell into this pattern. The Austro-Prussian war was decided at the Battle of Königgrätz. The Franco-Prussian War was decided at the Battle of Sedan. Clausewitz’s heirs validated his theory in blood and iron. But changes in technology began to trend against the single, knock-out blow.

Clausewitz described a typical battle in his day:

The troops move calmly into position in great masses deployed in line and in depth. Only a relatively small proportion is involved and left to conduct the firefight … . [T]he fighting [sways] to some extent to and fro. Gradually, the units are burned out and when nothing is left but cinders, they are withdrawn and others take their place.

In World War I, this process did not last for one day, but for years. World War I, in the West, due to many factors, ended up, in effect, as a single gigantic, interminable engagement. Whole populations and whole economies were fed into the firing line and consumed, burned out, reduced to cinders.

Nonetheless, if World War I seemed to be the partial demise of Clausewitzian Battle, World War II was a spectacular (and by many, unexpected) return engagement — please pardon the pun.

World War II saw the return of mobility, and hence the return of decisiveness, and hence the utility of battle to achieve strategic aims beyond just shoveling lives and treasure onto the bonfire. We need only think of the gigantic battles in 1942-43 at Stalingrad, in 1943 at Kursk, in Poland in 1944 (a battle so huge it is sometimes referred to simply as “the Destruction of Army Group Center”) and finally the Wagnerian Apocalypse of the capture of Berlin in 1945. These vast struggles were beyond any scale Clausewitz could have imagined in terms of time, space, numbers and technology. Yet they were nonetheless nothing if not “engagements” in the precise sense of Clausewitz’s Book IV.

1945 brought the advent of nuclear weapons and began a period of increasing peace, or at least indirect and lower level conflict, between the major powers. The culmination of war in a massive engagement became increasingly uncommon and has been fading away ever since. The gigantic Red Army panzerblitz through the Fulda Gap was played out with cardboard counters on hexagon maps countless times but, thanks be to God, never in reality. That would have been a Super-Kursk on a scale that would have made Mars himself themselves turn away in horror, to say nothing of the nuclear crescendo which would probably have brought the drama to a close.

Clausewitz, in Chapter Two, as he so often does, tells that his whole discussion of battle is subject to change:

Contemporary armies have developed almost identically in military organization and methods; the element of war itself, stirred up by great national interests, has become dominant and is pursuing its natural course. Battles will not change their character so long as both these conditions hold good.

This is precisely what happened. The conditions no longer “held good”. The “contemporary armies” that were in conflict came increasingly to not be similar European armies fighting against each other. Rather, it was European or American or Russian/Soviet armies fighting against people from other places, with different “organization and methods”. Further the “great national interest” of these countries became, foremost, not going up in a cloud of radioactive smoke, secondarily enjoying the leisure provided by modern technology. So, these “civilized” militaries either withered away entirely, or fought wars of choice against less wealthy adversaries from less valuable, poorer, dirtier places. These “backward” opponents had the disadvantage of poverty and hence a lack of spiffy, shiny new weapons. But they had instead the inestimable advantage of having “great national interests” at stake. America could always “come home” from Vietnam, the French from Algeria, the Russians from Afghanistan. Their opponents were already at home. They either won or died. And they, unlike their opponents, could draw on national, political, ideological and religious ideals that made them fervent and committed opponents. These “advanced” armies had been built to fight and win “engagements”. There was, after all, the Red Army to worry about — or for the Russians, there were NATO and China. Yet, the apparent superiority of the “First World” army with its helicopters and armored vehicles and jet aircraft is an illusion that Clausewitz could have easily pointed out. The mismatch was really the other way, and resided in the will of the people, the tenacity and focus of the political leadership, and the ruthlessness and creativity of the military leadership. After all, Clausewitz told us that the moral far exceeds the physical in importance in war. (Throw in the assistance of one Cold War power or the other as a supplier and financier for the insurgent, of course. But weapons without will are mere hunks of metal.)

More directly, Clausewitz has already shown us that an army may win by avoiding an engagement and yielding ground, and allowing its enemy to consume itself and be ground down by harassment and harrying, as the Russians did, by retreating deep into Russia. He also told us that a people in arms, not even a proper army at all, such as the rebellion that arose in Spain, can grind down and splinter even a weapon of the Excalibur-like perfection of the Grande Armée.

This sort of war was a mismatch made in Hell for the armies sent to fight and bleed in these places.

So, the centrality of the engagement to the resolution of war, and thus to strategy, was perceived absolutely correctly by Clausewitz in his time and place. And he wisely also left open the prospect that, at other times and in other places, other means might come predominate as the decisive factor.

Yet, despite Clausewitz’s inevitable caveat, he is nonetheless very, very forceful in his statement that the war is waged by fighting, that the engagement is the way to destroy the enemy’s army, which in turn is the way to win the war. He has page after page of this. Why didn’t he hedge this more, make more of other alternatives? We expect omniscience from Clausewitz, after all, however unfairly. He is our oracle and sage of war. Almost two centuries later, under very different conditions, we see the world very differently. But, he had his reasons — sound ones.

Clausewitz feared that the Prussian army would regress back to the methods and mindset that preceded the era of Revolutionary and Napoleonic war. The 26 years from 1789 to 1815 could have been dismissed as exceptional, almost an accident, and not to be repeated. In fact, that was exactly what was happening in Prussia. The nation in arms was perceived as a threat by the political leadership, and the switch back to a smaller, strictly professional army was the order of the day. The military reformers were shunted off to posts where they would be unable to cause too much trouble. Clausewitz must have been driven mad with frustration.

