The Will to Fight and the Fate of Nations


“Distilled to its essence, war is a violent struggle between two (or more) hostile and independent wills, each trying to impose itself on the other.”

“[War] is mostly a matter of wills…Whose will is going to break first? Ours or the enemy’s?”

There is a dangerous misalignment between American theories of war and American military practice. This startling conclusion is apparent after two years of researching the will to fight on behalf of the U.S. Army.

America’s military argues that “will to fight” — the disposition and decision to fight, act, or persevere — is the most important factor in war. In this view, war is a fundamentally human endeavor. Military force is used to bend and break the enemy’s will. This view is entirely correct, but in practice, America’s military tends to treat war as a fundamentally mechanical process, driven by acquisitions and technology.

This gap between theory and practice undermines military effectiveness. It generates dangerous and false assumptions about adversaries, allies, and even about American fighting power. Failure to understand will to fight has led to both tactical and strategic failure in war.

Thankfully, this is a problem with a reasonable and achievable solution. America’s military can effectively improve its understanding of will to fight in order to help break adversaries, shore up allies and partners, and improve American combat effectiveness. Our reports on the will to fight of military units and organizations and national leaders offer starting points for a change that is needed — and that can be implemented — immediately.

The Problem: American Military Reluctance to Embrace Human Complexity

Understanding human behavior is difficult. There is a powerful American cultural imperative to view war primarily as a mechanical problem. The human element is held aloft in military history, theory, and doctrine, but it is too often downplayed or ignored in practice.

America’s military services typically view war as a contest of opposing, independent gear. Some present American conceptualizations of war as redolent of the worst excesses of the “revolution in military affairs.” In this aspirational and pristine vision of modern warfare, tanks fight tanks and planes fight planes in an anthropomorphic clash of metal. Technology and comparative tables of equipment dictate official predictions for wars’ outcomes.

This dynamic may be most obvious in military war games and simulations. Most are bereft of the human element. Simulated soldiers march sharply into withering enemy fire, obeying even the most reckless orders without hesitation or deviation. This gives war games and simulations a glossy veneer of mechanistic neatness that all but ignores historical experiences with warfare and human behavior. The breaking of the adversary’s will is rarely a central design consideration.

Games and simulations can help senior policymakers think about the likely outcomes of future wars, but they can cause more harm than good if they treat the profoundly human endeavor of war like an episode of BattleBots.

Marine Corps capstone doctrine argues that this anthropomorphic construct represents a fundamentally inaccurate understanding of warfare. The doctrine states that violence is an “essential element of war.” It goes on to state that concepts of war that neglect the impact of the human will are “inherently flawed.” This theme dominates Marine thinking on war:“[T]he human dimension is central in war. No degree of technological development or scientific calculation will diminish the human dimension in war.”

Recent Army thinking on will to fight makes a similar case. The Army argues that, “Fundamentally, all war is about changing human behavior.” The consequences of ignoring these arguments can be severe. Failure to appreciate will to fight can and sometimes does contribute to tactical or strategic defeat.

This unrealistic thinking undermines analysis of adversaries, allies and partners, and American military forces. Thousands of historical and prospective cases apply. We present two here: Iraq and Russia.

The Shattered Will of a Partner: Iraq in 2014

Iraq has shown us just how costly the failure to understand partner will to fight can be. In 2011, the United States withdrew its military forces from Iraq. Official American assessments claimed that the Iraqi army was ready to take over the responsibility for securing Iraq. Secretary of Defense Leon Panetta declared: “we salute the fact that Iraq is now fully responsible for directing its own path to future security.” At the same time the head of the Iraqi army argued that the Americans were leaving too soon.

Less than three years after the last American military unit left Iraq, a few thousand lightly armed Islamic State fighters routed the American-trained, American-equipped, mechanized, combined-arms Iraqi army, shattered four of its divisions, and seized one-third of the country. Secretary of Defense Ashton Carter correctly observed, “The Iraqi forces just showed no will to fight.”

Arguably this was an endemic problem in Iraq. After the 2014 debacle, American leaders were drawn back into a war they believed they had ended with a strategic victory. Nearly five years after the Iraqi collapse and 15 years after the coalition invasion of Iraq, approximately 5,000 U.S. troops are still there working to shore up our partner force.

What Do We Really Know About Russian Will to Fight?

Russia has built up a formidable military capability along NATO’s eastern flank. Potential solutions to the growing Russian threat have centered mostly on building physical capabilities: more and better armor and aircraft, more and better missiles and rockets, more and better cyber and electronic warfare. Concepts of victory hinge on achieving physical and technological overmatch. Many, and arguably most, threat analyses simply assume Russian forces have extraordinary will to fight. Few question Russia’s fighting spirit.

