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Hans Delbrück and the 2001-2021 War in Afghanistan

Hans Delbrück and the 2001-2021 War in Afghanistan Hans Delbrück and the 2001-2021 War in Afghanistan
Pfc. Cameron Boyd, Public domain,, via Wikimedia Commons.
To cite this article: Park, Francis J.H., “Hans Delbrück and the 2001-2021 War in Afghanistan,” Military Strategy Magazine, Volume 9, Issue 3, Special Issue, ‘What Would the Greats Say About War in the 21st Century’, spring 2024, pages 48-52.

Hans Delbrück’s theories of annihilation and exhaustion represent a useful organizing framework for a look at the war in Afghanistan, which at the end of it all, was ultimately a civil war. Afghanistan had effectively been at war since 1978 with the Saur Revolution that instituted a communist government in Kabul. Those civil wars did not end until 2021 with the collapse of the Islamic Republic of Afghanistan.

The duration of the conflict, and the longevity of many of the actors who fought in the various campaigns of the civil wars, gave credence to a Taliban expression told to their Western adversaries that “you have the watches, but we have the time.” The strategies that the West and its military forces employed in Afghanistan grossly underestimated the willingness of the Taliban to endure in the face of a far superior Western military force.

A comparison of strategies in theory

While a discussion of Delbrück’s “central problem” focuses on two forms of strategy in the form of annihilation and exhaustion, it also requires an inquiry into the theory of victory and the role that military action plays in the willingness of combatants to come to a negotiated settlement. Both of the other lines of inquiry are a useful complement to Delbrück’s strategies of annihilation and exhaustion.[i]

The notion of a theory of victory addresses the transitive aspect of annihilation and exhaustion—in a nutshell, the rationale for those forms of strategy. Both Eliot Cohen and Colin Gray have used the term theory of victory, which in other forms has appeared as a “theory of action” and more recently by Frank Hoffman as a “theory of success.” Absent a normative definition, Hoffman describes it as an explicit causal logic that serves as an actionable central idea for achieving the goals of strategy.[ii] Discussion of a theory of victory was conspicuously absent in the practice of strategy until the development of the 2018 U.S. National Defense Strategy, for which Hoffman was one of the principal authors.[iii]

A corollary to a theory of victory is the coercive role that military action plays in forcing a negotiated settlement. Barring the total destruction of an adversary, its political entities, and its population as was the case in Carthage in 164 BC, the corollary to practical coercion is that the role of military action is to achieve a more advantageous negotiated settlement. Even the supposedly unconditional surrenders at the end of World War II came with significant conditions granted to the defeated powers, conditions that were ultimately policy decisions at the national level.[iv]

Delbrück described annihilation in terms of military defeat of an adversary, after which the victor imposes conditions on the defeated power. In comparison, exhaustion seeks to wear out an adversary, whereby the defeated power accepts the conditions of the victor in lieu of continuing to incur losses in a campaign where military defeat is unattainable. A key aspect where the two approaches differ is the role of battle. In Delbrück’s description, in annihilation “it is the one means that outweighs all others and draws all others into itself,” whereas in exhaustion “it is to be regarded as one means that can be chosen among several.”[v] The implication is that a militarily inferior power can defeat a superior adversary through bleeding away the will to continue fighting.

A comparison of strategies in practice

After the end of the Cold War, the United States wielded more military might than any other country in the world. The attacks on September 11, 2001, however, came from al-Qaeda, a non-state adversary, who was allowed to operate out of states that afforded salutary neglect if not safe haven. Such was the beginning of what eventually became Operation Enduring Freedom (OEF), the name for combat operations in Afghanistan and more broadly against al-Qaeda and its affiliates. The goals of the campaign started in 2001 was to capture or kill members of al-Qaeda and to overthrow the Taliban government in Kabul. The method by which this would be achieved would not be an incremental one; as Sir Michael Howard observed shortly after the attacks, “It cried for immediate and spectacular vengeance to be inflicted by America’s own armed forces.”[vi]

At the conclusion of initial military operations in 2002 that resulted in the rapid military defeat of al-Qaeda and the Taliban, fears of a subsequent attack on the United States led to an ongoing troop presence that complemented an effort to rebuild Afghanistan. In a profoundly myopic act of mirror-imaging, the United States and its coalition partners assisted in establishing the Islamic Republic of Afghanistan, a democratic government in Kabul under President Hamid Karzai, and with it a national army out of the tribal leaders and their militias that had supported the fight against the Taliban.[vii]

