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January 2016 Online Exclusive Article

The Nature of War:

Implications for the Debate on America’s Strategy Against ISIS

By Maj. Ben Weakley, U.S. Army

Article published on: 28 January 2016

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ISIS flag (Wikimedia Commons)

While the character of any war is unique to its context, Prussian theorist Carl von Clausewitz gives us three observations about the enduring nature of war that apply to the war against ISIS and anticipate the conflict’s course. First, war cannot be considered separately from the political purpose which animates its combatants. Second, war is interactive and even the weakest of opponents has the opportunity to strike back. Third, we cannot count on war to give us a final result; instead, what we can count on is a new strategic challenge to confront in place of the former one. As the debate over America’s approach to war with ISIS continues, advocates on both sides would better serve the American public to consider these points before promising quick, decisive solutions that come without cost, trade-offs, or risk. To do otherwise would be a failure to see war with ISIS for what it is, “neither mistaking it for, nor trying to turn it into, something alien to its nature.”1

“War Is Never an Isolated Act”2

Clausewitz tells us that violence is the essence of war; yet, war is not reducible to mindless violence. In practice, war’s violence is governed to more or less extent by its political purpose; war cannot be considered separately from its political context.3 Each actors’ political motives inform both the types and amount of force they are willing to commit; yet, as events in the conflict unfold, the war itself influences, shapes, or even changes the political objective. Often, initial political objectives are unrecognizable at the conclusion of a war. American military involvement in Asia during the Cold War presents evidence of the role that chance and violence can play to modify a war’s political objective, as well as the moderating influence that political objectives can exert on war’s conduct. First, consider the Korean War, where American war aims began with the destruction of the North Korean armed forces and the reunification of the peninsula under a democratic Korean government. These goals did not account for the possibility of Chinese intervention; when the introduction of Chinese troops in late 1950 caused American leaders to realize that the reunification of Korea would require taking the war into China, the U.S. moderated its war aims to the restoration of the status quo ante, a divided Korea with a free and democratic South Korean government.4 Next, consider how the desire to prevent horizontal escalation involving China restrained the American use of force in the Vietnam War. Fear of full-scale Chinese intervention, an artifact still fresh from memories of Korea, could be seen in the American military’s lack of appetite for introducing ground troops into Vietnam in support of the French throughout the 1950’s, and later in limitations to the ROLLING THUNDER aerial bombardment campaigns against North Vietnam. That American land forces were used only to defend South Vietnam and not to attack forces or seize territory in North Vietnam speaks to the political influence on the use of force.5

Like the American experience in Korea and Vietnam, the war with ISIS cannot be considered in isolation from its ultimate aims. A consideration of each side’s goals show an asymmetry in the amount of force each side is willing to bring to bear; American means are limited by geopolitical realities and the risk of escalation while ISIS’s desire for escalation is only restrained by the means it possesses.

For America, enduring national goals articulated in the 2011 National Strategy for Counterterrorism and, more recently, in the 2015 National Security Strategy set the security of the American people and their homeland as a guiding principle of national policy.6 Toward ISIS, the U.S. holds the articulated objective of destroying the group.7 One can infer that, among other American interests, the destruction of ISIS is ultimately intended to serve the security of American people; eliminate ISIS and ISIS cannot attack the U.S. As straightforward as these goals appear, the geopolitical situation imposes restraint on the U.S. America must calibrate its actions to prevent horizontal escalation into a wider war, as there is only so much it can do with force of arms if it is to avoid overt conflict with Russia or Iran. At the same time, America has other global interests to defend. Even if the U.S. makes destroying ISIS the top priority, it cannot do so at the expense of ignoring other challenges like responding to aggressive Chinese territorial claims in the South China Sea, or confronting Russia on NATO’s border.

