Category Dupuy’s Verities

Dupuy’s Verities: Surprise

The Death of Paulus Aemilius at the Battle of Cannae by John Trumbell (1773). [Wikimedia]

The tenth of Trevor Dupuy’s Timeless Verities of Combat is:

Surprise substantially enhances combat power.

From Understanding War (1987):

Achieving surprise in combat has always been important. It is perhaps more important today than ever. Quantitative analysis of historical combat shows that surprise has increased the combat power of military forces in those engagements in which it was achieved. Surprise has proven to be the greatest of all combat multipliers. It may be the most important of the Principles of War; it is at least as important as Mass and Maneuver.

I have already written quite a bit on Dupuy’s conceptualization of surprise so I won’t go into it in detail here. These previous posts provide a summary:

The Combat Value of Surprise

Human Factors In Warfare: Surprise

Dupuy’s analysis focused on how surprise influenced combat power by enhancing the mobility and reducing the vulnerability of the side with surprise, and by increasing the vulnerability of the side that was surprised. In 2004, TDI undertook a study for the late Andy Marshall’s Office of the Secretary of Defense/Net Assessment to measure the historical combat value of situational awareness (more knowledge by one side than the other) and informational advantage (better knowledge by one side than the other) and how each of these factors related to surprise in combat. Chris Lawrence detailed this research and its conclusions in chapters 10 and 11 in his 2017 book, War by Numbers: Understanding Conventional Combat.

In general, the study found that both superior situational awareness and better information enhanced combat power, though perhaps not quite as much as inferred from the relevant literature. It also confirmed that surprise conferred an even greater combat power benefit, above and beyond that provided by battlefield awareness or informational advantages. It also suggested that the primary benefit of a situational or knowledge advantage in combat was not in achieving surprise over an enemy, but in preventing an opponent from achieving surprise itself.

These results, though quite suggestive, were tentative and more research is necessary. However, no follow on studies on this subject have been funded to date.

A Comment On The Importance Of Reserves In Combat

An German Army A7V near the Somme on March 26, 1918 [forces.net] Operation Michael was the first of a series of German Army offensives on the Western Front in the spring of 1918. In late March, 74 German divisions employing infiltration tactics created a breach in a sector of the line held by the British Army. The Germans advanced up to 40 miles and captured over 75,000 British soldiers, but the ability of the British and French to redeploy reserves via rail halted the offensive in early April short of strategic success.

In response to my previous post on Trevor Dupuy’s verity regarding the importance of depth and reserves for successful defense, a commenter posed the following question: “Is the importance of reserves mainly in its own right, or to mitigate the advantages of attacker surprise?”

The importance of reserves to both attacker and defender is as a hedge against the circumstantial uncertainties of combat. Reserves allow attacking and defending commanders the chance to maintain or regain initiative in response to the outcomes of battle. The side that commits its last reserves before its opponent does concedes the initiative to the enemy, probably irrevocably.

In Trevor Dupuy’s theory of combat, the intrinsic superiority of the defensive posture (as per Clausewitz) is the corollary to the attacker’s inherent advantage in initiative. When combined with the combat multipliers of favorable terrain and prepared positions or fortifications, the combat power of a defending force is greatly enhanced. This permits a defending commander to reap the benefit of economy of force to create reserves. When arrayed in sufficient depth to prevent an attacker from engaging them, reserves grant flexibility of response to the defender. A linear defense or improperly placed reserves concede this benefit to the attacker at the outset, permitting the attacking commander to exploit initiative to mass superior combat power at a decisive point without reserves to interfere.

A defender’s reserves are certainly useful in mitigating attacker surprise, but in Dupuy’s theories and models, surprise is a combat multiplier available to both attacker and defender. As perhaps the most powerful combat multiplier available on the battlefield, surprise in the form of a well-timed counterattack by a defender can devastate an attacking force. Even an unexpected tactical wrinkle by a defender can yield effective surprise.

Dupuy’s Verities: The Requirements For Successful Defense

A Sherman tank of the U.S. Army 9th Armored Division heads into action against the advancing Germans during the Battle of the Bulge. {Warfare History Network]

The eighth of Trevor Dupuy’s Timeless Verities of Combat is:

Successful defense requires depth and reserves.