However, Afghanistan had never been a unitary state; it had always been a loose confederation of regions where loyalties were primarily tribal in nature far more so than to an abstract government administered from Kabul. Unfortunately, Western foreign policy was predicated on the presumption of strong national institutions, something that had never existed in Afghanistan, and the creation of which was inimical to many Afghan power brokers, from President Karzai on down who valued political loyalty far more than a meritocracy that was alien to the tribal politics that dominated Afghanistan.[viii]

However, U.S. military policy goals for Afghanistan focused overwhelmingly on counterterrorism under OEF, which was in tension with, if not actively counterproductive to the other Western powers’ governance and reconstruction work in the International Security Assistance Force (ISAF) that was initially focused on the new government in Kabul and the provinces. The fear of terrorist attacks on the United States after 9/11 made the United States unwilling to negotiate with former Taliban to reintegrate them into the Afghan transitional government.[ix] However, there was neither published strategy nor policy, and the resultant theory of victory remained the military destruction of al-Qaeda and its Taliban hosts.

Mirror imaging also led to Western policy goals, such as reforms for women’s rights and ethnic distribution at the national level, in ways that strengthened the Taliban, splintered the power base of the government in Kabul, or both. Attempts at attacking corruption in Kabul and in the provinces and districts foundered on the industrial levels of Western spending to develop the Afghan military, government, and economy, exacerbated by the lack of conditionality in the application of that spending given the need to find Afghan proxies to administer those resources. The long-standing tribal loyalties that transcended any national identity combined with the strong role of Islam in Afghan culture to catalyze the Taliban as an entity in opposition to Western, non-Islamic outsiders.

As to military action, neither the United States nor its allies were willing or able to send forces of sufficient capability or quantity to gain momentum in the first few years of the campaign. The demand for U.S. forces for Operation Iraqi Freedom (OIF) after 2003 meant that what was left for Afghanistan was an understrength divisional task force and a joint task force headquarters that called itself “the world’s most forward-deployed AARP chapter.”[x] After 2002, Secretary of Defense Donald Rumsfeld consistently opposed any increase in U.S. forces to OEF. Instead, responsibilities and force requirements were to be offloaded to ISAF, which assumed responsibilities for security operations previously under OEF from 2003 to 2006.[xi]

Many ISAF troop contributing nations had come to Afghanistan assuming operations would be peace enforcement much like the Balkans, not the high-intensity combat operations the British and Canadians faced in Helmand and Kandahar provinces. Other countries immediately invoked national caveats to prevent their forces from being sent to those areas.[xii] Those national caveats were a symptom of the lack of consensus on what ISAF’s true mission was to be—and by extension, a lack of consensus on any meaningful theory of victory. American contributions still dwarfed every other country in ISAF even after the transfer of responsibility from OEF.

In the meantime, the Taliban rebuilt after its initial tactical defeats in 2002. They attacked symbols of the government, whether at the national, provincial, district, or local level, eventually becoming a full-blown offensive in the south.[xiii] By 2006, the Taliban had become such a threat that a major named operation was required to dislodge them, and the Taliban had gained a foothold in the south and east of Afghanistan that neither ISAF nor Kabul were able to dislodge or defeat. The absence of coalition combat power meant that Taliban tactical defeats were strategically inconclusive.

While policy direction remained elusive, a military strategy started to emerge after the 2007 appointment of an American four-star general to command ISAF. Until then, military operations were reactive attempts to capitalize on local opportunities.[xiv] The U.S. framing of counterterrorism operations under OEF did not change, even though most of its resources were spent on counterinsurgency and defense institution building that became ISAF missions. What did change, especially after 2010 was the willingness of the coalition to resource the efforts to build the Afghan National Security Forces (ANSF) and devote to it the monies and expertise required to begin training. [xv] The Afghans who were to be the backbone of the ANSF were not unlike their Taliban counterparts. Unfortunately, ISAF was also trying to communicate tenets of operations and policing that were alien to most of those Afghans and required levels of literacy, let alone education, that were not the norm in the Afghan population.[xvi]

