Two years after the release of the National Defense Strategy, the Pentagon has issued a declassified summary of its Irregular Warfare Annex. The seven-page text details how the Department of Defense seeks to institutionalize and operationalize this form of warfare amid the ongoing recalibration of DoD’s focus on peer and near-peer adversaries. As this is the document’s only annex, advocates of irregular warfare are hopeful that it will generate momentum similar to the defense strategy itself, which since 2018 has made headlines by shifting US strategic priorities away from counterterrorism and toward great power competition.

The focus on irregular warfare is certainly overdue. It is not just that the United States has struggled to understand the “indirect and asymmetric approaches” of irregular adversaries, both state and nonstate, but that it has paid insufficient attention to the related problems of “influence and legitimacy”—the defining concerns of irregular warfare. The right to lead is the central prize in irregular competitions; it was fundamental to the confrontations in Iraq and Afghanistan and has since returned, with a vengeance, to threaten America’s position globally.

The IW Annex is therefore a step in the right direction, but it is also inadequate in the face of the challenge at hand. The history of attempted reforms in this area suggest the unlikelihood of any one document jolting the United States into acknowledging or readying itself for the full depth of irregular warfare. In the first place, the reform effort must confront the cultural opposition of the Department of Defense; on this front, the very placement of irregular warfare as an annex is telling. Second, irregular warfare must travel beyond the Pentagon’s endless corridors and reach areas of government, even society, where it currently has no traction. Most critically, the United States today lacks the purpose, resilience, and capabilities required to compete effectively for global leadership. This competition for legitimacy and influence is fundamentally what irregular warfare is all about and, for this reason, the annex—while very welcome and important—is also insufficient for the reform and change that must now take place.

IW: Past, Present, and Future

In the annex, the Department of Defense defines irregular warfare as “a struggle among state and non-state actors to influence populations and affect legitimacy.” The term was re-discovered shortly after the 9/11 attacks and appeared prominently in the Pentagon’s 2006 Quadrennial Defense Review. Attempts to explain irregular warfare counterpose it to “traditional warfare,” which denotes militarily decisive confrontations in which victory goes to the better armed and more capable force. In irregular warfare, legitimacy, credibility, and political advantage is the prize and military efforts are only relevant insofar as they serve these goals.

The American track record with irregular warfare suffers from historically typical tendencies. The US response to 9/11 was overly militarized and concerned mostly with striking targets, so as to defeat, or at least contain, a problem with deep social and political roots. In Iraq and Afghanistan, counterinsurgency emerged as a corrective to the counterterrorist lens but in a way that mostly shaped security operations. Indeed, the lack of a truly political response, in both Iraq and Afghanistan, condemned the so-called surges in both theaters. On the whole, the American response has failed to capture the true breadth of its adversaries’ strategies, the narratives that they deploy, or their sources of legitimacy with key audiences.

With state-based use of irregular warfare becoming a major concern, similar tendencies are disturbingly clear. Against both Russia and China, the United States has traditionally relied on a military logic to sustain the status quo. The major assumption of Article 5, NATO’s collective security clause, is that the attack on a NATO member would be unambiguous and military, and that the alliance could therefore prepare and mount a swift and effective response—hence the deterrent effect that helped protect Europe during the Cold War. Similarly, the initial approach in the South China Sea was that enough carrier strike groups, or a conventional military advantage, would deter the Chinese government’s annexation of disputed territory.

Regrettably, Russia and China have both broadened their strategies to emphasize a range of nonmilitary lines of effort, used to interfere with their adversaries, destabilize target countries, and increase their own influence and reach. In failing to capture the entirety of this strategy, in failing to understand the sources of legitimacy for the counter-hegemonic narratives that Russia and China espouse, the US response has also failed to engage optimally with the realities of great power competition. For one, it has not credibly developed or sustained its own narrative, or its right to lead, which facilitates the continued salami slicing of the rules-based international order fashioned by the West in the aftermath of World War II.

American strategic malaise in both confrontations—against nonstate and state rivals alike—is forcing us to revisit the logic of irregular warfare. For one, it is clear that while IW has traditionally been thought of as a means for nonstate armed groups to counter the advantages of mighty states, the same prerogative is also shared by state-based rivals. To some, the lesson from America’s overwhelming military victory in the 1991 Gulf War was clear: “Never fight the Americans without nuclear weapons.” As others have found, adopting the “indirect and asymmetric approaches” of irregular warfare offers a far more practical alternative, allowing them “to erode their opponent’s power, influence, and will” until military consolidation becomes possible. As the IW Annex recognizes, this is now the playbook for most US state adversaries and rivals.