There is no question that physical power is essential to military success. Russia’s modern army is increasingly formidable. But for all of Russia’s legitimate physical capabilities, its fundamental strengths and weaknesses lie in the minds of its soldiers and leaders.

Russia propagandizes a façade of invincibility. Many are convinced by imagery of steel-hearted Russian soldiers. One senior American leader recently told us that, “Russians never break.” But the last time Russia was in major, extended combined-arms combat against a near-peer foe was in 1945 against Japan in Manchuria. Recall that over five million Soviet soldiers were taken prisoner in World War II. Just this year, elite Russian Wagner Group mercenaries fled the battlefield in Syria after tasting American firepower. Russians are not combat gods. They do break.

If Russians can be broken, can we rethink the nature of the threat they currently pose? Consider a notional Russian invasion of Eastern Europe, a scenario now worn thin with mechanistic analyses. In this context, Russia’s new anti-aircraft missiles, modern battle tanks, and fifth-generation jets are intimidating.

But Russia’s “game changer” S-400 missiles only work if their operators stay at their stations while U.S. anti-radiation missiles home in on them from above. At the tactical level of warfare, Russia’s impressive new Armata T-14 tanks are only intimidating if their tank commanders have the will to roll forward into the dangerous envelope at the front edge of their own air defense umbrella. Russia’s new Sukhoi Su-57 fifth generation fighter-bombers are only dangerous if their air commanders have the will to send them into the teeth of deadly alliance fighter screens, and if the pilots have the will to follow orders.

Human strength and vulnerability are equally relevant at the national level of war. President Vladimir Putin is only as dangerous as his will to fight, and everyone has a breaking point. Putin’s cost-benefit calculations can be shaped to influence him away from conflict. Given the right mix of allied actions he could be made to back down in the midst of a prospective war. Key factors in Russian national will to fight might be popular support, or casualties, or internal government divisions, or some complex mix that can be assessed and acted on.

Will to fight shapes aggression. Aggression feeds tempo. Tempo determines timelines. If Russian tactical and national will to fight can be undermined then a notional Russian advance into Eastern Europe can be slowed, giving time to organize NATO defenses, shear away Russian air defenses and fires, and perhaps stop the Russians cold. This will require deep, factor-by-factor analysis and a finely-tuned mix of kinetic and non-kinetic actions, including fires, maneuvers, psychological operations, information activities, cyber attacks, sabotage, and any other tool in the allied military and national inventory that can be applied to shape Russian thinking and behavior.

Overmatching Russian mass and equipment is one part of a more complex and important pathway to overmatching the Russians. It is worth repeating that Russians — and Chinese, Iranian, and North Korean soldiers, sailors, airmen, and political leaders — can be broken. The U.S. military simply does not devote enough attention to understanding how to break them, or at least erode their resolve, in order to make war less likely and to make our success in war more likely and less costly.

No Definition, No Model, No Tools, Limited Action

Something is missing. Most obviously, there is no joint force definition of will to fight. Definitions don’t solve problems; sometimes, they make them worse. But the lack of even a half-hearted guess at the meaning of will to fight leaves the U.S. military with no central point of reference.

In the Department of Defense, definitions shape authorities, anchor training and education, and guide spending. Absence of a definition strongly suggests that will to fight is unimportant and impractical. Lack of emphasis shows in practice. Scratch the surface in doctrine and field manuals — after getting past the first few capstone pages — and will to fight all but disappears as a warfighting factor.

There is no joint force model of will to fight that might support analysis or assessment. By model, we mean a conceptual model to help leaders, analysts, and advisors think about, improve, and exploit will to fight, rather than a complex input-output machine. Right now there appears to be no structured, practical guide to help anyone in the military think through the factors that influence will to fight.

Some military leaders see this gap. In 2016 the Joint Chiefs of Staff published the Joint Concept on Human Aspects of Military Operations. The Joint Chiefs argue that the U.S. military has a poor understanding of will to fight. They recommend improving the understanding of will to fight and developing the abilities to influence allies, populations, and adversaries with kinetic and non-kinetic actions.

U.S. Army Special Operations Command recently proposed the concept of cognitive maneuver. Their central argument is that the joint force needs to “maneuver toward cognitive objectives,” which means finding ways to change human behavior by changing minds through a tailored combination of force and influence.

Adding will to fight to any plan or forecast will almost certainly lead to different assumptions about combat and the art of war. Improving the accuracy of military assumptions will help improve training, education, information operations, intelligence collection, security force assistance, planning, and operations. It can be used immediately to reduce acquisitions cost and improve deterrence. As we argued above, these concepts can be quickly and effectively applied to adversaries. They can and should be applied to partners, allies, and American forces as well.