By the time the ISAF and OEF combat missions gave way in 2015 to the non-combat Resolute Support (RS) and Operation Freedom’s Sentinel (OFS) missions respectively, the strategy became that of “advise and assist” operations, which were crafted in such a way as to prevent U.S. and NATO forces from deliberately engaging in direct combat. As with the ISAF mission, the theory of victory for the United States and its coalition partners was a nationally controlled, fully capable ANSF of mixed tribal and ethnic composition that could defeat the Taliban, or at least protect the government in Kabul and its interests without the requirement for an ongoing Western troop presence. What was missing was the umbrella of coalition combat forces that had been the security guarantor of the ANSF. Afghan special operations forces benefited from enablers provided by OFS forces, but in doing so became utterly dependent on the coalition.[xvii]

In comparison, the Taliban remained a credible military threat throughout, and were able to draw into Afghan tribal and ethnic identities in ways that never materialized for the ANSF. The Taliban were able to fight harder on less resources than their ANSF counterparts. They were motivated through religious ideology and a cultural imperative to conduct jihad against the foreign invaders from the coalition and the government in Kabul.[xviii] The Taliban also had the benefit of not trying to create a Western-style professionalized volunteer military force.

The ANSF were never able to compel the Taliban to come to the negotiating table, and Afghan power brokers were inimically opposed to a strong national force beholden to an abstract democratic government in Kabul rather than to longstanding ethnic or tribal identities. The structure of the parts of the ANSF where the army, police, and border police all answered to different chains of command meant that numerical superiority was often frittered away in rivalries between competing power centers. That competition remained a basic fact of the ANSF apparatus to the end.

The Taliban strategy to exhaust the ANSF and its Western benefactors achieved considerable success after the 2015 shift to an advise and assist mission.[xix] Western domestic disinterest in the war against the Taliban, combined with the absence of any effective attacks from al-Qaeda after 2014 meant strategic exhaustion of the coalition, and increasing pressure for coalition forces to leave Afghanistan. The death knell for Kabul was the withdrawal of U.S. military forces from Afghanistan in August 2021. The disintegration of the ANSF and the government in Kabul took weeks.

Delbrück’s View

A contributor to the ineffectual Western strategy in Afghanistan was the combination of a theory of victory that did not factor in the effects of domestic politics on foreign policy and military strategy. In spite of alarming early reports from the OEF commander and the U.S. ambassador, force commitments in the first eight years of the Afghanistan campaign were insufficient to enable U.S. or ISAF forces to consolidate gains in security force assistance or governance, let alone both, and the prospect of being an army of occupation was anathema in any Western capital. By the time ISAF got serious about building the ANSF in 2010, it was already too late.[xx]

The influence of domestic politics was also apparent in President Barack Obama’s announcement of the Afghan surge forces that doubled U.S. presence in the theater of operations from 2009 to 2011. In that statement, Obama telegraphed the end of the OEF mission at the end of 2014.[xxi] Coalition initiatives such as population-centric counterinsurgency and the Afghan surge were attempts at seizing a quick win—in effect, attempts at different forms of annihilation. In the end, those initiatives were attempts to defeat the Taliban operationally, but they were beholden to a defective theory of victory that required far more time than could have worked. In effect, those operational attempts were never reconciled with the strategic goal in any meaningful manner.

The Taliban, on the other hand, enjoyed a consistency of direction that far outlasted anything the West could bring to bear. Unlike the fragmented governance of the Western coalition and its allies in Kabul, the Taliban had clear leadership from Mullah Omar or his trusted lieutenants. Moreover, the Taliban were attempting to re-establish a prewar status quo culture based on Islam, not a new government with institutions such as a national police force and reforms for women’s rights hitherto unseen in Afghanistan. Such a positive aim for the Taliban contrasted with the American negative aim of preventing another terrorist attack on the United States. At the same time, al-Qaeda and the Taliban had an ambiguous relationship that made American disengagement from Afghanistan difficult.[xxii]

As a by-product of that positive aim, the Taliban’s identity as a fundamentalist Islamic religious order, and traditional Afghan resistance to occupation, were motivations for many who joined their ranks.[xxiii] After Obama’s announcement of a withdrawal from Afghanistan in 2014, the Taliban could afford to wait before resuming the war in earnest. They were willing to endure whatever degree of punishment that the West was willing to mete, and they were far more representative of the rural Islamic order than the urban democracy that had emerged in Kabul.

