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Published Airpower Journal - Winter 1998

Peacekeeping at the Speed of Sound

The Relevancy of Airpower Doctrine in Opertions other than War*

Dr. John Hillen

AS WITH MOST of its history, the United States military has recently been involved in many more operations other than war (OOTW) than wars.1 Since World War I, airpower has been, more or less, an integral part of those many operations. Indeed, earlier this year, the principal military challenge to the United States and its allies was how to respond to Yugoslavia’s heavy-handed repression in the province of Kosovo—and airpower has been the military tool of choice thus far. Multinational air exercises were conducted over Albania and Macedonia on 15 June 1998 in an effort to dissuade Yugoslav president Slobodan Milosevic from using more excessive violence on his own citizens. This attempt at coercive diplomacy through the air had to be particularly subtle, because the same signals meant to cow Milosevic were not intended to embolden Kosovar separatist groups such as the Kosovo Liberation Army. This set of signals was quite nuanced—all implicitly coercive and all meant to be received via airpower. It appears at this point that the United States is exhausting its airpower options in Kosovo before considering other types of intervention, not because of airpower’s proven track record in coercive diplomacy, but because, as Eliot Cohen has written, airpower, “like modern American courtship, offers instant gratification without commitment.”2

Be that as it may, the application of American airpower does represent a serious commitment and has been an important facet of OOTWs since they were called “small wars” by the Marine Corps.3 The question under consideration here is the relevancy of airpower doctrine to OOTW—the impact or lack thereof of one on the other. This is a wholly different question from the relevancy of airpower to OOTW, although empirical judgments made from those experiences are used throughout this article to inform the first question. In those instances (airpower in OOTW), the impact of airpower remains significant but becomes less decisive in OOTW as one moves along the spectrum of conflict away from war and towards peacetime uses of the military (figs. 1 and 2). However, to hold to this is not to agree with military theorists such as Martin van Creveld, who are dismissive about airpower in low intensity conflict or OOTW. Van Creveld fantastically maintains that “in a world where almost all wars are fought not between states, but within them, many if not most of [airpower’s] elements have become useless and obsolete.”4

It is important to note that the diminishing returns from airpower in OOTW apply to the coercive elements of airpower only—the elements addressed by much or most of airpower theory and doctrine. Other elements of American airpower, such as transportation, logistics and supply, intelligence collection, command and control (C2), reconnaissance and surveillance, and psychological operations (PSYOP) have proven decisive in many OOTWs in which the United States could not use coercive airpower. For instance, the Air Force’s 193d Special Operations Wing (PSYOP), which deployed to Haiti prior to the 1994 invasion, may have contributed more to the initial success of that operation than any other air asset. Nonetheless, for the most part, this article takes the significance of those manifestations of airpower for granted and concentrates instead on airpower doctrine as it applies to the use of force.

*This article was originally presented as a paper at the Center for Strategic and International Studies (CSIS)/VII Inc. Conference on Dueling Doctrines and the New American Way of War, held in Washington, D.C., 24–26 June 1998. Special thanks to Halley Guren of Duke University’s School of Public Policy for research assistance in the preparation of this paper.

In the main, the article finds that airpower doctrine, inasmuch as it exists as a body of doctrine for OOTW, is spare but well balanced and relevant. The problem areas for doctrine are more likely to lie in standard OOTW doctrine, which is either flawed in some way to begin with and many times ignores airpower as well.

Figure 1. The Military Spectrum of Conflict

Source: Adapted from Army Vision 2010 (Washington, D.C.: Headquarters, Department of the Army, November 1996), 5.

Figure 1. The Military Spectrum of Conflict

Airpower Doctrine

The temptation in an article such as this is to paint a rigid Douhet-redux portrait of airpower doctrine. OOTW would then be portrayed as an impossibly subtle, terrifically nuanced, and tremendously sophisticated diplomatic endeavor that the inflexible application of airpower could never affect in productive ways (e.g., Curtis LeMay solutions to the Brcko corridor problem). Select bits from airpower doctrine, especially Air Force doctrine, would be juxtaposed against the emotive complexities of certain OOTW missions as a demonstration of trying to fit a square peg into a round hole.5