From Understanding War (1987):

Successful defense requires depth and reserves. It has been asserted that outnumbered military forces cannot afford to withhold valuable firepower from ongoing defensive operations and keep it idle in reserve posture. History demonstrates that this is specious logic, and that linear defense is disastrously vulnerable. Napoleon’s crossing of the Po in his first campaign in 1796 is perhaps the classic demonstration of the fallacy of linear (or cordon) defense.

The defender may have all of his firepower committed to the anticipated operational area, but the attacker’s advantage in having the initiative can always render much of that defensive firepower useless. Anyone who suggests that modern technology will facilitate the shifting of engaged firepower in battle overlooks three considerations: (a) the attacker can inhibit or prevent such movement by both direct and indirect means, (b) a defender engaged in a fruitless firefight against limited attacks by numerically inferior attackers is neither physically nor psychologically attuned to making lateral movements even if the enemy does not prevent or inhibit it, and (c) withdrawal of forces from the line (even if possible) provides an alert attacker with an opportunity for shifting the thrust of his offensive to the newly created gap in the defenses.

Napoleon recognized that hard-fought combat is usually won by the side committing the last reserves. Marengo, Borodino, and Ligny are typical examples of Napoleonic victories that demonstrated the importance of having resources available to tip the scales. His two greatest defeats, Leipzig and Waterloo, were suffered because his enemies still had reserves after his were all committed. The importance of committing the last reserves was demonstrated with particular poignancy at Antietam in the American Civil War. In World War II there is no better example than that of Kursk. [pp. 5-6]

Dupuy’s observations about the need for depth and reserves for a successful defense take on even greater current salience in light of the probably character of the near-future battlefield. Terrain lost by an unsuccessful defense may be extremely difficult to regain under prevailing circumstances.

The interaction of increasing weapon lethality and the operational and human circumstantial variables of combat continue to drive the long-term trend in dispersion of combat forces in frontage and depth.

Long-range precision firepower, ubiquitous battlefield reconnaissance and surveillance, and the effectiveness of cyber and information operations will make massing of forces and operational maneuver risky affairs.

As during the Cold War, the stability of alliances may depend on a willingness to defend forward in the teeth of effective anti-access/area denial (A2/AD) regimes that will make the strategic and operational deployment of reserves risky as well. The successful suppression of A2/AD networks might court a nuclear response, however.

Finding an effective solution for enabling a successful defense-in-depth in the future will be a task of great difficulty.

Dupuy’s Verities: The Advantage Of The Offensive

Union assault on the “Mule Shoe” salient, 12 May 1864, by Thure de Thulstrup (1887) [Wikimedia]

The seventh of Trevor Dupuy’s Timeless Verities of Combat is:

An attacker willing to pay the price can always penetrate the strongest defenses.

From Understanding War (1987):

No matter how alert the defender, no matter how skillful his dispositions to avoid or mitigate the effects of surprise or the effects of flank or rear attack, a skillful attacker can always achieve at least a temporary advantage for some time at a place he has selected. This is one reason why Napoleon always endeavored to seize and retain the initiative. In the great battles of 1864 and 1865 in Virginia, Lee was always able to exploit his defensive advantage to the utmost. But Grant equally was always able to achieve a temporary superiority when and where he wished. This did not always result in a Union victory—given Lee’s defensive skill—but invariably it forced Lee to retreat until he could again impose a temporary stalemate with the assistance of powerful field fortifications. A modern example can be found in the Soviet offensive relieving Leningrad in 1943. Another was the Allied break-out from the Normandy beachhead in July and August of 1944.

The exact meaning of this verity is tricky to determine, as the phrase “willing to pay the price” does a lot of work here. History is certainly replete with examples of Phyrric victories, where the cost paid for battlefield success deprived the attacker of any clear benefit. (The U.S. Civil War Battle of Chickamauga in 1863 would be an example in line with Dupuy’s description above.) Perhaps “willing and able to pay the price” would have been a better of way stating this. And, of course, no attack is guaranteed to succeed.

What Dupuy had in mind here is probably best understood in the context of two other of his verities “Offensive action is essential to positive combat results” and “Initiative permits application of preponderant combat power.” Even if the defensive may be the stronger form of combat, the offensive affords certain inherent potential advantages that can enable attackers to defeat the strongest of defenses if conducted effectively, sufficiently resourced, and determinedly pressed.