Immediate Relevance: Global Partners and Allies

A concrete, practical, and analytically defensible definition, model, and tool could be applied to great effect to help ensure America’s global alliances and partnerships bear fruit. Iraq proved that America cannot always count on its partners to fight. Since 2014, the United States and its allies have done a great deal to shatter the Islamic State’s military forces and bring some spirit and discipline back to the Iraqi security forces. But what will happen to the Iraqis if we withdraw again? How dependent have we made them on U.S. air support and intelligence, and what might these dependencies mean for will to fight in the future?

Many talented American advisors have sought to understand and influence partner will to fight. But experiences in Vietnam, Yemen, Afghanistan, the Philippines, and other places where the United States counts on partner forces suggest mixed results and a lack of consistent, structured understanding of the will of partner forces.

In Europe, some allies that could once be counted on to defend against Russian aggression as near peers today field small and often poorly equipped forces. Like the Russians they would have to face in a notional war, most European soldiers have no major combat experience against a combined-arms national joint force. Would they fight? If so, how aggressively? Might they break? Would national leaders waver or commit forces? What are the factors that might cause them to waver, or that might be shored up to keep them in the fight? Narrowing the gap in our planning assumptions is essential to war planning, training, and even acquisitions.

Looking Inward: American Will to Fight

As uncomfortable as it may be, American military leaders from all services should also consider the will to fight of their own forces. Americans fought against a weak Iraqi conventional army in 2003. They have fought consistently and fought hard against irregular forces around the world since 2001. But American ground forces have not been attacked by enemy aircraft for decades. No Americans in uniform today have fought through the kind of sustained artillery, rocket, and missile fires that the Russians, Chinese, North Koreans, or even the relatively less capable Iranians could muster. American air forces have not suffered significant casualties since the Vietnam War. America’s Navy has not suffered mass surface or sub-surface combat casualties since World War II.

American military leaders emphasize components of will to fight — cohesion, aggression, tough training, resilience, etc. — perhaps more than any other military leaders in the world. But is American will to fight sufficient for the battles to come? How dependent have American soldiers become on ‘golden hour’ medical evacuation, a service that probably will not exist in an all-out war with Russia. How will social media affect America’s collective ability to sustain casualties? How can, and how should, American will to fight be assessed and improved? The Close Combat Lethality Task Force seeks to analyze these questions for small unit infantry forces, but a joint solution does not yet appear to be in the making.

Improving Understanding of Will to Fight and Making It Practical

Our reports on the will to fight of military units and organizations and national governments analyze these gaps and propose starting points for solutions. Remedy comes in the form of proposed universal definitions, exploratory models for assessment and analysis, and practical tools to help understand and influence will to fight.

Perfect accuracy is unattainable. No one will never be able to precisely and accurately predict human behavior. Even so, the U.S. military and its allies can significantly improve their understanding of will to fight. Specifically, they can quickly and effectively improve their understanding of the disposition to fight, and the factors that influence disposition. They can use this knowledge to sharply improve American and allied chances of success in any war.

This is not about quantifying human behavior, nor is it about winning wars without fighting. Instead, it is about the American military buying in to its own theories and doctrine. Applying will to fight concepts means finding more efficient, expedient, and effective ways of succeeding in — and possibly even preventing — wars.

Failure to center attention on will to fight now will increase the chances of military failure in future wars. The United States is making some huge bets on military technology and gear. Tech matters. Gear matters. Both gear and tech affect will to fight. Yet it is the relative strength and frailty of human beings — augmented by gear and tech — that most influence the outcomes of wars. As Võ Nguyên Giáp, wartime commander of the People’s Army of Vietnam, said, war is about “Human beings! Human beings!”


Ben Connable is a senior political scientist at the non-profit RAND Corporation.

Michael McNerney is a senior international defense researcher at the non-profit RAND Corporation.

This article is derived from research that is fully documented in two RAND reports: Will to Fight: Analyzing, Modeling, and Simulating the Will to Fight of Military Units (by Ben Connable, Michael J. McNerney, William Marcellino, Aaron Frank, Henry Hargrove, Marek N. Posard, S. Rebecca Zimmerman, Natasha Lander, Jasen J. Castillo, and James Sladden) and National Will to Fight: Why Some States Keep Fighting and Others Don’t (by Michael J. McNerney, Ben Connable, S. Rebecca Zimmerman, Natasha Lander, Marek N. Posard, Jasen J. Castillo, Dan Madden, Ilana Blum, Aaron Frank, Benjamin J. Fernandes, In Hyo Seol, Christopher Paul, and Andrew Parasiliti).

Image: Russian Ministry of Defense