Return to Gettysburg: The Fifth Epochal Shift in the Course of War


It’s a spot of ground at Gettysburg the Park Service guides rarely frequent. Over a thousand monuments dot the battlefield, but none are here. Yet for those who view the past as prologue this patch of grass just south of the Lutheran Seminary holds a prescient place in history. It was exactly here late on the first day of battle in 1863 that Robert E. Lee and James Longstreet held their Socratic dialogue that would change the course of American history. And over the next half century this dialogue would serve as a seminal marker in the evolution of the art of war.

Just a month before Gettysburg, Lee demonstrated his operational genius dramatically at Chancellorsville. It was a most improbable victory. Military historians regard it as Lee’s Austerlitz, comparing Lee’s genius to Napoleon’s greatest moment in battle. Outnumbered five to three, Lee violated two of the most sacred tenets of war by dividing his force into thirds in the face of the enemy and attacking when all odds were against him.

Longstreet’s corps wasn’t at Chancellorsville. It was Thomas “Stonewall” Jackson’s troops that conducted the magnificent end-run around “Fighting Joe” Hooker’s Eleventh Corps that brutally smashed the Union forces and determined the course of the battle. After Chancellorsville, Longstreet had a moment to view Lee’s great victory dispassionately. He saw the battle not as a victory so much as a bloody sacrifice nearly as costly in Confederate dead as that suffered by the defeated.

Longstreet had already had the dialogue with Lee during the long, cold winter months of 1862 and 1863. He was by no means a futurist, but Longstreet understood intuitively the technology that had made this war fundamentally different from those of the past. The muzzle-loading rifle was killing soldiers on both sides at ranges impossible during the Mexican-American War. Rifling extended the lethal range of the defensive by a factor of five or more from the smooth bore guns used by Winfield Scott’s regulars at Chapultepec.

Longstreet suggested to Lee that the South could no longer afford bloody victories that relied on the offensive like Chancellorsville. Perhaps a better solution might be to maneuver wide enough to turn the enemy out of his defenses and force him to attack over ground defended by Confederate infantry. Lee disagreed and paid a horrific price for his shortsightedness. In years to come, European Armies would follow Lee’s impulses, not Longstreet’s wisdom, and would pay a butcher’s bill that would leave seven million dead on the blood-soaked fields of Flanders and Verdun.

Gettysburg is with us again and with it Longstreet’s ghost is repeating its deadly lament. I’m writing not to condemn Lee and those European generals to follow, but to excuse them. Even Longstreet was clueless when it came to the long-term consequences of events he witnessed. Some might excuse them because the Gods of War are a perfidious and devious lot who know how to hide the consequences inherent in the evolution of deadly quarrels, until the bill for folly is fully paid.


Here’s what we know: The Civil War marked the end of the third cycle in the evolution of ground warfare. Advances in the tools of war promulgated each shift. The first cycle, the great age of infantry, began in the clouded era of Neolithic man and lasted for three thousand years. Battles then were muscle-powered affairs decided by the offensive swing of sword or push of pike and lance. The phalanx and the legion marked the high points of this epoch.

The second cycle that signaled a shift away from infantry was marked symbolically by the Battle of Adrianople fought in Macedonia in 378 AD. Hordes of mounted Huns defeated Rome’s legions and ended infantry’s dominance in battle for five hundred years. As with all cyclic shifts, this first “mounted era” in warfare was enabled by technology that began with the weaponization of the horse: the Arabian horse of Islamic armies, the steppe pony of the Mongols, and the heavy dray horse of Western knights. The mobility of the horse was amplified by the invention of the stirrup, which gave mounted horseman leverage to wield lance and arrow. The introduction of the composite bow allowed the mounted warrior to kill at a distance.

The horse gave ground forces the strategic mobility to conduct offensive maneuvers globally: Mounted Mongols under Genghis Khan and Tamerlane conquered most of the world island from China to the gates of Vienna; Saracens conquered the Middle East and North Africa to the foothills of the Pyrenees; mounted European knights recaptured the Holy Land during the crusades of the late Middle Ages.

The third cyclic shift returned battlefield dominance to infantry, and again it was technology, specifically gunpowder weapons, that allowed illiterate Spanish infantrymen to strike down the cream of the French nobility at the battle of Pavia in 1525. Harquebus-toting Spanish, English, and French infantry transported by square-sailed vessels colonized most of the known world before the first signs of the demise of infantry appeared at Gettysburg.