Dupuy’s Verities: Fortification

The Maginot Line was a 900-mile long network of underground bunkers, tunnels and concrete retractable gun batteries. Its heaviest defenses were located along the 280-mile long border with Germany. [WikiCommons]

The sixth of Trevor Dupuy’s Timeless Verities of Combat is:

Defenders’ chances of success are directly proportional to fortification strength.

From Understanding War (1987):

To some modern military thinkers this is a truism needing no explanation or justification. Others have asserted that prepared defenses are attractive traps to be avoided at all costs. Such assertions, however, either ignore or misread historical examples. History is so fickle that it is dangerous for historians to use such words as “always” or “never.” Nevertheless I offer a bold counter-assertion: never in history has a defense been weakened by the availability of fortifications; defensive works always enhance combat strength. At the very least, fortifications will delay an attacker and add to his casualties; at best, fortifications will enable the defender to defeat the attacker.

Anyone who suggests that breakthroughs of defensive positions in recent history demonstrate the bankruptcy of defensive posture and/or fortifications is seriously deceiving himself and is misinterpreting modern history. One can cite as historical examples the overcoming of the Maginot Line, the Mannerheim Line, the Siegfried Line, and the Bar Lev Line, and from these examples conclude that these fortifications failed. Such a conclusion is absolutely wrong. It is true that all of these fortifications were overcome, but only because a powerful enemy was willing to make a massive and costly effort. (Of course, the Maginot Line was not attacked frontally in 1940; the Germans were so impressed by its defensive strength that they bypassed it, and were threatening its rear when France surrendered.) All of these fortifications afforded time for the defenders to make new dispositions, to bring up reserves, or to mobilize. All were intended to obstruct, to permit the defenders to punish the attackers and, above all to delay; all were successful in these respects. The Bar Lev Line, furthermore, saved Israel from disastrous defeat, and became the base for a successful offensive.[p. 4]

Will field fortifications continue to enhance the combat power of land forces on future battlefields? This is an interesting question. While the character of existing types of fortifications—trenches, strongpoint, and bunkers—might change, seeking cover and concealment from the earth might become even more important.

Dr. Alexander Kott, Chief Scientist at the U.S. Army Research Laboratory, provided one perspective in a recently published paper titled “Ground Warfare in 2050: How It Might Look.” In it, Kott speculated about “tactical ground warfighting circa 2050, in a major conflict between technologically advanced peer competitors.”

Kott noted that on future battlefields dominated by sensor saturation and long-range precision fires, “Conventional entrenchments and other fortifications will become less effective when teams of intelligent munitions can maneuver into and within a trench or a bunker.” Light dismounted forces “will have limited, if any, protection either from antimissiles or armor (although they may be provided a degree of protection by armor deployed by their robotic helpers… Instead, they will use cluttered ground terrain to obtain cover and concealment. In addition, they will attempt to distract and deceive…by use of decoys.”

Heavy forces “capable of producing strong lethal effects—substantial in size and mounted on vehicles—will be unlikely to avoid detection, observation, and fires.” To mitigate continuous incoming precision fires, Kott envisions that heavy ground forces will employ a combination of cover and concealment, maneuver, dispersion, decoys, vigorous counter-ISR (intelligence, surveillance, and reconnaissance) attacks, and armor, but will rely primarily “on extensive use of intelligent antimissiles (evolutions of today’s Active Protection Systems [APSs], Counter Rocket, Artillery, and Mortar [C-RAM], Iron Dome, etc.)”

Conversely, Kott does not foresee underground cover and concealment disappearing from future battlefields. “To gain protection from intelligent munitions, extended subterranean tunnels and facilities will become important. This in turn will necessitate the tunnel-digging robotic machines, suitably equipped for battlefield mobility.” Not only will “large static assets such as supply dumps or munitions repair and manufacturing shops” be moved underground, but maneuver forces and field headquarters might conceivably rapidly dig themselves into below-ground fighting positions between operational bounds.

Dupuy’s Verities: Initiative

German Army soldiers advance during the Third Battle of Kharkov in early 1943. This was the culmination of a counteroffensive by German Field Marshal Erich von Manstein that blunted the Soviet offensive drive following the recapture of Stalingrad in late 1942. [Photo: KonchitsyaLeto/Reddit]

The fifth of Trevor Dupuy’s Timeless Verities of Combat is:

Initiative permits application of preponderant combat power.

