Simulating War: Three Enduring Lessons from the Louisiana Maneuvers

LM Jenny McArdle (1)

This article is the third and final in a series on digital defense. The first article looked at how the United States should bring tech experts and the innovative ideas they develop into the Department of Defense at an accelerated rate, and why those innovations should be shared with allies. The second essay explored how safety science and civilian AI can inform the use of AI in the military.



My God, Senator, that’s the reason I do it. I want the mistakes [made] down in Louisiana, not over in Europe, and the only way to do this thing is to try it out, and if it doesn’t work, find out what we need to make it work.

– Gen. George C. Marshall, 1941


On Monday, Sept. 15, 1941, a special kind of war was declared. As a tropical storm sent torrential rains throughout the Gulf of Mexico, swelling rivers and caking the ground in mud, 472,000 troops bivouacked between Shreveport and Lake Charles, Louisiana, for the largest (simulated) force-on-force battle in U.S. history. The opposing “red” force’s mission: invade “blue” territory and destroy the enemy concentrated near Lake Charles. Over the course of five days, a small, mobile red force and a numerically superior blue force maneuvered over 3,400 square miles, engaging in a series of tank and antitank skirmishes from the Red River to the Leesville-Many highway. At 15:30 on Friday, just as the red force’s eastern flank at Natchitoches started to crumble, the exercise was halted. Blue had seemingly prevailed.

Sept. 15 was the start of the Louisiana Maneuvers, a series of four exercises that took place over two separate venues — the Louisiana-Texas border and the Carolinas — with each spanning vast, scarcely populated areas of dense forests, uncharted swamps, and river crossings. The maneuvers can be heralded as a logistical achievement: At no other time has there been such a concentration of man and materiel on U.S. soil. However, their true worth was as a “combat college for troop leading” and as a field laboratory to test and train for emerging operational concepts. Indeed, notwithstanding some adjudicatory, training, and bureaucratic limitations, the mass exercises played a pivotal role in confirming the necessity of deploying tanks alongside infantry as a combined arms force. Anti-tank guns were verified as an effective countermeasure to armored vehicles. Air-ground integration, despite an initial Army Air Corps bias towards high-altitude precision daylight bombardment, was shown to have value. Perhaps most importantly, the Louisiana Maneuvers confirmed — to Americans, allies, and adversaries alike — that a ragtag group of “civilians in khaki pants” had been molded over the previous two years into a fighting army. While not a panacea, the maneuvers, in short, were the denouement of the U.S. Army’s pre-war mobilization.



From the meticulous drills or “bloodless battles” of ancient Roman legionaries to the tabletop Kriegsspiel of Georg von Reisswitz and the more recent use of distributed, virtual, and constructive training architectures, the act of simulating war — whether through maneuvers, exercises, or wargames — has long constituted an invaluable means of training, experimentation, and signaling. In the absence of combat, simulations like the Louisiana Maneuvers can root out weaknesses, refine concepts and technologies, and acclimatize troops to the complex and varied physical realities of the battlefield. They can also allow users to transcend their current realities, ideally by helping them to question and assess those “known unknowns” (and potentially those wicked “unknown unknowns”) that may radically alter the future battlespace. For these reasons, simulation has been touted as a key avenue to imagine and prepare for the contours of future conflict.

As the United States attempts to articulate “a new American way of war” to better meet the exigencies of great-power competition, the Louisiana Maneuvers — in their scale, scope, and sophistication — can provide contemporary defense planners with a number of valuable and enduring insights. Indeed, beyond providing a clear demonstration of the benefits of peacetime experimentation and innovation, the Louisiana Maneuvers highlight the importance of new ways of thinking and far-reaching structural reform when facing formidable peer competitors and rapid alterations in the combat landscape. Just as the U.S. military innovated in the face of technological change during the interwar years, the United States should once again change to better leverage digitally enabled technologies that may prove transformational today. Eight decades on, the Louisiana Maneuvers provide three abiding lessons: first, the need for personnel reform when confronted with a radically altered battlefield landscape; second, the importance of mission-driven acquisitions to incorporate the best available private sector innovations in the Department of Defense; and finally, the game-changing role of simulation to drive reform in change-resistant bureaucracies.