In fairness to both sides and with a nod to intellectual integrity, the article does not do this. Instead, one must recognize that airpower, shared as it is by all the services, has an amorphous doctrine that is flexible and sophisticated enough to have great applicability to OOTW. Moreover, OOTWs are not such a Gordian knot of intensely deep human complexities that the application of coercive airpower in many different ways cannot make a decisive difference in OOTW. In other words, blowing something up from the air (or threatening to) can sometimes make an immense difference—even in a humanitarian relief exercise. This is a fairly rare circumstance, though, and all services (and Special Operations Command [SOCOM]), which together make up and share airpower doctrine to a certain degree, recognize that the principles of OOTW are very different from the principles of war (e.g., restraint, perseverance, and legitimacy as opposed to offensive, surprise, and mass). All services (although some not as much as others) also recognize that airpower plays a key role in OOTW. For instance, the one-hundred-page Army field manual on peace operations mentions airpower only five very brief times, and only two of those references are about the coercive application of airpower.6 Given the perceived importance of Apache helicopters to recent peace operations, I would hope that the Army is updating this doctrine.

Figure 2. Effectiveness across the Military Spectrum of Conflict

Source: Adapted from Army Vision 2010 (Washington, D.C.: Headquarters, Department of the Army, November 1996), 5.

Figure 2. Effectiveness across the Military Spectrum of Conflict


All this makes for a curious state of affairs in terms of airpower doctrine and OOTW. The military community seems generally to appreciate the fundamental impact of airpower on OOTW and vice versa. Nonetheless, appreciation is not strategic and operational understanding codified in doctrine. In the main, airpower doctrine applied to OOTW is sound but spread around the services and the joint level in bits and pieces, thereby lacking the coherency that regular OOTW doctrine has achieved. The holes in the doctrine also match in many ways the dilemmas airpower has experienced in OOTW over the past few years, but causality is tough to pin down. It would be quite a stretch to say that good doctrine formulated before Bosnia and Somalia might have precluded some of the problems discussed below. For the most part, doctrine has learned from experience as much as experience from doctrine.

Airpower in Operations
other than War

US joint doctrine specifies 16 different OOTWs:

Arms Control

Combatting Terrorism

Counterdrug Operations

Enforcement of Sanctions/Maritime Intercept Operations

Enforcing Exclusion Zones

Humanitarian Assistance

Ensuring Freedom of Navigation and Overflight

Military Support to Civil Authorities

Nation Assistance/Support to Counterinsurgency

Noncombatant Evacuation Operations

Peace Operations

Protection of Shipping

Recovery Operations

Show of Force Operations

Strikes and Raids

Support to Insurgency7

This article cannot possibly treat the airpower dimension of all these operations in detail but makes some observations on several that are the most relevant to the US military in recent years. Moreover, the article focuses on an extended discussion of peace operations—specifically, the role of airpower in peacekeeping and peace enforcement, areas that have caused much angst for the United States and its allies over the past five years.

Enforcement of Sanctions

Sanctions have been a popular foreign-policy tool for American decision makers, and it is the military’s duty to enforce them. Most recently, airpower has been used extensively to enforce sanctions in the Balkans and the Persian Gulf. Such use of airpower is usually selectively employed, in that “an air quarantine is difficult to achieve because the enforcement is an ‘all or nothing’ proposition. . . . Shooting down an aircraft may be the only way to truly enforce an air quarantine, but that action may not be morally or politically acceptable.”8 This is an example of a political intent/rules of engagement (ROE) issue discussed below. Current doctrine is weak on other strategic issues that arise in regard to this mission. These include C2 problems with partner states or organizations (unilateral sanctions are rare) and force-management/readiness problems stemming from the protracted, indecisive, and—many times—monotonous nature of this task.

Enforcing Exclusion Zones

“No-fly zones” have been another hot arrow in the diplomatic quiver in recent years. US airpower has established and enforced them in the Balkans, northern and southern Iraq, and elsewhere. Other than some multinational C2 issues involved (below), they are not a doctrinal enigma. However, in Bosnia and northern Iraq, the concept of air-exclusion zones was stretched to deny movement on the ground to certain military forces. The heavy-weapon exclusion zones established by the North Atlantic Treaty Organization (NATO) around Sarajevo and Bihac are an example, as is the virtual demilitarized zone established in 1991 north of the 36th parallel in Iraq to protect Operation Provide Comfort. The enforcement of these zones, an implicitly coercive activity, has sometimes compromised the neutrality of peacekeepers on the ground and has caused friction between passive peacekeeping on the ground and peace enforcement from the air. This is discussed in greater detail below.