From Understanding War (1987):

The importance of seizing and maintaining the initiative has not declined in our times, nor will it in the future. This has been the secret of success of all of the great captains of history. It was as true of MacArthur as it was of Alexander the Great, Grant or Napoleon. Some modern Soviet theorists have suggested that this is even more important now in an era of high technology than formerly. They may be right. This has certainly been a major factor in the Israeli victories over the Arabs in all of their wars.

Given the prominent role initiative has played in warfare historically, it is curious that it is not a principle of war in its own right. However, it could be argued that it is sufficiently embedded in the principles of the offensive and maneuver that it does not need to be articulated separately. After all, the traditional means of sizing the initiative on the battlefield is through a combination of the offensive and maneuver.

Initiative is a fundamental aspect of current U.S. Army doctrine, as stated in ADP 3-0 Operations (2017):

The central idea of operations is that, as part of a joint force, Army forces seize, retain, and exploit the initiative to gain and maintain a position of relative advantage in sustained land operations to prevent conflict, shape the operational environment, and win our Nation’s wars as part of unified action.

For Dupuy, the specific connection between initiative and combat power is likely why he chose to include it as a verity in its own right. Combat power was the central concept in his theory of combat and initiative was not just the basic means of achieving a preponderance of combat power through superior force strength (i.e. numbers), but also in harnessing the effects of the circumstantial variables of combat that multiply combat power (i.e. surprise, mobility, vulnerability, combat effectiveness). It was precisely through the exploitation of this relationship between initiative and combat power that allowed inferior numbers of German and Israeli combat forces to succeed time and again in combat against superior numbers of Soviet and Arab opponents.

Using initiative to apply preponderant combat power in battle is the primary way the effects of maneuver (to “gain and maintain a position of relative advantage“) are abstracted in Dupuy’s Quantified Judgement Model (QJM)/Tactical Numerical Deterministic Model (TNDM). The QJM/TNDM itself is primarily a combat attrition adjudicator that determines combat outcomes through calculations of relative combat power. The numerical force strengths of the opposing forces engaged as determined by maneuver can be easily inputted into the QJM/TNDM and then modified by the applicable circumstantial variables of combat related to maneuver to obtain a calculation of relative combat power. As another of Dupuy’s verities states, “superior combat power always wins.”

Dupuy’s Verities: The Utility Of Defense

Battle of Franklin, 1864 by Kurz and Allison. Restoration by Adam Cuerden [Wikimedia Commons]

The third of Trevor Dupuy’s Timeless Verities of Combat is:

Defensive posture is necessary when successful offense is impossible.

From Understanding War (1987):

Even though offensive action is essential to ultimate combat success, a combat commander opposed by a more powerful enemy has no choice but to assume a defensive posture. Since defensive posture automatically increases the combat power of his force, the defending commander at least partially redresses the imbalance of forces. At a minimum he is able to slow down the advance of the attacking enemy, and he might even beat him. In this way, through negative combat results, the defender may ultimately hope to wear down the attacker to the extent that his initial relative weakness is transformed into relative superiority, thus offering the possibility of eventually assuming the offensive and achieving positive combat results. The Franklin and Nashville Campaign of our Civil War, and the El Alamein Campaign of World War II are examples.

Sometimes the commander of a numerically superior offensive force may reduce the strength of portions of his force in order to achieve decisive superiority for maximum impact on the enemy at some other critical point on the battlefield, with the result that those reduced-strength components are locally outnumbered. A contingent thus reduced in strength may therefore be required to assume a defensive posture, even though the overall operational posture of the marginally superior force is offensive, and the strengthened contingent of the same force is attacking with the advantage of superior combat power. A classic example was the role of Davout at Auerstadt when Napoléon was crushing the Prussians at Jena. Another is the role played by “Stonewall” Jackson’s corps at the Second Battle of Bull Run. [pp. 2-3]

This verity is both derivative of Dupuy’s belief that the defensive posture is a human reaction to the lethal environment of combat, and his concurrence with Clausewitz’s dictum that the defense is the stronger form of combat. Soldiers in combat will sometimes reach a collective conclusion that they can no longer advance in the face of lethal opposition, and will stop and seek cover and concealment to leverage the power of the defense. Exploiting the multiplying effect of the defensive is also a way for a force with weaker combat power to successfully engage a stronger one.