Prevailing in the Wars of Tomorrow Requires Broad-Based Personnel Reform

Gen. George C. Marshall was sworn in as the U.S. Army’s chief of staff on Sept. 1, 1939, the same day that the Wehrmacht invaded Poland in a spectacular show of coordinated offensive force, signaling the start of World War II. Marshall had inherited a hollow and disorganized land force. Anemic levels of defense appropriations in the interwar period, when coupled with strong isolationist sentiments in certain quarters of Congress, had reduced the military to a husk, or as Marshall later characterized it, that of “a third-rate power.” Conscious of the enormity of the task that lay ahead, the new army chief immediately sought to correct deficiencies across manpower and weaponry, casting an especially critical gaze over the service’s leadership.

Still haunted by his experiences in World War I — particularly the gross failures of leadership and the resultant slaughter during the initial phases of the Meuse-Argonne campaign — Marshall kept a little black book in his office desk. The book, which he once waved at reporters to prove its existence, recorded Marshall’s thoughts, both favorable and unfavorable, on individuals within the Army’s leadership core. Marshall’s goals were simple, albeit ruthless — cull those leaders lacking skill or whose views and methods were anachronistic while promoting those he deemed best suited to meet the changing character of warfare. With the support of President Franklin D. Roosevelt, Marshall devised a scheme whereby certain underperforming senior officers would be winnowed out of the ranks. Field exercises, and in particular the Louisiana Maneuvers, were at the heart of this process.

Unlike many of the training exercises held in 1939 and 1940, the 1941 Louisiana Maneuvers were unscripted: Commanders were granted full flexibility to plan and operate as they deemed fit. The sheer scale of the exercise stressed the importance of maneuver, communications, and logistics, alongside tactical acumen and operational brilliance. General officers were given a range of capabilities — artillery, infantry, armor, aircraft, and even paratroopers — to assess their ability to command and control the full suite of assets at their disposal. Commanders were also on notice. Just days before the first maneuver, hundreds of active-duty, reserve, and guard officers (some of whom were politically and socially well-connected) were dismissed for underperformance. Future military employment was contingent on achievement.

Marshall also placed an emphasis on fidelity. He sought to mimic the demands and intensity of future European or Asian theaters, without the use of live ammunition. Loudspeakers were carted onto the maneuver grounds to reproduce the sounds of battle — the rattle of the machine gun barrage and the deafening roar of artillery. Smoke cannisters shrouded the battlefield in a thick haze in an effort to stress commanders and warfighters. Aircraft and cannons employed flour bags to simulate munitions. Bursting open in dull thuds, they caked bridges and vehicles in a wintry frosting, providing a strangely ethereal visual demonstration of putative blast radii. The terrain and weather only served to heighten the fog and friction of warfare. As one veteran of the 1940 series of exercises noted, “in addition to the enemy there are two redoubtable antagonists lurking … to break up the best laid plans of a commander — Old Man Fog and his twin brother Bog.” General officers who flourished under these conditions — demonstrating a masterful capacity to shape and transform warfighting practices — were singled out for future promotion. Indeed, future military giants such as then-Col. Dwight D. Eisenhower and then-Brig. Gen. George Patton first gained acclaim during the Louisiana Maneuvers before achieving renown in combat in World War II.

At times these attempts at fidelity bordered on the farcical or the absurd. After an umpire ruled a bridge had been destroyed, a corporal and his squadron, after briefly hesitating, walked confidently across. The umpire, startled at such a flagrant violation of the rules, yelled, “Hey, don’t you see that bridge is destroyed?” To the irritation of the umpire, the corporal caustically replied, “Of course I can see it’s destroyed, can’t you see we’re swimming?” Locals acted as spectators, watching as soldiers engaged in hand-to-hand combat on their front lawns, and, in at least one instance, attempted to covertly join the action by employing a toy cannon and fireworks, in what later became known in jest as the “Battle of Bermuda Bridge.” The grueling training, when juxtaposed against some of these more whimsical elements of the maneuvers, cemented an early GI culture among the troops while also building morale — a key component of battlefield effectiveness.