As practiced by these states, but also by nonstate actors, irregular warfare presents three core lines of attack. First, irregular strategies seek to exploit the economic, societal, and political vulnerabilities of target societies to weaken the adversary and gain leverage. Targeting societal pressure points can help undermine morale, create and exploit division, and provoke violent political change. Much as the Islamic State exploited the sectarian rift between Iraq’s Sunni and Shia populations to rally a popular base, so did Russia in Ukraine, where identity, language, and religion served as pressure points for Moscow to target. Similarly, China has proved adept at establishing a strategic foothold by exploiting the economic vulnerabilities of target societies. This, in effect, is how it acquired the Hambantota maritime base in Sri Lanka and how it is establishing other footholds internationally through the Belt and Road Initiative.

Second, narratives are at the center of irregular warfare: they help achieve buy-in for political projects and shroud the nature of actions taken. Lawrence Freedman noted the growing strategic salience of narratives in 2006, describing them as “designed or nurtured with the intention of structuring the responses of others to developing events.” Given the growing importance of narrative even since then, scholars like Joseph Nye and John Arquilla now claim that, in modern conflict, “Victory may sometimes depend not on whose army wins, but on whose story wins.”

Put differently, the objective is to win the narrative before winning the war. The principle is evident in social media offensives of the Islamic State but also within the “information warfare blitzkrieg” unleashed by the Russian Federation in Ukraine (and elsewhere) or the extensive Chinese use of disinformation to avoid what it calls the Tacitus trap—the danger of losing credibility with the citizenry. In all these cases, the key lies in presenting actions as going with the grain of local want, so as to make any associated gains more sustainable and difficult to undo.

Third, irregular warfare fuses and takes advantage of multiple lines of effort, compensating for weakness—typically military weakness—by bringing other efforts into play. Much as insurgency blends violence with governance, essential service delivery, mobilization, legitimation, and other nonmilitary efforts, America’s state rivals also succeed by combining the threat and use of violence with political, economic, and informational efforts. Violence gains meaning through its symbiotic relation with this broader strategy—what is being done politically, through alliances and nonviolence (also known as political warfare), and by internationalizing the struggle.

Legitimacy is a leitmotif in irregular warfare. This is a central definitional point; however, it is often lost in analysis. It must therefore be re-stated that irregular warfare is not primarily defined by an asymmetry in approaches (conventional vs. guerrilla) or actors (state vs. nonstate); rather, it is a struggle defined by its objective: “to influence populations and affect legitimacy” so as “to erode an adversary’s power, influence, and will.” It is notable here that the minimum requirement in IW is not to build legitimacy, but rather to erode it; a somewhat easier task, but also one with potentially irreversible consequences.

Neither Irregular nor Warfare

The good news is that the National Defense Strategy recognizes this adoption of IW by states. It notes, for example, that “both revisionist powers and rogue regimes are competing across all dimensions of power”; that they have “increased efforts short of armed conflict by expanding coercion to new fronts . . . deliberately blurring the lines between civil and military goals.” In another key statement, it elaborates that state rivals use “corruption, predatory economic practices, propaganda, political subversion, proxies, and the threat or use of military force to change facts on the ground.” From a diagnostic point, this verbiage is spot on.

The thing is that admiring the problem is not enough—and when it comes to action there are significant lags in America’s institutionalization and operationalization of the needed capabilities. This is exactly what the IW Annex is meant to address. However, the placement of this annex as such—as an adjunct to the main text—speaks to the problem at hand. Indeed, there is something curious about the need for the United States to “institutionalize” irregular warfare after a full twenty years of nonstop engagement in precisely such efforts, and the annex is tellingly conflicted on whether IW is already a “well-honed” “core competency” that must be sustained or an area for which the United States is “underprepared.” There is a danger here of confusing experience with expertise and of downplaying the present challenge, perhaps to achieve buy-in for reform from skeptical audiences.

These problems are amplified by the term irregular warfare itself, an imperfect nomenclature that betrays the pathologies of the system charged with response. Though this argument may seem preoccupied with semantics, in two ways the concept irregular warfare undermines the very effort its introduction is meant to fuel. In short, the problem is really not all that irregular and also far more than just warfare.

First, in saying that this type of warfare is irregular, the challenge as a whole is easily framed as an alternative, or appendix, to plain old warfare, which is implicitly upheld as more common or traditional (indeed, DoD says as much in its doctrinal recognition of just two forms of warfare: “irregular” and “traditional”). Despite facing irregular challenges far more regularly than conventional ones, the US military establishment retains a lexicon that privileges comfort zones over cold realities. Traditional warfare is certainly not irrelevant, but it is invariably a violent escalation of political and social strife. Its outcomes, if they are to be durable, can only be consolidated through the continued application of politics. As such, it is the notion of “traditional wars” that is aberrational, not the opposite. At best, it represents a flawed heuristic—one that fails to account for the purpose of war by artificially detaching its military aspect from its sociopolitical antecedents and outcomes.

