Out-Adapting the Enemy: Why Mass Alone Won’t Win Tomorrow’s Wars

Commentary by Benjamin Jensen

Published July 11, 2025

Next Army is a collaborative series by CSIS Futures Lab and the Modern War Institute launched in honor of the U.S. Army's 250th birthday and the Army Transformation Initiative (ATI). The commentaries explore how emerging technologies, organizational reforms, and major shifts in the strategic environment will shape the force of 2040 and beyond.

In the future, the U.S. Army will field modular systems of drones and loitering munitions alongside electronic warfare and intelligence collection kits that can be tailored to the mission at the tactical level. Soldiers will tinker and adapt, creating unique mosaic effects that enable more rapid adaptation at lower echelons. Grenades will be thrown, fired from a rifle, or dropped from a drone. Sensors will be distributed forward as digital sentries, mounted on small drones, or used to augment crew-served weapons. Entire remote weapons pods will be swapped between unmanned vehicles depending on the mission and threat profile. The resulting flexibility will create a new form of lethality since war, as a complex system, requires constant adjustment to changes in the operational environment.

War is defined by what J. F. C. Fuller called the constant tactical factor. Every adaptation on the battlefield begets a counter-adaptation. This dynamic creates an imperative to build forces built to maximize adaptation and a family of systems that support prototyping and rapid adjustments on the frontlines. The trend towards smaller, commercial sensors and software packages reinforces this dynamic. It is now cost-effective to build adaptable systems at the company level, but doing so will require a fundamental cultural change and policy reforms.

Specifically, commanders will need to be allowed to assume more risk in training, and existing training areas will need to accommodate more live fire exercises that include small drones operating in the air littorals. Industry will need to participate in these exercises using contract procedures that allow them to support prototyping warfare and constant adjustments. Last, the Army will need to ensure provisions are in place within its contracts to allow units in the field to tinker with equipment and reduce the reliance on field service engineers.

The Logic of Adaptation

For too long, equipment has been given to soldiers with the expectation that there should be few to no adjustments. Soldiers fire javelins. They don't modify them. This rigidity makes the force brittle to enemy adaptation. If you optimize to find one signature-say the thermal image of a tank or the electronic signature of a command post-and the enemy correctly masks it, you are blind.

This is not how modern land armies gain an advantage. Across the frontline in Ukraine, there is a constant cycle of learning to mask signatures and spoof sensors with decoys alongside daily adjustments to drone strike missions. This cycle of learning requires each side to continually adjust how they hunt the enemy, putting a premium on low-cost sensors stitched together in creative combinations and constant adjustment to electromagnetic spectrum operations. Adaptation is how forces survive and increase combat power in modern war. The entire process is similar to literature on horizontal innovation, which focuses on how units adapt and share insights (i.e., lessons learned) to increase combat power in other units. In other words, it is not enough to have more stuff to win modern battles. Mass helps but is only efficient and truly disruptive when it is used by a thinking army with a culture of bottom-up adaptation.

This logic stands in contrast to the current programmatic model for building and fielding equipment in the military. In this model, staff officers try to imagine a wide range of scenarios and use them to generate capability requirements. It is effective, but slow. This process tends to overfit the capability and increase the cost while closing off a culture of tinkering and adaptation. That makes sense when it's large end items, which the programmatic process historically supports. It makes no sense when the most lethal weapons on the battlefield are loaded with commercial-off-the-shelf components and adapted daily.

As seen in Ukraine, adapting new approaches to integrating small drones is a process that, by design, must be efficient and fast. There are no perfect solutions, just partial bets violently executed and studied to determine what to build. In an interview, the head of a drone battalion summarized the unit-level adaptation process this way:

[When] we receive the drones. We send them to our workshop to be worked on by our specialists. This has now become a complete must for us. Any freshly manufactured drone still has to be refined by our specialists, because a newly manufactured drone is frequently inefficient. After our specialists work with our drones, we transport them directly to the positions where our pilots test them once more, because there can be some malfunctions due to the transportation, conditions, etcetera, etcetera. We need to make sure that the drones are completely operational.

This process is augmented by a culture of daily after-action reviews to adjust tactics and even modify drone components. Furthermore, Ukraine is using creative methods to directly link battlefield performance and unit-level requests to its defense industrial base to optimize the delivery of drones. The case should become a core feature of how the U.S. Army thinks about how to adjust its programmatic culture and collapse processes for developing equipment and tactics into a tighter feedback loop.

Adapting capabilities and tactics to the mission, enemy, troops, terrain, time, and civil considerations (METT-TC) allows smaller forces to fight outnumbered. They tailor effects and sequence tasks to increase combat power. By using low-cost drones and sensors integrated with existing munitions, this process creates, in effect, adaptable mass and changing attack profiles that keep the enemy off balance, producing what Mic Ryan calls a drone wall and a stalemate few would have imagined when the war began. As a result, it is not just enough to outbuild your opponent (i.e., mass); you have to set the conditions to out-adapt them, embracing Fuller's constant tactical factor.

Building Adaptability into the Army

The U.S. Army has a solid foundation for adapting company teams, battalion task forces, and even larger combined arms brigades. What it lacks is the equipment and culture that lends itself to the type of constant tinkering that allows outgunned and outmanned Ukrainian forces to hold the line. Adaptability must become a system feature in the U.S. Army. For too long, the expectation is that any sergeant can cobble together ingenious kit like the hedgerow clippers of Normandy fame. Highlighting heroes is a false promise, absent significant shifts to how the Army trains and procures equipment. Worse, most modern weapon systems aren't built to allow end users to make adjustments, creating a brittle system with long, slow feedback loops.

Building the next army around the concept of adaptability requires fundamental shifts in policy and culture. First, the U.S. Department of the Army should explore how to rewrite contracts and accelerate the capability analysis process to support adaptable mass. This approach would allow users more flexibility to test, modify, and refine equipment, giving soldiers agency in the engineering process. While the Army has successfully used large-scale, iterated experiments like Project Convergence as a bridge to this future, they don't go far enough. Adaptability has to be a core design tenet that allows soldiers to adjust weapons, sensor payloads, and even run different software scripts to maximize lethality. That requires a more networked approach to industry participation and faster feedback loops. In the extreme case, like Ukraine, this would include swapping out payloads on drones operating in the air littorals and the ability to adjust how different pieces of equipment interact in the electromagnetic spectrum.

Second, there will need to be investments in training infrastructure, including virtual, and ranges that support creating a culture of adaptable mass in unit exercises. This will require more than money. It will also require more creative task standards for units so that they can explore different solutions to common tactical problems as opposed to just demonstrating proficiency against a mission-essential task list. Commanders should be evaluated on how well they analyze and adapt to common tactical problems, not just how well they follow textbook solutions. Soldiers should be judged by their ability to improvise novel solutions. This will require changing the training culture and how the army approaches risk. It also requires a more robust simulated training environment similar to ideas outlined in the Army learning concept. In the ideal case, these shifts to training will focus on a fight club model and letting units fight each other. Adaptation is more important when fighting another thinking organization.

Benjamin Jensen is the director of the Futures Lab at the Center for Strategic and International Studies in Washington, D.C.

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