It also relates to the principle of war known as economy of force, as defined in the 1954 edition of the U.S. Army’s Field Manual FM 100-5, Field Service Regulations, Operations:

Minimum essential means must be employed at points other than that of decision. To devote means to unnecessary secondary efforts or to employ excessive means on required secondary efforts is to violate the principle of both mass and the objective. Limited attacks, the defensive, deception, or even retrograde action are used in noncritical areas to achieve mass in the critical area.

These concepts are well ingrained in modern U.S. Army doctrine. FM 3-0 Operations (2017) summarizes the defensive this way:

Defensive tasks are conducted to defeat an enemy attack, gain time, economize forces, and develop conditions favorable for offensive or stability tasks. Normally, the defense alone cannot achieve a decisive victory. However, it can set conditions for a counteroffensive or counterattack that enables Army forces to regain and exploit the initiative. Defensive tasks are a counter to enemy offensive actions. They defeat attacks, destroying as much of an attacking enemy as possible. They also preserve and maintain control over land, resources, and populations. The purpose of defensive tasks is to retain key terrain, guard populations, protect lines of communications, and protect critical capabilities against enemy attacks and counterattacks. Commanders can conduct defensive tasks to gain time and economize forces, so offensive tasks can be executed elsewhere. [Para 1-72]

UPDATE: Just as I posted this, out comes a contrarian view from U.S. Army CAPT Brandon Morgan via the Modern War Institute at West Point blog. He argues that the U.S. Army is not placing enough emphasis on preparing to conduct defensive operations:

In his seminal work On War, Carl von Clausewitz famously declared that, in comparison to the offense, “the defensive form of warfare is intrinsically stronger than the offensive.”

This is largely due to the defender’s ability to occupy key terrain before the attack, and is most true when there is sufficient time to prepare the defense. And yet within the doctrinal hierarchy of the four elements of decisive action (offense, defense, stability, and defense support of civil authorities), the US Army prioritizes offensive operations. Ultimately, this has led to training that focuses almost exclusively on offensive operations at the cost of deliberate planning for the defense. But in the context of a combined arms fight against a near-peer adversary, US Army forces will almost assuredly find themselves initially fighting in a defense. Our current neglect of deliberate planning for the defense puts these soldiers who will fight in that defense at grave risk.

The Combat Value of Surprise

American soldiers being marched down a road after capture by German troops in the Ardennes, December 1944.
American soldiers being marched down a road after capture by German troops in the Ardennes, December 1944.

[This article was originally posted on 1 December 2016]

In his recent analysis of the role of conventional armored forces in Russian hybrid warfare, U.S. Army Major Amos Fox noted an emphasis on tactical surprise.

Changes to Russian tactics typify the manner in which Russia now employs its ground force. Borrowing from the pages of military theorist Carl von Clausewitz, who stated, “It is still more important to remember that almost the only advantage of the attack rests on its initial surprise,” Russia’s contemporary operations embody the characteristic of surprise. Russian operations in Georgia and Ukraine demonstrate a rapid, decentralized attack seeking to temporally dislocate the enemy, triggering the opposing forces’ defeat.

Tactical surprise enabled by electronic, cyber, information and unconventional warfare capabilities, combined with mobile and powerful combined arms brigade tactical groups, and massive and lethal long-range fires provide Russian Army ground forces with formidable combat power.

Trevor Dupuy considered the combat value of surprise to be important enough to cite it as one of his “timeless verities of combat.”

Surprise substantially enhances combat power. Achieving surprise in combat has always been important. It is perhaps more important today than ever. Quantitative analysis of historical combat shows that surprise has increased the combat power of military forces in those engagements in which it was achieved. Surprise has proven to be the greatest of all combat multipliers. It may be the most important of the Principles of War; it is at least as important as Mass and Maneuver.

In addition to acting as combat power multiplier, Dupuy observed that surprise decreases the casualties of a surprising force and increases those of a surprised one. Surprise also enhances advance rates for forces that achieve it.

In his combat models, Dupuy categorized tactical surprise as complete, substantial, and minor; defining the level achieved was a matter of analyst judgement. The combat effects of surprise in battle would last for three days, declining by one-third each day.