The end of the third cycle and the shift away from the dominance of infantry, as first witnessed at Gettysburg, had profound consequences. As Longstreet suspected, technology had swung the pendulum separating maneuver and firepower toward the latter. A perennial tenet of warfare dictates that firepower dominance always favors the defensive. Firepower dominance is achieved by the multiplicative factors of range, lethality, and precision. All three underwent profound advances as a consequence of the industrial revolution.

Smokeless powder was the principal catalyst for introducing this “first precision revolution” as it came to be known. Beginning in the 1880s, small caliber firearms could now fire 15 rounds per minute out to ranges well beyond a mile. Repeating arms gave way to automatic arms in the form of the Maxim machine gun. At the turn of the 20th century, longer ranging, quick firing artillery capable of delivering explosive shells precisely out to ranges of ten miles or more came into service in European armies.

Other fruits of the industrial revolution increased the slaughter of battle between industrial powers. The railroad delivered soldiers, weapons, and ammunition to the battlefield in industrial strength and made warfare a yearlong affair. The telegraph and later the wireless gave generals the means to mass armies by the millions. Mines and barbed wire increased the cost of crossing the “deadly zone” by an order of magnitude. Inventive genius elevated the airplane from a curiosity to a killing machine. In a strange twist of irony the discovery of the germ theory of disease in the 1880s saved soldiers from death by microbes so they could be slaughtered in greater numbers by bullets and shrapnel.

The third cycle ended in the trenches of the Western Front. By the time of the Great War the three deadly components of a firepower-intensive battle — lethality, range, and precision — multiplied together to make the crossing of the deadly zone between opposing forces virtually impossible. The killing range of rifles and machine guns increased the zone from 50 yards in Napoleon’s time to a mile or more in some World War I battles. By 1914, artillery had become precision instruments for killing with indirect fire. With precision came lethality that saturated the deadly zone with so much lead and steel that even the most determined attack failed. While the deadly zone increased ten-fold, the speed of the offensive was limited to a walk, as it was in Caesar’s time.

The wisdom of hindsight revealed by the horrors of the Western Front still confounds us a century on. How did so many professionals fail to foresee the consequences of a dying third cycle before the Great War? Why didn’t armies strive to find a solution to crossing the deadly zone before so many soldiers died? The reasons for this deadly ignorance are, as always, embedded in the human intellect. And they form a cautionary tale for today’s military elites. Much that happened then is repeating today.

To be fair, prior to World War I, Western militaries received ambiguous signals. The lessons of the American Civil War seemed mildly instructive to European armies at the time, but were soon eclipsed by first-hand experience in the Franco-Prussian War. The rapid collapse of Napoleon III’s Army at Sedan in 1870 sent the false signal that technology favored the offensive and offered the promise that wars of the future would be short, glorious, bloodless, and profitable. Colonial wars also sent erroneous signals. Again these conflicts pitted machine weapons against less technologically advanced peoples and promised that technology would overcome both mass and fanaticism.

Time also played a part. By 1914, Europe had been spared cataclysmic war for exactly a century. With the passing of peaceful decades, military men tended to favor the memories of contemporary wars fought in distant lands to the theorizing of culturally disconnected elites. As we see today, in the end the views of the practical soldier always prevails. To borrow from Napoleon: The visceral trumps the vicarious as three is to one.

And to give soldiers their due, military thinkers of the period did try to anticipate the consequences of technology to some degree. These were not stupid men. Longstreet’s successors were luminaries like Ardant Du Picq, Ferdinand Foch, Sir John Caldwell, Friedrich von Bernhardi, among many others. Military journals from the gilded age were rich with insightful debate. A few even got it right. The obscure Swiss banker Jean de Bloch’s prescient volume The Future of War, written in 1898, anticipated with great fidelity the bloody consequences of the Great War. Bloch wasn’t ignored entirely. But professional soldiers remained convinced that the human spirit and “Élan” would triumph over the accelerating pace of killing technologies.

The fourth (and some would argue the last) cycle in the conduct of war was again precipitated by technology and accelerated by the imperative never to repeat the horrors of the Great War. During the interwar years, all modern militaries rightfully concluded that wireless and internal combustion engine would be the keys to returning dominance to the offensive. Even though World War II would be costlier than its predecessor, the application of these two technologies in the form of armored vehicles and aircraft would prevent prolonged stalemate and facilitate maneuver. At war’s end, it was evident that that machine age had arrived and the United States, with its extraordinarily robust industrial and technological dominance, would be best positioned to exploit the advantage.

The period from Hiroshima to the present would henceforth be commonly accepted as the “American Era of War.” We were sole inheritors of the fourth cycle. End of story. We won. Or did we? What if the ground under us is shifting again for a fifth time? Are we too smug (or too close to events) to see it? To gain some perspective, let’s return for a moment to Gettysburg.