On the other hand, ISIS’s goals seek and even require escalation, leaving the group with few restraints on the scope and scale of their violence other than the means available. If jihadist texts such as The Management of Savagery represent the group’s strategic approach, one can quickly see ISIS’s ultimate aims with regard to the U.S. and its western allies.8 ISIS’s ultimate goal is expansion of the power vacuum we currently see in Iraq and Syria, “the region of savagery” as the text calls it, so that the group can replace former apostate states by providing its version of security and services to the populace, expanding the caliphate in the process. Toward this end, ISIS seeks to provoke the U.S. into a large-scale war. By portraying this war as “America against Islam,” ISIS seeks to rally moderates and secularists to their cause, or at least separate them from alliance with western powers. ISIS seeks to demonstrate some level of success against American military power and play to regional anger over another heavy-handed American intervention in the Middle East in order to increase recruiting and bring new converts into the fold. Eventually, ISIS believes it could exhaust the U.S. and deny its attempt to assert control over the Middle East, discrediting it as a superpower and setting conditions for further expansion of the caliphate.9 Assuming this line of thought, one sees also that ISIS’s objectives are not bounded by time. If setbacks occur, the group assumes a greater will to resist will allow it to persevere; so long as the “region of savagery” increases in the end it has created its opportunity.

Even if one assumes the more apocalyptic versions of the group’s goals, the conclusion remains: ISIS sees benefit from any form of U.S. escalation, even if such escalation results in setbacks, loss of territory, or the temporary destruction of the group’s ability to administer a caliphate.10 Whether the group actually realizes the desired effects of an increased American intervention is irrelevant at this stage of analysis; it is enough to know that they desire escalation and anticipate that they will act to provoke an American response.

“War Does Not Consist of a Single Short Blow”11

Clausewitz grounds the theory of war in the relationship between violence, the guiding influence of political purpose, and chance:

These three tendencies are like three different codes of law, deep-rooted in their subject and yet variable in their relationship to one another. A theory that ignores any one of them or seeks to fix an arbitrary relationship between them would conflict with reality to such an extent that for this reason alone it would be totally useless.12

It follows from this interactive relationship that war cannot be an act of unlimited, one-sided, instantaneous violence. The implication is that war is not a one-sided act, but a series of interactions by competing actors. If war were a single decisive act, its conduct would merely be an exercise in calculating which side could bring the greater means to bear.13 But, no matter how overwhelming the force applied may be, it cannot be sustained indefinitely, nor can it be successful so long as the adversary possesses the will to resist. Simply put, war is not a one-sided activity and any analysis must account for the very real possibility that the adversary will strike back, even when overmatched and presented little reason to hope for success. One can see this phenomenon in play during the closing phases of the Second World War. Nazi Germany desperately employed V2 rockets by the thousands against civilian targets in London from September 1944 to March 1945, despite all signs that the Nazi government’s survival was increasingly unlikely. German use of these early guided rockets, initially developed as long-range artillery or air-defense weapons, was clearly insufficient to prevent the inevitable collapse of Nazi Germany; yet, as Allied victory appeared increasingly inevitable in late 1944 and early 1945, German propaganda portrayed the V2 rocket as a “wonder-weapon” that could alone change the outcome of the war.14 With this case in mind, one should remember that war’s nature tends toward retaliation and away from de-escalation, particularly when one or both sides’ existence is at stake. This appears to be all the more true as a combatant becomes increasingly desperate to secure its survival.

War’s interactive nature tells any observer that the more force America applies toward ISIS’s destruction, the harder ISIS will try to strike at American interests, including American citizens in the homeland. Turning again to The Management of Savagery, one can see the logic of retaliation and deterrence behind ISIS’s behavior. For ISIS, retaliation is a requirement to deter future attacks or provoke an escalatory overreaction by its foe, and the appropriate target is not limited by geography, time, or western notions of proportionality.15 The lesson from the 2004 Madrid Train Bombings undoubtedly validates this logic, as attack by self-radicalized terrorists inspired by Al Qaeda propaganda altered the outcome of Spanish elections and brought in a government that quickly withdrew from the American-led coalition in Iraq.16 Over ten years later, events clearly show ISIS applying this logic in practice. The likely bombing of a Russian passenger flight leaving Sharm-el-Sheik, Egypt on October 31, claimed by ISIS’s affiliate in the Sinai, is quite easily seen as the response to Russian intervention in Syria.17 Though there were many possible reasons for ISIS to attack Paris in November 2015, most suggest that the group targeted Paris in response to French participation in the U.S.-led coalition fighting ISIS.18 ISIS’s own propaganda arm confirms the logic of retaliation, describing the recent attack in Jakarta, Indonesia, when, “a group of soldiers of the caliphate in Indonesia targeted a gathering from the crusader alliance that fights the Islamic State in Jakarta.”19