At worst, this dichotomy of warfares suggests an ability to pick and choose between the two. This reading is further encouraged by the context in which IW was most recently “discovered”—amid enduring counterinsurgency campaigns and the frustrating struggles of America’s post-9/11 wars. These long-running and costly wars’ taint on anything irregular likely explains why it took such great effort to include an IW Annex within the National Defense Strategy to begin with and why its declassification was far from certain and thus delayed. Indeed, as a newly appointed secretary of defense, Mark Esper made it clear that IW was part of America’s past, not its future. Speaking with students and faculty at the US Naval War College in August 2019, he noted that while many of them had spent their “career[s] fighting irregular warfare . . . times have changed. We are now in an era of great-power competition. Our strategic competitors are Russia and China.”

In dismissing irregular warfare as contests against nonstate adversaries—and in dismissing that problem as no longer de rigueur—there is a real danger that a form of warfare increasingly used also by states becomes the new “MOOTW,” the clunky acronym used by DoD in the 1990s to group (and collectively dismiss) “military operations other than war.” This would be counterproductive, as the more the United States doubles down on its conventional overmatch, the more irregular its foes will become. The more the United States emphasizes power and deterrence based on destruction, lethality, and speed, the more its adversaries will compete in influence, narratives, and ambiguity. In these areas, the United States fares less well, even when pitted against Islamist zealots and authoritarian states.

Second, if irregular warfare is not all that irregular, it also is not really warfare—or at least its designation as such causes confusion and impedes the necessary response. Violence is not a defining feature in these contests but comes and goes depending on the balance of risk and opportunity. In recognition of this trend, the IW Annex eliminated the word “violent” from the definition of irregular warfare as found hitherto in joint doctrine. Still, in nonetheless referring to this approach as warfare, the Pentagon risks militarizing not just our expectations but also the way we respond to irregular challenges, all while alienating civilian partners who feel that warfare is best left to the Department of Defense.

A better way forward would be to speak of irregular competition, which at times escalates into irregular warfare. Both varieties of irregular behavior share the aim of building or eroding legitimacy and both use “indirect and asymmetric approaches” that are typically deeply subversive. This creation of a spectrum points to the need for a national strategy that can respond to the admixture of nonviolence with violence, of war with peace. The difficulty for the United States will lie in resourcing a broadened response, all while maintaining military buy-in as but a supporting player.

Czech author Milan Kundera writes that “metaphors are dangerous”; the same applies to irregular warfare. Beyond semantics, how and where we discuss IW reflects real-world tendencies that will determine America’s success in the global competition for power and, therefore, the future of the international order it has sought to uphold. At worst, the conceptual framing of IW produces armed forces that either neglect this dominant type of warfare or treat it as a purely military challenge, and a state and society oblivious to the threat at hand and to their crucial role in the necessary response. Indeed, it is already troubling that irregular warfare, which certainly targets entire societies, is rarely discussed outside the confines of DoD.

Lessons Learned for Irregular Warfare

The societal implications and responsibilities of irregular warfare cannot be overstated. Whereas it is (dubiously) assumed that “traditional wars” will unfold on empty battlefields, with irregular warfare there is really no way to isolate the practitioners of warfare from the society they serve or to exempt those not in uniform from playing their part. For the armed services as much as the citizens of a targeted society, the message is clear: you may not be interested in irregular warfare, but irregular warfare is interested in you.

Three requirements flow from the central characteristics of IW noted above, and they tend to feature regardless of the actor involved. First, if irregular strategies seek to exploit the economic, societal, and political vulnerabilities of target societies, it follows that those attacked must engage in effective and concerted political action and reform as a means of self-defense. Addressing the vulnerabilities that invite attack might be the ideal response, yet it is also highly ambitious—be it identity politics or socioeconomic inequality, these are not issues that can be quickly or easily resolved. Instead, an initial objective might involve fostering greater resilience, particularly within the domain under attack.

In 2016, at the Warsaw Summit, NATO leaders committed themselves to just this end, focusing on priority areas like continuity of government services, energy supplies, communication, and transport. Equally critical is what the EU calls “social and economic resilience”—or the bounce-back ability following attacks on the very fabric of society, be it through the inflammation of fault lines, attempts at radicalization, or attacks on elections and systems of governance. This calls for a social compact between state and citizen, which brings forth a delicate dilemma between finding common values and having these imposed at tremendous moral and strategic cost. Still, irregular warfare remains a deeply political and social business and, for this reason, mobilization is key.