Marshall used the Army’s pre-mobilization exercises — which would include the Louisiana Maneuvers — to fundamentally transform the service’s promotion practices. While at times imperfect and incorrect in his assessments of character and capability, Marshall sought to elevate a new cadre of leaders solely based on merit. To the chagrin of some of his contemporaries, he also radically reconstructed officer education, championing what would become the scaffolding of today’s officer candidate school program. Indeed, more than solely highlighting the men best fit to lead, Marshall sought to demonstrate and instill those characteristics needed to triumph on future battlefields — initiative, creativity, agility, adaptability, and foresight.

The U.S. military is not in need of a draconian leadership overhaul along the lines of the interwar Army: Innovative thinking remains widespread across many areas. However, if the United States is to prevail in a protracted competition with China and Russia — particularly one that increasingly manifests across multiple domains, including space and cyber, and in nebulous gray zones — recruitment, personnel, and promotion practices will require further reform. This is not a novel argument. The 2018 National Defense Strategy sees personnel not solely as a quantitative measure of end-strength, but as a critical asset — or “workforce talent” — that undergirds a more creative, agile, and lethal force. To that end, promotion practices, like the “up or out” system under the Defense Officer Personnel Management Act, have been singled out for reform. Professional military education, after a period of relative stagnation, is now in the midst of a radical overhaul. The military has changed recruitment practices in an effort to attract the technical talents who will enable a more informationized force, among them network architects, artificial intelligence developers, hackers, electronic warfare operators, and software developers, among others. These are all positive steps, but without associated culture change — and arguably broader structural change akin to that pushed by Marshall in the interwar years — these reforms may still fall short of what is required to preserve the U.S. military’s qualitative edge in an era of digital warfare.

Private Sector Innovation and the Power of Mission-Driven Acquisitions

In early 1941, three aviation firms — Piper, Aeronca, and Pipercraft — approached the Army with an offer: the use of 11 of their Club-type sports planes, flown by factory pilots for the summer maneuver season, and all paid for by the manufacturers. At that time, organic aviation (i.e., the assignment of aircraft and personnel to the ground forces mission) had yet to become a fully matured mission, complete with doctrine, organizational support, proper training, and platforms. Falling victim to the vicious bureaucratic infighting between the Army Air Corps and the Army Ground Forces on the employment of airpower in war, aerial observation had been relegated to “orphan status” within the force, devolving into an “intellectual and professional backwater.” However, a confluence of factors — from equipment failures to the canny bureaucratic maneuverings of air observation enthusiasts and the fielding of FM radios for air-ground integration — created an opening for the aviation firms to press their case. The firms hypothesized that their Club-type aircraft could support artillery spotting and liaison missions and thereby sought to encourage test and experimentation in the field. The offer of free support proved too attractive to resist. The Army agreed to test and experiment with the companies’ aircraft in the lead-up to the 1941 maneuver season in Tennessee.

Affectionately called “grasshopper planes” during the maneuvers for their appearance when landing, the light liaison aircraft were an immediate test and experimentation success — acting as useful assets for intelligence, surveillance, reconnaissance, transport, and the direction of artillery fire. At approximately one tenth the cost of a normal observation aircraft, the nimble, commercial two-seater plane was easy to maneuver and handle. The planes could land on nearly any level surface, from fields to narrow dust-ridden roads and muddy pastures, while also proving easy to conceal and maintain when not in use.

After proving their worth in Tennessee, the aircraft were employed throughout the maneuver season, earning their own insignia — a flying grasshopper casually smoking a cigarette. Indeed, in a nod to their battlefield effectiveness, Patton acquired his own light plane to control his troops in mock battle from the air. Using a loudspeaker mounted on his aircraft, Patton, when dissatisfied, would belt out a string of profanity-laced commands — verbally pummeling the men below him into action — all much to the amusement of local spectators. The planes proved so beneficial for command and control that umpires barred pilots from flying midway through the maneuvers to better level the playing field.