He developed two methods for applying the effects of surprise in calculating combat power, each yielding the same general overall influence. In his original Quantified Judgement Model (QJM) detailed in Numbers, Predictions and War: The Use of History to Evaluate and Predict the Outcome of Armed Conflict (1977), factors for surprise were applied to calculations for vulnerability and mobility, which in turn were applied to the calculation of overall combat power. The net value of surprise on combat power ranged from a factor of about 2.24 for complete surprise to 1.10 for minor surprise.

For a simplified version of his combat power calculation detailed in Attrition: Forecasting Battle Casualties and Equipment Losses in Modern War (1990), Dupuy applied a surprise combat multiplier value directly to the calculation of combat power. These figures also ranged between 2.20 for complete surprise and 1.10 for minor surprise.

Dupuy established these values for surprise based on his judgement of the difference between the calculated outcome of combat engagements in his data and theoretical outcomes based on his models. He never validated them back to his data himself. However, TDI President Chris Lawrence recently did conduct substantial tests on TDI’s expanded combat databases in the context of analyzing the combat value of situational awareness. The results are described in detail in his forthcoming book, War By Numbers: Understanding Conventional Combat.

Dupuy’s Verities: The Power Of Defense

Leonidas at Thermopylae, by Jacques-Louis David, 1814. [Wikimedia]

The second of Trevor Dupuy’s Timeless Verities of Combat is:

Defensive strength is greater than offensive strength.

From Understanding War (1987):

[Prussian military theorist, Carl von] Clausewitz expressed this: “Defense is the stronger form of combat.” It is possible to demonstrate by the qualitative comparison of many battles that Clausewitz is right and that posture has a multiplicative effect on the combat power of a military force that takes advantage of terrain and fortifications, whether hasty and rudimentary, or intricate and carefully prepared. There are many well-known examples of the need of an attacker for a preponderance of strength in order to carry the day against a well-placed and fortified defender. One has only to recall Thermopylae, the Alamo, Fredericksburg, Petersburg, and El Alamein to realize the advantage enjoyed by a defender with smaller forces, well placed, and well protected. [p. 2]

The advantages of fighting on the defensive and the benefits of cover and concealment in certain types of terrain have long been basic tenets in military thinking. Dupuy, however, considered defensive combat posture and defensive value of terrain not just to be additive, but combat power multipliers, or circumstantial variables of combat that when skillfully applied and exploited, the effects of which could increase the overall fighting capability of a military force.

The statement [that the defensive is the stronger form of combat] implies a comparison of relative strength. It is essentially scalar and thus ultimately quantitative. Clausewitz did not attempt to define the scale of his comparison. However, by following his conceptual approach it is possible to establish quantities for this comparison. Depending upon the extent to which the defender has had the time and capability to prepare for defensive combat, and depending also upon such considerations as the nature of the terrain which he is able to utilize for defense, my research tells me that the comparative strength of defense to offense can range from a factor with a minimum value of about 1.3 to maximum value of more than 3.0. [p. 26]

The values Dupuy established for posture and terrain based on historical combat experience were as follows:

For example, Dupuy calculated that mounting even a hasty defense in rolling, gentle terrain with some vegetation could increase a force’s combat power by more than 50%. This is a powerful effect, achievable without the addition of any extra combat capability.

It should be noted that these values are both descriptive, in terms of defining Dupuy’s theoretical conception of the circumstantial variables of combat, as well as factors specifically calculated for use in his combat models. Some of these factors have found their way into models and simulations produced by others and some U.S. military doctrinal publications, usually without attribution and shorn of explanatory context. (A good exploration of the relationship between the values Dupuy established for the circumstantial variables of combat and his combat models, and the pitfalls of applying them out of context can be found here.)

While the impact of terrain on combat is certainly an integral part of current U.S. Army thinking at all levels, and is constantly factored into combat planning and assessment, its doctrine does not explicitly acknowledge the classic Clausewitzian notion of a power disparity between the offense and defense. Nor are the effects of posture or terrain thought of as combat multipliers.