Second, if narratives are central to irregular warfare, targeted states must amass the credibility and resonance to communicate clearly. Regrettably, these qualities also form the primary targets of adversaries’ and competitors’ information campaigns. Moreover, they are difficult to regain once lost. A helpful starting point may be to have a central institution to lead the charge. In the US case, the frequent calls to resuscitate the US Information Agency (USIA) make this point; however, they also inflate that agency’s actual effect during the Cold War. As Matt Armstrong concludes, the “United States never properly armed itself, and especially not with USIA, for the cold reality of the political warfare it was embroiled in.” The recent standing up of the Global Engagement Center within the State Department is certainly promising, yet this effort lacks sufficient funding and was for long staffed mainly with contractors and detailees from the Pentagon—a sign of the State Department’s limited capacity. Regardless, knowing how to tell the story is secondary to having a story to tell and—on this front—recent American leadership on the global stage has left something to be desired.

Third, if irregular warfare blends disparate lines of effort, these must all be interrogated and countered as doggedly as the more high-profile use of violence. It is from this requirement that we arrive at the frequent, almost clichéd, exhortation for a whole-of-government approach, as the military cannot be expected (and certainly should not be left) to counter the full breath of irregular strategies all on its own. Some even speak of a “whole of society” approach, which while correct analytically raises difficult questions as to execution. The question is whether, in confronting irregular strategies, or what some call “society-centric warfare,” we have much of a choice. Michael Howard’s forewarning, in 2006, remains apt: “This is the only war we are likely to get: it is also the only kind of peace.”

It is commendable that the proponents of irregular warfare in the Pentagon have managed, after two years, to add this annex to the NDS synopsis that was already available. One hopes that the declassification of the annex will galvanize the necessary thinking and action to improve US and Western practice of irregular warfare. And yet, as we know, hope is not a strategy. It is a touch disparaging to review the many DoD instructions and guidance documents that, in the recent past, exhorted the elevation of irregular warfare to the same level as traditional warfare. In 2014 and again in 2016, DoD mandated precisely this type of rebalancing yet, judging by the need for the IW Annex in 2020, the desired reforms did not take.

There have been promising innovations. It is noteworthy that in 2017 the US Army finally announced the creation of six permanent security force assistance brigades dedicated to advising foreign forces. This announcement, sixteen years after 9/11, signaled a “marked departure” from earlier ad hoc attempts to organize the needed capability. Again, the Global Engagement Center warrants mention, given its role in combating disinformation. Recognizing the growing relevance of “gray zone” challenges, in May 2018 the Joint Chiefs of Staff began seriously contemplating American military actions “when adversarial behavior falls below the threshold that would trigger a direct response.” Most recently, the 2020 National Defense Authorization Act presaged the creation of a principal information operations advisor to the secretary of defense, and opens up a legal framework for the US military to engage in the types of nonattributable messaging that has come to define modern information campaigns.

These are all valuable initiatives and, along with other examples, they speak to the active efforts of the small community engaged with IW. And yet, these advances are also occurring in the midst of a broader IW recoil, executed by an organization yearning to close the door on the traumas of Iraq and Afghanistan and return to the supposed comforts of conventional warfare. On the day the IW Annex was released, the Army announced it was disbanding the Asymmetric Warfare Group “as the U.S. Army transitions from counterinsurgency operations to a focus on multi-domain operations and large-scale combat operations.” The tug-of-war is ongoing and, judging by the drag, stronger advocacy is urgently needed, both within the Pentagon and especially beyond, as to the enduring nature of strategic competition and war.

Most fundamental to this type of reform, however, are not the means or concepts developed, or even the capabilities built, but rather the overall strategy adopted by the state, as informed by a clear sense of policy and purpose. The objectives of irregular warfare are influence, credibility, and legitimacy, which are seen as preconditions for power. As America reflects upon its role in the world, it is perhaps within these areas where greater investment is most urgently needed.


David H. Ucko (
@daviducko) is professor and chair of the War & Conflict Studies Department at the College of International Security Affairs, National Defense University, where he serves also as director for the Regional Defense Fellowship Program. He is an adjunct professor at Johns Hopkins University and a Senior Adjunct Fellow at the Department of War Studies, King’s College London.

This article draws in part on a previous monograph co-authored with Thomas A. Marks: Crafting Strategy for Irregular Warfare: A Framework for Analysis and Action (Washington DC: NDU Press, 2020).

The views expressed are those of the author and do not reflect the official position of the United States Military Academy, National Defense University, Department of the Army, Department of Defense, or United States government.

Image: Soldiers from the Lithuanian National Defense Volunteer Force and a US Army Special Forces soldier move into a supporting fire position during a high-value target mission at Saber Junction 20 in Hohenfels, Germany, August 15, 2020. (Credit: Sgt. Patrik Orcutt, US Army)