Comparing today with the mid-19th century is compelling. And as with all previous cyclic shifts the motive force propelling the beginnings of a fifth cycle is technology. Since I was commissioned in 1966 we have seen the arrival of a “Second Precision Revolution.” Consider again the primal elements of a firepower-dominated battlefield in modern context.

In terms of precision, the probable error for weapons has gone from hundreds of meters for ground delivered fires and kilometers for aerial weapons to less than a meter in most cases. In World War II, the average tank on tank engagement required 17 rounds. Today it’s one round, one kill.

When it comes to lethality, the killing power of conventional weapons has increased in proportion to the ability of weapons to hit close and inflict greater casualties over much larger areas. As we learned in Iraq and Afghanistan, advances in sensor technology concentrate lethality by making the battlefield more transparent. To be sure, adaptive enemies will always find ways to avoid detection. But the battlefield is becoming transparent enough for big, expensive systems to be easily targeted. Aerial and space-based sensors are increasingly able to find armored vehicles, artillery, logistic nodes, and large communications complexes. And more to the point: The more systems mass, the more likely they are to be seen and killed.

The area of range has seen perhaps the most impactful technological amplifications. The reach of aerial- and ground-delivered killing power has grown an order of magnitude since the Cold War and promises greater increases in the years ahead. Conventional artillery will reach beyond 100 kilometers soon, rocket artillery perhaps as far as 1,000 kilometers. The ability to see and sense, particularly with aerial and space-based sensors, will match or exceed the range of firepower systems.

If the past is prologue and if a firepower-dominant battlefield favors the defensive, we are witnessing a figurative “return to Gettysburg.” This fifth cycle now underway will likely make the offensive costlier and more difficult. But the Gods of War again are clouding our vision. The evidence for a fifth shift is ambiguous and conflicting, just as it was in 1914. Some would argue it’s simply too soon for another cycle. This would be a good argument if the intervals of change were constant. But a shift that took a millennium in the agricultural age took only a century in the machine age and perhaps will take only a generation today.

But remember my caution about the visceral trumping the vicarious — practical soldiers point to recent wars: the Arab-Israeli wars, the Great Wheel of Desert Storm, and the March to Baghdad in 2003, to argue that the fourth cycle has yet to fully mature. The challenge of this argument is the same today as it was in the 19th century: It’s been three quarters of a century since we’ve witnessed a peer-on-peer conflict fought on first world terrain such as Western Europe and northeast Asia. The few mechanized wars we’ve witnessed since the end of World War II have been painfully asymmetric with former colonial supplicants trying to fight Western armies the Western way. When these same armies fight their way they become far more successful in confronting and defeating Western “fourth cycle” armies.

America’s enemies have adapted well to our dominance in technology and materiel. In Korea, Vietnam, Iraq, and now in Afghanistan non-Western militaries (much like those who opposed colonial powers during the third cycle) are taking advantage of the inherent power of the defensive. To lessen our dominance in range, lethality, and precision they disperse, dig in, and fight among the people. They have been able to leverage our liberal sympathies by capturing the global media to highlight every battlefield transgression. They counter America’s monopoly on killing power with their ownership of time, patience, and willingness to die. They counter America’s cutting-edge technology with the creative use of proven technologies like mortars, cell phones, shoulder fired missiles, small arms, RPGs, and IEDs. The battlefield stasis America’s enemies have cobbled together since the end of World War II suggests that an ounce of third cycle defensive might be worth a pound of fourth cycle offensive.

Let’s return to Gettysburg once more: This time imagine how the cyclic shift to the defensive presaged by the appearance of the rifled musket at Gettysburg might translate to a different battle, yet to be fought between matched global powers facing off on a piece of first world terrain. Let’s anticipate events to come by suggesting ways to preempt the coming slaughter. I foresee three options for swinging the pendulum from the defensive back to the offensive and perhaps in the process creating another cyclic shift within a single generation.

Firepower Escalation

The first alternative is the brute force solution: to develop an overwhelming firepower advantage in terms of lethality, range, and precision, such that the enemy is unable to resist our coalition’s offensive. In a way, this solution would be a replay of AirLand Battle doctrine of the 1980s. A massive “strike complex” consisting of air- and land-based components would conduct fire strikes deep into the enemy’s rear and spread across all of his echeloned bands of defenses beginning at the point of contact and continuing well beyond the deadly zone to depths of 100 kilometers or more.