Humanitarian Assistance

Suppression of enemy air defenses and other coercive airpower used in coordination with humanitarian assistance operations can be a double-edged sword—and proved so in Bosnia and Somalia. On the one hand, it can protect humanitarian assistance; on the other hand, such protection can politicize the relief aid and compromise its neutrality. A particular weakness yet to be seriously addressed by airpower doctrine is the coordination of airpower supporting humanitarian assistance with the many nongovernmental organizations (NGO)/private voluntary organizations (PVO) or other agencies (such as the United Nations High Commissioner for Refugees [UNHCR]) that will be part of the relief effort. This is also discussed below.

Show of Force Operations/Coercive Diplomacy

One should note the principal doctrinal dilemma. On the one hand, shows of force rely on implicitly coercive signals that are blunt and might not be suited for the more nuanced diplomatic strategies often needed in OOTW. On the other hand (as in the Philippines in 1989), shows of force will often communicate martial intent in a constructive way. The enduring problem is that the initiative of action remains in the hands of the belligerents— although this is no different from other OOTWs. More problematic from a cultural viewpoint is that these operations suggest an overall strategy of indecisive, graduated pressure—a much-maligned way of doing business in the Vietnam War.

Strikes and Raids

Doctrinally, these are the most straightforward of all OOTWs with respect to airpower. More than any other OOTW listed, standard airpower war-fighting doctrine applies, although a competent body of specialized doctrine exists for these types of operations.

Peace Operations

Peacekeeping, for reasons of strategic culture, was for many years an unknown science as far as the American military was concerned. Classically defined, it required impartial and passive troops working with the consent of the belligerents—all qualities for which the US military of the past 50 years was not well known. Nonetheless, its basic tenets have come to be appreciated and even put into practice by the US military in the past several years. The military has also moved forward on putting into practice and formulating a doctrine (in that order) for peace enforcement. Unlike peacekeeping, peace enforcement makes less of the need for all-out neutrality and allows for the measured use of coercive force to shape the behavior of recalcitrant belligerents. Even so, observers such as James Corum maintain that “within the context of a peace-enforcement operation, however, the US military and other air forces have often exhibited a doctrinal vacuum.”9

But the search to fill that vacuum has caused a fundamental disconnect between most of the world and the US military concerning the compatibility of these tech- niques with one another. For its part, joint and other US military doctrine maintains that peace enforcement and peacekeeping can be used simultaneously or even mixed in the same missions. Joint Pub 3-07, Joint Doctrine for Military Operations other than War, states that “noncombat MOOTW may be conducted simultaneously with combat MOOTW, such as HA [humanitarian assistance] in conjunction with PEO [peace enforcement operations].”10 The Navy War College even created a hybrid sort of operation called an “inducement operation,” in which peacekeepers use coercive force with “the lightest touch possible in the hope that the parties on the ground will, in the end, assent to the UN’s mandate.”11 Most allies, however, vigorously maintain that the use of active force by peacekeepers or air forces operating in support of their mission is a Rubicon that, once crossed, completely compromises the mission.12 This issue came up constantly in Bosnia from 1993 to 1995, with the United States alone trumpeting its role as enforcer from the air and all other allies greatly resisting the idea of NATO-UN as an air/ground, active/passive team.

This became an especially contentious issue when in the summer of 1995, US air strikes on targets in the Bosnian Serb capital of Pale precipitated the Serb shelling of Tuzla (71 civilians killed) and the taking of hundreds of UN peacekeepers as hostages. It became an article of faith at NATO that peace enforcement and peacekeeping did not mix, contrary to US doctrine. The NATO secretary-general stated, “I do not believe that we can pursue decisive peace enforcement from the air while the UN is led, deployed, and equipped for peacekeeping on the ground. If we have learned anything from this conflict, it is that we cannot mix these two missions.”13 The deputy commander of the UN peacekeepers added that “there can be no gray area, no overlap of peacekeeping with peace enforcement.”14 A similar dilemma was at work in Somalia, where resentment and misunderstanding between American forces and UN peacekeepers came to a head over the use of US airpower (helicopters and fixed wing) in an active campaign against one side in the Somali conflict.

Many countries in the UN mission in Somalia (the French and Italians in particular) felt that they and other UN peacekeepers would pay the price when the US peace-enforcement effort and heavy use of coercive airpower backfired—which it did. As Dr. Mats Berdal wrote of that mission and Bosnia, coercive force used in conjunction with peacekeeping techniques tended to obfuscate “the basic distinction between peacekeeping and enforcement action . . . and highlighted the particular risks of attempting to combine the coercive use of force with peacekeeping objectives.”15

Points of Friction

Airpower doctrine, for OOTW and otherwise, has lagged behind fast-moving developments in the US OOTW experience. As a result, it must “grow” to cover certain points of friction.