By the close of the maneuvers, the grasshoppers had logged a combined total of 3,000 non-combat missions flying over 400,000 miles, without the loss of a single sortie. The grasshoppers’ battle- worthiness motivated the War Department to acquire, and thereby order, that six to 10 light aircraft be assigned to every Army division for the purposes of spotting and general liaison. The grasshoppers are the antecedents of today’s Army aviation. However, today, the grasshoppers would stand little chance of being acquired by the Department of Defense.

Despite the best attempts of our defense acquisition system to work more closely with private industry — from the Defense Innovation Unit to the Defense Innovation Board and AFWERX — the acquisition system remains a byzantine process. It is riddled with thorny policies and regulations, over-classified to the point of absurdity, and beset by parochial interests. The system can prove impenetrable to even the savviest of new entrants. Complicating this opaque and labyrinthine process are defense requests for proposals, which have acquired a certain notoriety as jargon-laden consensus documents often beset by hundreds of pages of requirements, even for fielding something as seemingly simple as the Army’s new pistol. In such a system, it is difficult to imagine the grasshopper aircraft being down-selected for test and experimentation, let alone meeting the often rigidly defined platform requirements. Indeed, prior to the sport plane’s field tests, some military aviators had expressed an aversion to the aircraft, viewing the technology as obsolete compared to other contemporary and allegedly more cutting-edge aircraft. 

The agile grasshoppers ultimately deployed to Europe — recording, quite remarkably, one of the final air-to-air kills — largely because the Army had sought a mission-driven, platform- agnostic solution to the air observation challenge. This form of pragmatic, bottom-up change runs counter to most acquisition policy today. The Department of Defense rarely releases mission-focused requirements or employs mission-driven competitions as the basis for acquisitions. Reforming the present U.S. acquisition system would require significant structural change, yet expanding mission-driven capability and concept discovery opportunities to accommodate the “grasshoppers” of the future is a necessary and incremental first step.

Simulation Can Empower Organizational Reform in Change-Resistant Bureaucracies

On May 25, 1940, a group of Army officers — including Patton, then-Brig. Gen. Adna R. Chaffee Jr., and Gen. Frank Andrews, among others — clandestinely gathered in a high school basement in Alexandria, Louisiana. The participants’ goal was to separate tanks from the infantry and horse cavalry, thereby creating a separate mechanized branch like the Germans’ powerful Panzer division. Noticeably absent at the meeting, despite being in the vicinity, were the chiefs of both the cavalry and infantry. The meeting participants, later labeled “the basement conspirators,” had witnessed the stunning assault by armored forces on Leesville during the maneuvers and were now convinced that the Army, and in particular the mechanized forces, was in dire need of reform. However, they faced fierce resistance from both the infantry and the cavalry, two branches that favored the status quo and opposed the further expansion of armored forces.

Previously, the National Defense Act of 1920 had placed tanks under the control of the infantry “to facilitate the uninterrupted advance of the rifleman in the attack.” Infantry doctrine called for tanks to advance slowly behind a curtain of artillery fire, targeting enemy antitank positions — an anachronistic tactic reminiscent of World War I trench warfare. The cavalry, to get around the restrictions of the National Defense Act, acquired tanks as “combat cars.” While the cavalry’s use of tanks was slightly more innovative than the infantry’s — experimenting with tanks in a combined arms force — the branch overwhelmingly favored its equestrian units. As the chief of the cavalry had stubbornly griped, “mechanization should not come at the expense of a single mounted regiment.”

Reforming the Army to better accommodate and experiment with changes in mechanization was no easy task. Security studies scholars have long sought to shed light on the many challenges linked to organizational change within defense organizations. Defense bureaucracies, by nature, are often ponderous, slow-moving beasts. The “basement conspirators” also risked sabotaging their own careers through their advocacy of reform. Even Eisenhower, who was not present at the meeting but had similar ideas, was persuaded to keep them to himself, noting, “I was told that my ideas were not only wrong but dangerous. … Particularly, I was not going to publish anything incompatible with solid infantry doctrine. If I did, I would be hauled before a court-martial.”