Because war is interactive, there is no reason to believe ISIS will not seek retaliation by attacking the American homeland in response to any American escalation. Following the group’s demonstrated thinking and behavior, we have good reason to believe American citizens in the homeland will be increasingly targeted in response to any American escalation. While terrorist plots have targeted the American homeland persistently over the last decade and a half, global connectivity and the internet make directing, or at least inspiring, an attack easier than ever.20 Putting this threat in perspective, even though the overall likelihood of any one plot succeeding is incredibly low, “the number of successful attacks goes up with the number of attempts to incite them,” and ISIS faces few costs or barriers to using the internet and social media to inspire would-be sympathizers.21 Understanding how ISIS thinks about retaliation and acknowledging that connecting with or inspiring potential attackers is easier than ever, it follows that any approach to destroying ISIS must account for additional risk to the American people in the U.S. Homeland, some of which the nation may not be able to fully mitigate.

“In war, the result is never final”22

Third, as Clausewitz notes, the outcomes produced by war are never final; even the most decisive battlefield victory does not easily translate into lasting strategic effect or political achievement, and the termination of one conflict often produces the necessary conditions for future conflict.23 For example, the aftermath of British Victory in the Seven Years War, or French and Indian War in North America, produced the conditions for the American Revolution a mere two decades later. When Great Britain and France fought for control over their colonial possessions beyond Continental Europe, the result in North America was the 1763 French defeat at Quebec which left the British in control of virtually all of North America between the Mississippi River at the Atlantic Coast.24 The cost of war in North America and elsewhere doubled the British national debt and increased its budget by a factor of ten; the need for a standing army and fortifications to secure against lingering French, Indian, and Spanish threats in North America necessitated the taxation policies, like the Writs of Assistance and the Stamp Act, that followed the war.25 These policies were the first moves in a series of events that led to the American Revolution and the British decision to oppose it with force; paradoxically, the British squandered over £100 million to lose the American colonies over the enforcement of tax policies aimed at paying down the original French and Indian War debt.26 This case clearly demonstrates that, while war can often fail to achieve its intended outcome, even those wars seen as successes leave in their aftermath new and unanticipated strategic challenges.

War’s lack of finality remains valid in today’s fight with ISIS; American military planners and political leaders cannot count on war to produce results without unintended consequences. Two points are clear. First, the destruction of one Salafi jihadist movement rarely occurs without leading to the empowerment and rise of another Salafi jihadist movement. ISIS’s own rise from the ashes of the former Al-Qaeda in Iraq should be evidence enough toward this observation. The declaration of an ISIS governate, or wilayat, in the North Caucasus where Al Qaeda formerly held influence, further demonstrates the point. Russia’s experience suppressing ethno-nationalist insurgency in the Chechen Wars of the 1990’s, only to see the rise of violent Salafi jihadist groups in the mid-2000’s is telling enough; ISIS’s announcement of a North Caucasus wilayat demonstrates the point, as it comes after the Russian security forces’ killed of the local Al Qaeda affiliate’s leader, initiating a decline in Al Qaeda’s regional influence.27 Whether Russia incurs a greater threat from ISIS-aligned groups than the one it face from Al Qaeda, this development shows that American officials should not be surprised if some other violent organization is empowered by ISIS’s collapse. Worse, it is entirely possible that we could see other Salafi jihadist groups adopt ISIS’s methods, the battle for supremacy among them manifesting, at least in part, in a competition to demonstrate capability through attacks on U.S. targets.