Strategic Coherency

OOTWs often lack a coherent link between military means and political ends. For instance, in the current attempt at coercive diplomacy over Kosovo, how exactly can the United States apply airpower to bring about the complex political solution desired? As John Bolton said at the CSIS/VII Inc. Conference on Dueling Doctrines in June 1998, the Air Force will have to drop “autonomy bombs instead of independence bombs” on the Kosovars.16 In other instances, US airpower is asked to assist in the fulfillment of mandates well beyond its control. This was very much the experience in Bosnia, where military commanders grew increasingly frustrated by the gap between mandated ends and the means at their disposal.17 Wartime commanders usually have the operational freedom to create the conditions under which they will succeed. OOTW commanders do not. They must operate in the environment that they are given (although the good ones can shape it somewhat). In addition, the aforementioned argument over the compatibility of peacekeeping and peace enforcement often strains strategic coherence.

Institutional Coordination

Strategic coherence becomes more difficult to achieve when different institutions in charge of various facets of an OOTW are pursuing different political agendas. Adm Leighton Smith has much to say about the coordination of political guidance between the UN and NATO. Airpower doctrine is not fully cognizant of the character, nature, and core competencies of various international organizations with whom US airpower will have an association. For instance, airpower doctrine treats US airpower in the US-led multinational task force to Somalia (1992–93) the same as independently used US airpower supporting the UN mission to Somalia (1993–94). But the wholly different political character of these organizations greatly changed the circumstances and conditions under which airpower was used, even though US air units did not see a sea change in chain of command or operating procedures at their level. These issues go well beyond the C2 difficulties discussed below. US doctrine has not fully explored the political character and military competencies of organizations such as the UN and the Organization for Security and Cooperation in Europe in airpower doctrine, as well as the role of NATO or US-led coalitions as airpower subcontractors.

Command and Control

Admiral Smith’s paper for the CSIS/VII Inc. Conference on Dueling Doctrines joined many reports in properly criticizing NATO’s and the UN’s dual-key approach to the C2 of NATO air forces operating in support of UN peacekeepers in Bosnia.18 One report euphemistically referred to the C2 system as constructed (fig. 3) as “a shambles.”19 Other OOTWs (notably Somalia) experienced similar C2 problems, some caused by institutional coordination, some by “normal” multinational C2 difficulties (such as standard control procedures and clear chains of command), and other problems experienced completely within the US military community. For instance, in Somalia the 3d Marine Air Wing found that it did not have the trained personnel or facilities to operate as the airspace control agency for the unified task force that deployed there from December 1992 to May 1993.20

Figure 3. Command Relationships in Operation Deny Flight

Source: David S. Albert and Richard Hayes, Command Relationships for Peace Operations (Washington, D.C.: National Defense University Press, 1995), 63.

Figure 3. Command Relationships in Operation Deny Flight

Other Multinational Issues

Differences in force structure, interoperability, training, doctrine, modus operandi, and strategic culture can greatly affect airpower coalitions above and beyond multinational C2 issues. Airpower doctrine should not only reflect the flexibility with which US airpower must be prepared to act in many multinational settings, but also indicate that paradigms other than complete US dominance of multinational airpower operations should be explored.

NGO/PVO and Other Agency/Player Coordination

Almost all OOTWs have as players an enormous and diffuse array of national agencies, international agencies, NGOs, and PVOs. Many of these groups are tremendously influential and sometimes are even the lead agency for tasks involving the use of US airpower. Admiral Smith has much to say about his experience with UNHCR in Bosnia in this regard.21 The operation to Somalia also uncovered similar disconnects between US airpower authorities and agencies or NGOs with whom they had to comprehensively coordinate operations (such as the International Committee of the Red Cross). This complex area, which land power works extensively through civil affairs and other specially trained units, is not well covered in airpower doctrine at all. Airpower must be prepared to accommodate lead agencies other than the military or even another US government organization. The day may soon come when a Birkenstock-wearing NGO representative is a key member of the joint force air component commander’s (JFACC) staff.