The pre-war mobilization exercises, which would include the 1941 Louisiana Maneuvers, provided a way forward for innovation, supplying the “basement conspirators” and Army leadership concrete evidence that current mechanization and equestrian practices were antiquated and in desperate need of reform. Indeed, horse cavalry, despite the best efforts of equestrian units in the field, had clearly lost their superiority in mobility. In one striking example, a National Guard division had to abandon its rented horses in the field due to the animals’ state of exhaustion. When given the choice between horse-mechanized reconnaissance regiments and purely mechanized reconnaissance, divisions selected the latter.

After the infamous basement meeting, Andrews delivered the recommendations to Marshall, who subsequently stood up an autonomous armored force under the command of Chaffee. While not all of Chaffee’s ideas for armored warfare bore fruit, the advent of independent tank units incentivized deeper tactical and operational experimentation, including Patton’s famous armored, blitzkrieg-style hook through Texas, which he later emulated in the Battle of the Bulge. To the chagrin of many mounted troops, by the close of the Louisiana Maneuvers, equestrian units were retired completely from service. As Gen. Joseph Stilwell sarcastically stated, when asked the role of horses in future war: “Good eating, if you’re hungry.”

Much like the interwar debates on the future of U.S. mechanization and horse cavalry, the United States is at a critical juncture as it reimagines its future force. After the United States invested in a small number of exquisite manned platforms for decades, some defense analysts are now calling for a reconceptualization of America’s military posture, towards one focused on mass, autonomy, survivability, or expendability. Others have characterized the change as an evolution of a hardware-centric military to a software-centric force — a transformation from platforms to kill chains. Such a change will not come easily. Indeed, just as in the interwar years, entrenched interests will favor the status quo. Simulation, whether in the form of wargames or large-scale exercises like those in Louisiana, should provide a way forward, particularly for those thorny challenges that will likely require a fundamental realignment of the future force.

Change is underway, and the services do see simulation, testing, and experimentation as a way forward. Indeed, new efforts, like the Army’s Project Convergence, have been described as “this generation’s Louisiana Maneuvers,” now optimized for the information age. However, broader structural challenges will plague the force, particularly as it conceptualizes how to fight for joint all-domain operations. At present, the Defense Department has largely hollowed out its capacity to conduct large-scale joint experimentation. No agency, activity, or joint function currently has clear responsibility for joint concept development and experimentation. Moreover, investments in the types of environments (i.e., virtual and constructive) that will facilitate experimentation across multiple domains remain largely at a nascent stage of development. The United States no longer requires the physical troop co-location or mass mobilization of the Louisiana Maneuvers for experimentation. However, it does need to more broadly invest in the synthetic environments, such as the Army’s Synthetic Training Environment, that will empower virtual co-location, concept development, and experimentation, particularly when conceptualizing how to integrate cyber and informationized capabilities alongside artificially intelligent systems.

Looking Back to See Ahead

It is impossible to delineate with absolute clarity the contours of the future battlespace. Yet, there are methods by which a more informed prediction may take place. As Frank Hoffman has wisely noted, “A military that does not balance looking backward with constant glances at the future risks preparing only for the war last fought.” Simulating war — whether through board games or virtual simulations — has long enabled strategists to better imagine the future combat environment and consequently create conditions for much-needed structural change. While the U.S. Army still had to undergo profound organization learning throughout World War II, the Louisiana Maneuvers did act as a useful data point in that process. Indeed, the Louisiana Maneuvers highlight the innovative potential of peacetime experimentation and innovation when confronting formidable peer competitors and rapid changes in the combat landscape.

As the United States seeks to reposition itself to better meet the exigencies of great-power competition, it may be time to once again dust off lessons learned from those grueling exercises held in the interwar years.



Jennifer McArdle is a product strategist at Improbable LLC and an adjunct senior fellow at the Center for a New American Security.

The author thanks Lt. Gen. (ret.) Tony Ierardi for his thoughtful comments and feedback throughout the drafting of this piece.

Image: Curtis Wright Maps