The second point is that, no matter what course the conflict takes, it will not end decisively; instead we can expect a transition to a new set of difficulties without being sure if any American advantage has been gained. ISIS’s destruction does not address the broader regional questions regarding the future of Syria and Iraq as coherent states, the possibility of Kurdish autonomy, the sectarian Sunni-Shia divide, and, closely related, the struggle between Saudi Arabia and Iran for regional hegemony. Whatever the result of America’s efforts to destroy ISIS, these problems will likely remain unresolved, along with new ones that appear along the way, like greater Russian influence in the region.

Military planners and their civilian masters with this view should understand why the campaign against ISIS will likely be long and marked with as many setbacks as successes; more importantly, they must understand the need to anticipate what might come after ISIS, whether that is a partitioned Iraq and Syria, instability suitable to produce another violent jihadist group, or increased Iranian and Russian influence in the region. Without this understanding of war’s lack of finality and the context of the current conflict, planners may expect a short, decisive conflict and clear results, which is to ignore historical evidence and fail to anticipate future challenges.


America cannot escape the fact that it is at war with ISIS. Whether or not to escalate this war will undoubtedly be a subject of passionate debate in the aftermath of the next Paris or San Bernardino. Anticipating such a debate, Clausewitz reminds us that:

The first, the supreme, the most far-reaching act of judgment that the statesman and commander have to make is to establish by that test the kind of war on which they are embarking; neither mistaking it for, nor trying to turn it into, something that is alien to its nature.28

Whether advocating for or against escalation of American commitment to destroy ISIS, American leaders and their advisors must acknowledge the fundamental disparity between the existential nature of ISIS’s objectives and the limited nature of U.S. interests at stake. Decision-makers should be clear that any escalation assumes some amount of increased risk to the American Homeland and other U.S. interests; similarly, decision-makers should be clear that sustaining the status quo effort or decreasing American effort does not eliminate the threat, either. We should also be clear that escalation of American involvement serves ISIS’s objectives, even if we confirm that ISIS’s destruction is the appropriate American objective. Finally, however the U.S. proceeds, America should understand that it pursues its objective without any promise that destroying ISIS is sufficient to achieve its primary policy goal, protecting the American Homeland, or even to produce significant U.S. advantage.

These are not happy conclusions, nor do they produce a clear solution to the ISIS problem. Instead, they remind us that we should be skeptical of any approach that promises to defeat ISIS quickly without cost, risk, or unintended consequences or risk ignoring Clausewitz’s warning about using war for “something alien to its nature.” Such is the character of this war with ISIS; such is the enduring nature common to all wars.