The brute force solution is seductive because it plays to American preferences. The American military has always favored the firepower intensive battle. It is most likely to own the air and it has decades of experience on how best to exploit this advantage. The U.S. military will be able to amplify the lethality of its firepower systems by dominating the electromagnetic spectrum. Its superior offensive electronic and cyber capabilities should be able to deceive and “blind” the enemy while tracking and killing him at great depths.

But the drawbacks of a firepower approach as a means of restoring the offensive are many. The fact that brute force worked so well in Desert Storm shouldn’t blind Washington to the fact that what worked then may not work so well in the future. For one thing, America’s probable enemies are nearly as accomplished as we are in the firepower battle. A battle fought on first world terrain favors the defensive. Enemies imbedded in mountains, wooded regions, and dense and scattered urban areas are very difficult to target and destroy with even the most sophisticated weapons and sensors.

From a historical perspective armies often overstate the suppressive effects of firepower. Three million rounds on the Somme promised to cut the wire and bury the Germans. It did neither and 28,000 soldiers were killed or wounded on the first day of battle. I can recall firing thousands of artillery rounds onto Hamburger Hill and directing hundreds of air strikes only to see the North Vietnamese appear out of clouds of smoke to kill our infantry in frightful aggregations. No, I think such a machine age solution smacks too much of attrition warfare and has passed its time.


A more compelling and contemporary approach is to take a page from the playbook of our Iraqi and Afghan enemies and fight a disaggregated battle. European terrain lends itself to dispersion. Better-trained and -led forces like ours tend to remain more cohesive and capable even when holding ground in very discrete, isolated units as small as companies and perhaps platoons. Over the past few decades the Marines have experimented successfully with such formations and have found that disaggregation makes the enemy’s targeting problem very difficult.

The challenge of disaggregated forces is to maintain the ability to mass fires and maneuver from dispersed positions. It can be done. Late in World War II, the Wehrmacht perfected the ability to assemble attack formations on very short notice from scattered clusters of small units. Disaggregation is made more feasible thanks to the micro-electronic revolution. Huge and vulnerable Cold War communications nodes can now be replaced with small discrete facilities, easy to hide and relatively invulnerable to detection. Thanks to the network, yesterday’s air defense and surface artillery complexes are much smaller and capable of operating as discrete (in some cases individually emplaced) weapons. Dispersed formations can only be kept cohesive and capable of massing on demand if a robust cyber network ties them together. Dominate the cyber spectrum and maneuver at will. Lose it and suffer the consequences of defeat in detail.

Aerial Maneuver

Here we apply the “Longstreet Solution”: Restore the offensive by finding the means to maneuver around, over, or through an enemy’s defenses. To envelop Meade on the second day at Gettysburg Longstreet would have had to swing his corps about twenty kilometers south of the Union left. A coalition corps of tomorrow would likely have to amplify that distance at least ten or twenty-fold. Assuming that our enemies have succeeded in adopting and proliferating their own precision systems, a ground maneuver force might have to endure hostile precision fires throughout the entire course of its movement.

The inter-war solution for accelerating the speed of operational maneuver was to exploit the internal combustion engine and wireless. What are tomorrow’s corollaries to these technologies? I’ve explored some of these in other writings. I am certain that traditional ground maneuver won’t suffice. Even the most advanced ground vehicles cannot overcome the tyranny of terrain. The speed of the fastest tank at a blown bridge is exactly zero.

Aerial maneuver might offer a solution. Consider an operational maneuver using a “hybrid” scheme wherein early entry forces, the tip of the maneuver spear, assault across the deadly zone by air to conduct an operational coup de main. The enveloping force would possess sufficient combat power and mass to defend an airhead once seized until ground maneuver elements link up to complete the envelopment.

The U.S. Army considered such a scheme in the 1990s using Air Force C-130 transports as operational maneuver vehicles to transport brigade sized units deep behind enemy lines. Before 9/11, the Army and Marine Corps explored the development of heavy lift rotorcraft capable of carrying light armored assault vehicles to distances approaching 1,000 kilometers.  Unfortunately, technology of the period was too immature to allow the development of rotorcraft capable of aerial envelopment over operational rather than tactical distances.

But many problems make the aerial solution difficult, at least in the context of contemporary times. As we experienced in Vietnam, aircraft are vulnerable and subject to catastrophic casualties when shot down. For another, the speed of an aerially delivered force is the same as the legion once it hits the ground. Ground forces delivered by air have limited endurance. Even though today’s lighter precision weapons and vehicles offer greater killing power and tactical mobility for less weight, there is a limit to how long a light force delivered to operational distances through the air can remain effective without relief. Finally, there’s the expense. Even a country as rich as ours would be hard-pressed to afford enough airlift to sustain a theater level or even a limited corps level operational maneuver.