Consequently, the notion of Taliban victory was effectively overdetermined. The competing demands and absence of any common threat consensus meant that a strategy of exhaustion is the only one that could’ve worked—and the West was singularly unsuited to prevail in that kind of a war. While military victory in Afghanistan was theoretically possible, prosecution of such a campaign was not an acceptable method for the West, and the Western theory of victory was never remotely sufficient to achieve the ends it sought. While the West may have achieved tactical successes that were attempts at a strategy of annihilation, the Taliban’s strategy of exhaustion paid off with the ignominious end of the Kabul government two decades after the beginning of the war.


[i] While the translation of ermattungsstrategie is often a “strategy of attrition,” I use the translation “strategy of exhaustion,” a convention also used by the U.S. Marine Corps in their Marine Corps Doctrinal Publication 1-1, Strategy. Hans Delbrück, History of the Art of War: The Dawn of Modern Warfare, trans. Walter J. Renfroe Jr., vol. 4, History of the Art of War (Lincoln: University of Nebraska Press, 1985), 293.
[ii] Frank G. Hoffman, “The Missing Element in Crafting National Strategy: A Theory of Success,” Joint Forces Quarterly 97 (2d Quarter 2020): 56–59; Paul J. Maykish, “Upstream: How Theory Shapes the Selection of Ways in Strategy” (dissertation, Maxwell Air Force Base, Ala., School of Advanced Air and Space Studies, 2016), 29–31.
[iii] I was privy to some of those discussions given the need to reconcile the upcoming 2018 National Military Strategy with the defense strategy published immediately prior.
[iv] I am indebted to Stephen Biddle for his observations on this topic in multiple discussions over the last two years.
[v] Delbrück, History of the Art of War: The Dawn of Modern Warfare, 4:293–94.
[vi] In the absence of primary sources from the Taliban, I have used Carter Malkasian’s 2021 history of the war in Afghanistan as the evidentiary basis for the arguments being made. Malkasian’s history, which involved interviews with participants (to include the Taliban) represents as close to an even-handed treatment of the war as currently exists. Carter Malkasian, The American War in Afghanistan: A History (New York: Oxford University Press, 2021), 59; Michael Howard, “What’s In A Name? How to Fight Terrorism,” Foreign Affairs, December 1, 2001,
[vii] Malkasian, The American War in Afghanistan, 90.
[viii] Malkasian, The American War in Afghanistan, 329–31.
[ix] Malkasian, The American War in Afghanistan, 86.
[x] The AARP is the acronym of an advocacy group formerly known as the American Association of Retired Persons. Christopher N. Koontz, ed., Enduring Voices: Oral Histories of the U.S. Army Experience in Afghanistan, 2003-2005 (Washington: U.S. Army Center of Military History, 2008), 47,
[xi] Sten Rynning, NATO in Afghanistan: The Liberal Disconnect (Palo Alto, CA: Stanford University Press, 2012), 101–3.
[xii] Rynning, NATO in Afghanistan, 120–23.
[xiii] Malkasian, The American War in Afghanistan, 123–24.
[xiv] “Dan McNeill, Lessons Learned Interview (Redacted),” Washington Post - The Afghanistan Papers, accessed February 14, 2024,
[xv] While the term changed to “Afghan National Defense and Security Forces” after 2014, I use the original term in the interests of simplicity.
[xvi] Martin Loicano and Craig C. Felker, No Moment of Victory: The NATO Training Mission in Afghanistan, 2009-2011 (Maxwell Air Force Base, Ala.: Air University Press, 2021), xiv–xviii.
[xvii] I observed that phenomenon indirectly as a common theme of reporting on the Afghan National Army Special Operations Forces in 2013-2014.
[xviii] Malkasian, The American War in Afghanistan, 332–40.
[xix] Malkasian, The American War in Afghanistan, 404.
[xx] Malkasian, The American War in Afghanistan, 131–32.
[xxi] President, “The New Way Forward - The President’s Address,” The White House: President Barack Obama, December 1, 2009,
[xxii] Malkasian, The American War in Afghanistan, 162, 175.
[xxiii] Malkasian, The American War in Afghanistan, 159–62.