So, Clausewitz was not writing about the critical nature of large-scale, mass battle solely to theorize, or even to educate, in any passive sort of way. He was the watchman at the gate, pounding on the alarm bell: Stop, look, think! This is not some aberration! Bonaparte was not a comet that crosses the sky once; he was the prophet of a new age! These wars we have just endured, which we barely survived, which killed so many of our friends, these were modern war as it actually is, as it will continue to be! The old world is dead!

American officers say, “no more Vietnams”.

Clausewitz was saying “no more Jenas”.

Clausewitz was facing the frustration of every generation of relatively young military reformers in the aftermath of a war. The senior leadership grew up before the war, and perceives that earlier world as “normal”. They want to get back to it. They are not always entirely wrong to want to do so. The younger officers, who grew up with the war, see the war experience as setting their profession, and the future of warfare, on a new course. The younger, reforming generation usually has our sympathy, looking back, because they were usually more correct, because the last few centuries have been an era of rapid change. The reformers’ vice is that they usualy overstate their case.

This is one of the many patterns we see recurring in military history.

The current debate within the US Army, between COIN advocates and those who are struggling to maintain a focus on high intensity kinetic warfare, with a de-emphasis on the experience of Iraq and Afghanistan, will be obvious to most of our readers.

One of Clausewitz’s famous quotes (pretty closely) applies here:

The fact that slaughter is a horrifying spectacle must make us take war more seriously, but not provide an excuse for gradually blunting our swords in the name of humanity. Sooner or later, someone will come along with a sharp sword and hack off our arms.

Thus the proponents of high intensity kinetic warfare might speak dismissively of what has been referred to as “armed social work”. There is merit on both sides of that debate, however heated the invective may get, and I think a split-the-baby resolution will ultimately happen.

There are many other things of interest in Book IV. I will note a few points.

Clausewitz again emphasizes that simple plans are necessary in war, and almost always superior to complex ones. He notes that courage is superior to intelligence, because danger is the essence of war. He notes that a commander cannot learn the most important things about war from books, and that an over-reliance on book-learning may lead to a formulaic approach to war, which is always bad.

These are threads that are woven through the whole book.

He notes in Chapter Six, the Duration of the Engagement, that:

The decision can never be reached too soon to suit the victor, nor delayed long enough to suit the loser. A victory is greater for having been gained quickly; defeat is compensated for by having been long postponed.

He also states that:

As a rule, shrinking from a major decision by evading such a battle carries its own punishment.

We can see in this the germ of modern practice by guerilla and insurgent forces. Delay and protraction favor these forces. They can never “win” an outright encounter, let alone a full scale battle. But they can leech the life out of any apparent victory by protracting the struggle and simply avoiding defeat. To do so they must suffer the consequences of avoiding battle, such as subjecting their civil populations to the unopposed actions of the enemy. George Washington, Mao Zedong and Vo Nguyen Giap all knew this, and acted accordingly, wearing down the enemy, aiming at political rather than strictly military results, until circumstances made it possible to strike more direct blows.

One of Clausewitz’s many aphorisms is rather buried in Chapter 10: “All war presupposes human weakness and seeks to exploit it.” Again, this seems to take on a larger meaning in our era when there are more ways to gain moral ascendancy over an opponent than by defeating him in a major battle. Getting a majority of young, attractive women to put flowers in rifle barrels, and to show contempt for courage and sacrifice and uniforms, will demolish the moral foundations of an army even if it never suffers a serious defeat on the battlefield, for example.

He also stated that

If major action fails to develop it is because outside factors have appeared, modifying and restraining the original animosity, and weakening, altering, or halting any movements.

While he meant this within the context of an ongoing war, the “outside factor” of nuclear weapons has certainly had all these effects in fact, remarkably, precisely these effects. This is another one of those brilliant beams of light that shine forth from the book, lighting up events centuries later.

Chapter Fourteen regards Night Operations. Some of the discussion is obsolete, pertaining to militar practices that no longer exist. Nonetheless, several passages in this chapter reminded me of modern guerilla and insurgent operations. First, a decisive battle cannot be fought at night, according to Clausewitz, thus “a night attack is only an intensified raid”. Of course, the US military now possesses night fighting capability. (Soon our enemies will have it as well, in the inevitable course of diffusion of military equipment and technique.) But for most of history, and for much of the world today, Clausewitz’s discussion of night operations holds true. The nature of a night attack is such that it “cannot be used against the whole of the enemy’s forces”. But where the entire purpose of the insurgent is to avoid contact with the enemy’s main force, raiding and picking away at outposts is precisely the method that he will want to employ. As Clausewitz notes, night actions are most appropriate for small detachments, and are “generally aimed at single outposts”. He mentions four conditions under which night operations are appropriate, one of which is “desperate situations in which one’s troops are so heavily outnumbered that only the utmost daring offers any prospect of success.” The insurgent or guerilla is in this situation as a matter of course. However, Clausewitz missed something that 20th Century experienc has shown. The victor in an insurgency is often not the one displaying “utmost daring” but rather “utmost patience” and meticulous preparation. The guerilla rules the night, or wants to, because he has no other choice. He must live by stealth and guile, and he has no hope of ruling the day.

This passage foreshadows the many insights that await in Book VI, entitled Defense. Much of the discussion in that book pertains to fortresses and terrain, and the details are largely obsolete as far as “conventional” operations are concerned. Nonetheless, I think much of it still has value for the insurgent and counter-insurgent warrior.

But first, on to Book V … .