Many who have read my past writings argue that in advocating for aerial envelopment I’m suggesting the “tank is dead.” Nothing is farther from the truth. Throughout every cyclic shift remnants of systems from previous epochs remained intact and useful: Horsemen were auxiliaries to the legion, infantry accompanied mounted formations throughout the early modern era, cavalry showed themselves (albeit briefly and tragically) on the Somme in 1914 and, today, even with our current fixation on restoring the offensive, light infantry comprise almost three quarters of Western close combat formations.

The Consequences of a Fifth Cyclic Shift

Whatever the ultimate approach, it’s important to fully recognize and factor in the challenges that a fifth cyclic shift will impose on our approach to ground warfare. For one, after 17 years of counter-insurgency warfare, the ground services are returning to classic tenets of the offensive. Multi-domain doctrine appears so far to be a revision of AirLand battle in which additional layers of cyber, information and electronic warfare are added to traditional combined, all-arms forces. How difficult will it be to create a corollary to multi-domain doctrine that presumes an inability to take the offensive in the face of overwhelming firepower?

Consider a few prudent ways to prepare for a battle biased toward the defensive. First, having forces fixed in place before conflict reduces vulnerability to enemy long-range fires. Dispersing these forces by scattering vulnerable nodes and arraying close combat formations across wide expanses lessens vulnerability to the fire strikes that will characterize the opening phase of a defensively oriented campaign. Protect the network at all costs. It’s entirely possible that networks will be the vulnerable centers of gravity in such campaigns. Dispersed formations are more dependent on cyber connections to remain cohesive when dispersed across vast distances. Fire strike complexes cannot dominate in the opening phases of a counter fire campaign if denied the network’s ability to connect sensors to shooters.

To protect from enemy long-range offensive fire strikes it would be prudent for ground forces to re-learn the art of camouflage, tactical dispersion, materiel hardening, and electronic deception. The Army is seventy years away from suffering aerial attack. A first priority must be to create a protective air defense bubble impervious to air attack. If possible we must develop a maneuver version of the Israeli “Iron Dome” area defense system to protect our installations from artillery and tactical missile strikes. Urban terrain will provide ideal protected zones for harboring large installations such as logistical nodes, command and control facilities, and assembly areas for major mechanized units. Therefore we should not only learn how to fight in cities but also how to hunker down and defend there.

Recognition of the fifth cyclic shift carries with it several cautions. First, contemporary western militaries are structured and biased toward the offensive. Gaining and holding ground are embedded in our DNA. As in 1914, a great deal of pain must be suffered before these primal proclivities are erased and replaced by a recognition of the killing powers of precision, lethality, and range. By no means am I suggesting that future armies should be constituted only for the defensive. But a healthy respect for the killing power inherent in the defensive is essential if we are to innovate the proper means for restoring the offensive.

In 1985, British author Richard Simpkin in his transformative book, Race to the Swift, offered a conceptual alternative to AirLand Battle. He subtitled the work “Thoughts on Twenty First Century Warfare” as if to subliminally testify to the fact that aerial maneuver as he postulated was a concept far beyond the means of any NATO nation at the time. Perhaps it’s time to resurrect Simpkin. Is it possible some time in the future to quite literally “fly over” a firepower-dominated battlefield? Mechanization accelerated the pace of the offensive from two and a half to 20 miles per hour and eliminated the firepower-induced stalemates of the Western Front. Can we now accelerate from 20 miles per hour to 200 miles per hour and vault over the looming tyranny of the defensive? I don’t know. But any progressive military institution should investigate.

Historians credit Lee with being our greatest operational genius. So if Lee failed to anticipate the cyclic shift evolving about him, how can we be assured that contemporary military leaders will do any better? Perhaps military schools might provide the institutional wisdom to replace Lee’s individual genius as we transit through these tempestuous times. One advantage denied Lee was the ability to anticipate the future using wargames. The ground services should begin now to faithfully inject the dynamics of range, lethality, and precision into existing war plans. A caution is important here. Too often gamers understate the impact of firepower in order to add dynamism to exercises. We cannot allow commanders to attempt unrealistic maneuvers without realistic exposure to the power of the defensive. To do otherwise would only imbed habits that might in some future conflict get soldiers needlessly killed.


Bob Scales is a retired major general and former commandant of the Army War College. He currently serves as senior advisor to Secretary Mattis’ Close Combat Lethality Task Force.

Image: Dale Gallon’s “Tomorrow We Must Attack