  1. Clausewitz, Carl von, On War, trans. Michael Howard and Peter Paret, New York, Alfred A. Knopf, 1984, 100
  2. Ibid., 87
  3. Ibid.
  4. For analysis of U.S. objectives during the Korean War, see Summers, Harry, On Strategy: A Critical Analysis of the Vietnam War, Novato, CA, Presidio Press, 1982, 58-59; see also, Bond, Brian, The Pursuit of Victory: From Napoleon to Saddam Hussein, New York, Oxford University Press, 1996, 180-181; For both the impact of Chinese intervention in Korea on American public opinion and the impact of domestic politics on American objectives in Korea, see Neustadt, Richard E. and Ernest R. May, Thinking in Time: The Uses of History for Decision Makers, New York, Simon & Schuster, 1986, 37
  5. Ibid., 57-59; Tuchman, Barbara W., The March of Folly: From Troy to Vietnam, New York: Knopf, 1984, 251, 254, 322-323
  6. The 2011 National Strategy for Counterterrorism lists as its first overarching goal, to “Protect the American People, Homeland, and American Interests,” further stating that, “The most solemn responsibility of the President and the United States Government is to protect the American people, both at home and abroad. This includes eliminating threats to their physical safety…” see Obama, Barack H. National Strategy for Counterterrorism, Washington, D.C., The White House, June 2011, 8; The 2015 National Security Strategy states, “The United States government has no greater responsibility than protecting the American people”, and, while “our obligations do not end at our borders… fulfilling our responsibilities depends on a strong defense and secure homeland.” See Obama, Barack H. National Security Strategy, Washington, D.C., The White House, February 2015, 7
  7. As recently as a December 6, 2015 address to the nation in response to the San Bernardino shootings, President Obama said, “We will destroy ISIS and any other organization that tries to harm us.” See, The White House Office of the Press Secretary. “Address to the Nation by the President.” The White House. December 6, 2015. (accessed January 11, 2016).
  8. For evidence of the influence of The Management of Savagery on ISIS’s objectives and behavior, see Hassan, Hassam. “ISIS Has Reached New Depths of Depravity. But There is a Brutal Logic Behind It.” The Guardian, February 7, 2015:
  9. Naji, Abu Bakr, “The Management of Savagery,” in The Canons of Jihada: Terrorists’ Strategy for Defeating America,” 48-87, ed. by Jim Lacey, Annapolis, MD, Naval Institute Press, 2008, 51-52
  10. Graeme Wood thoroughly treats the importance of territorial control and the concept of caliphate to ISIS’s legitimacy, the apocalyptic aspects of ISIS’s goals, and the desire on the part of ISIS to see U.S. escalation in Iraq and Syria. Wood, Graeme. “What ISIS Really Wants.” The Atlantic, March 2015:
  11. Clausewitz, On War, 87-88
  12. Ibid., 101
  13. Ibid., 87-88
  14. Dornberger, Walter R. “The German V2.” Technology and Culture, Autumn 1863, vol. 4, no. 4,, (accessed December 28, 2015): 393-409
  15. Naji, “The Management of Savagery,” 65-66
  16. Jeffery, Simon, “New Spanish PM Promises Iraq Withdrawal.” The Guardian, March 15, 2004:; see also, Hamilos, Paul . “The worst Islamist attack in European history,” The Guardian, October 31, 2007:
  17. Hanna, Jason, Michael Martinez, and Jennifer Deaton. “ISIS Publishes Photo of What It Says is Bomb That Downed Russian Plane.” CNN. November 19, 2015. (accessed January 16, 2016)
  18. McCants, Will. “Why Did ISIS Attack Paris?” The Atlantic, November 16, 2015:; see also, Mohammed, Riyadh. “Why Paris Was the Target of the ISIS Massacre.” The Fiscal Times, November 16, 2015:; see also, Callimachi, Rukmini. “ISIS Claims Responsibility, Calling Paris Attacks ‘First of the Storm’.” New York Times, November 14, 2015:
  19. Dearden, Lizzie. “Jakarta Attacks: ISIS Claims Responsibility for Suicide Bombings and Shootings in Indonesian Capital.” The Independent. January 14, 2016., (accessed January 20, 2016
  20. For empirical research suggesting that the internet accelerates and lowers physical barriers to radicalization, see, Von Behr, Ines, Anaïs Reding, Charlie Edwards, and Luke Gribbon. Radicalisation in the Digital Era: The Use of the Internet in 15 Cases of Terrorism and Extremism, Research Report, Washington, D.C.: RAND, 2013,, 16-20;
  21. Kathy Gilsinan takes a more skeptical look at the effect of internet radicalization in an article published by The Atlantic, but concedes that “To the extent that incitement to terrorism is a numbers game—even if the rate of translating such efforts into attacks is small, the number of successful attacks goes up with the number of attempts to incite them—ISIS’s command of Twitter does allow it to spread a wide net. And it’s almost certainly easier today for someone who, like the San Bernardino killers, has been “radicalized for quite some time” to find supportive material and inspiration online.” See, Gilsinan, Kathy. “ISIS and the ‘Internet Radicalization’ Trope.” The Atlantic, December 8, 2015,
  22. Clausewitz, On War, 89
  23. Ibid.
  24. Tuchman, Barbara W. The March of Folly: From Troy to Vietnam. New York: Knopf, 1984, 128-129; Lynn, John A. “States In Conflict,” in The Cambridge History of Warfare, by Geoffrey Parker, 167-188, New York, Cambridge University Press, 2009, 184-185
  25. Ibid., 130-132
  26. Tuchman, The March of Folly, 228
  27. Gambhir, Harleen, “ISIS Declares Governorate in Russia’s North Caucasus Region,” Institute for the Study of War, June 23, 2015,
  28. Clausewitz, On War, 100

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