However, the Army does implicitly recognize the advantage of the defensive through its stubbornly persistent adherence to the so-called 3-1 rule of combat. Its version of this (which the U.S. Marine Corps also uses) is described in doctrinal publications as “historical minimum planning ratios,” which proscribe that a 3-1 advantage in numerical force ratio is necessary for an attacker to defeat a defender in a prepared or fortified position. Overcoming a defender in a hasty defense posture requires a 2.5-1 force ratio advantage. The force ratio advantages the Army considers necessary for decisive operations are even higher. While the 3-1 rule is a deeply problematic construct, the fact that is the only quantitative planning factor included in current doctrine reveals a healthy respect for the inherent power of the defensive.

Dupuy’s Verities: Offensive Action

Sheridan’s final charge at Winchester by Thune de Thulstrup (ca. 1886) [Library of Congress]

The first of Trevor Dupuy’s Timeless Verities of Combat is:

Offensive action is essential to positive combat results.

As he explained in Understanding War (1987):

This is like saying, “A team can’t score in football unless it has the ball.” Although subsequent verities stress the strength, value, and importance of defense, this should not obscure the essentiality of offensive action to ultimate combat success. Even in instances where a defensive strategy might conceivably assure a favorable war outcome—as was the case of the British against Napoleon, and as the Confederacy attempted in the American Civil War—selective employment of offensive tactics and operations is required if the strategic defender is to have any chance of final victory. [pp. 1-2]

The offensive has long been a staple element of the principles of war. From the 1954 edition of the U.S. Army Field Manual FM 100-5, Field Service Regulations, Operations:

71. Offensive

Only offensive action achieves decisive results. Offensive action permits the commander to exploit the initiative and impose his will on the enemy. The defensive may be forced on the commander, but it should be deliberately adopted only as a temporary expedient while awaiting an opportunity for offensive action or for the purpose of economizing forces on a front where a decision is not sought. Even on the defensive the commander seeks every opportunity to seize the initiative and achieve decisive results by offensive action. [Original emphasis]

Interestingly enough, the offensive no longer retains its primary place in current Army doctrinal thought. The Army consigned its list of the principles of war to an appendix in the 2008 edition of FM 3-0 Operations and omitted them entirely from the 2017 revision. As the current edition of FM 3-0 Operations lays it out, the offensive is now placed on the same par as the defensive and stability operations:

Unified land operations are simultaneous offensive, defensive, and stability or defense support of civil authorities’ tasks to seize, retain, and exploit the initiative to shape the operational environment, prevent conflict, consolidate gains, and win our Nation’s wars as part of unified action (ADRP 3-0)…

At the heart of the Army’s operational concept is decisive action. Decisive action is the continuous, simultaneous combinations of offensive, defensive, and stability or defense support of civil authorities tasks (ADRP 3-0). During large-scale combat operations, commanders describe the combinations of offensive, defensive, and stability tasks in the concept of operations. As a single, unifying idea, decisive action provides direction for an entire operation. [p. I-16; original emphasis]

It is perhaps too easy to read too much into this change in emphasis. On the very next page, FM 3-0 describes offensive “tasks” thusly:

Offensive tasks are conducted to defeat and destroy enemy forces and seize terrain, resources, and population centers. Offensive tasks impose the commander’s will on the enemy. The offense is the most direct and sure means of seizing and exploiting the initiative to gain physical and cognitive advantages over an enemy. In the offense, the decisive operation is a sudden, shattering action that capitalizes on speed, surprise, and shock effect to achieve the operation’s purpose. If that operation does not destroy or defeat the enemy, operations continue until enemy forces disintegrate or retreat so they no longer pose a threat. Executing offensive tasks compels an enemy to react, creating or revealing additional weaknesses that an attacking force can exploit. [p. I-17]

The change in emphasis likely reflects recent U.S. military experience where decisive action has not yielded much in the way of decisive outcomes, as is mentioned in FM 3-0’s introduction. Joint force offensives in 2001 and 2003 “achieved rapid initial military success but no enduring political outcome, resulting in protracted counterinsurgency campaigns.” The Army now anticipates a future operating environment where joint forces can expect to “work together and with unified action partners to successfully prosecute operations short of conflict, prevail in large-scale combat operations, and consolidate gains to win enduring strategic outcomes” that are not necessarily predicated on offensive action alone. We may have to wait for the next edition of FM 3-0 to see if the Army has drawn valid conclusions from the recent past or not.