Rules of Engagement

ROE issues return to the debate over the mix of peacekeeping and peace enforcement. US doctrine, searching for a way to make the mix work, looks for some criteria of proportionality in the application of coercive airpower to peacekeeping-type operations. By definition, proportionality is relative, and standard ROEs are particularly hard to pin down in complex post-cold-war peacekeeping environments. Even the famously simple “four no’s” (no bandits, no technical vehicles with crew-served weapons, no Somali-manned checkpoints, and no visible weapons) ROE in Somalia could not be enforced from the air without considerable and daily debate over individual cases that, by necessity, often had to be solved by hours of haggling on the ground. Many observers blame the heavy-handed application of US airpower in pursuit of Somali disarmament for the several dozen UN and US deaths and other troubles that followed for the UN operation in Somalia.

Airpower doctrine is hard to pin down completely because it belongs to all services, SOCOM, and the joint level.

Relevancy, Schmelevancy

Airpower doctrine is hard to pin down completely because it belongs to all services, SOCOM, and the joint level. Spread as it is over many manuals, it does not comprehensively cover airpower employment  in OOTW. What doctrine does exist, however, is fairly sound but dated (one finds hardly a word about the role of attack helicopters) and not fully cognizant of some overriding political difficulties that profoundly affect military operations. In other words, to paraphrase Clausewitz, although OOTW and airpower have their own grammar, their logic is the logic of the politics of the various organizations undertaking OOTW. Indeed, joint doctrine for OOTW recognizes the overwhelming primacy of political factors in OOTW—much more so than in war. It is particularly important, then, that airpower doctrine reflect the political imperatives that drive OOTW and that create friction in the areas outlined in this article.


1. The Congressional Research Service estimates that the US military has been used in over 250 interventions abroad, of which only five have been declared wars. CRS Report 96-119F, “Instances of Use of United States Armed Forces Abroad, 1798–1995,” 6 February 1996, 1–25.

2. Eliot Cohen, “The Mystique of American Airpower,” Foreign Affairs, January–February 1994, 16.

3. See NAVMC 2890, Small Wars, 1940.

4. Martin van Creveld, “The Rise and Fall of Air Power,” MHQ: The Quarterly Journal of Military History 8, no. 3 (Spring 1996): 81.

5. On the one hand, in the Air Force case, very little of OOTW is addressed in the following documents: Global Engagement: A Vision for the 21st Century Air Force (Washington, D.C.: Department of the Air Force, 1997); and Air Force Doctrine Document (AFDD) 2, “Global Engagement: Aerospace Power Organization and Employment,” draft, Spring 1998. On the other hand, the limited space allowed to OOTW offers lucid and coherent doctrine and is supplemented by other doctrine, such as AFDD 2-3, Military Operations other than War, October 1996.

6. See Army Field Manual (FM) 100-23, Peace Operations, December 1994.

7. See Joint Publication (Pub) 3-07, Joint Doctrine for Military Operations other than War, April 1993, ix.

8. AFDD 2-3, p. 8.

9. James S. Corum, “Airpower and Peace Enforcement,” Airpower Journal 10, no. 4 (Winter 1996): 13.

10. Joint Pub 3-07, p. 1-6.

11. Don Daniel and Bradd Hayes, Securing Observance of UN Mandates through the Employment of Militia Forces (Newport, R.I.: US Navy War College, 1995), 6.

12. See the British field manual Wider Peacekeeping (London: Her Majesty’s Stationery Office, 1995), which wholly, totally, and completely takes the opposite doctrinal stance from Joint Pub 3-07 on this issue. Such disagreement is very unusual for close allies.

13. Secretary-General Willy Claes, NATO, statement to the North Atlantic Assembly, Washington, D.C., 18 November 1994.

14. Maj Gen J. A. MacInnis, presentation to the Application of Law of War Rules Conference, Garmisch-Partenkirchen, Germany, 5–7 December 1994.

15. Mats R. Berdal, Whither UN Peacekeeping: An Analysis of the Changing Military Requirements of UN Peacekeeping with Proposals for Its Enhancement, Adelphi Paper no. 281 (London: Brassey’s for the International Institute for Strategic Studies, 1993), 76.

16. John Bolton, presentation to the CSIS/VII Inc. Conference on Dueling Doctrines and the New American Way of War, Washington, D.C., 24–26 June 1998.

17. I address this issue in my book Blue Helmets: The Strategy of UN Military Operations (Washington, D.C.: Brassey’s, 1998), 168–71 and 211–14.

18. Adm Leighton Smith, USN, Retired, “Relevancy of Air Power in Military Operations other than War” (paper presented at the CSIS/VII Inc. Conference on Dueling Doctrines and the New American Way of War, Washington, D.C., 24–26 June 1998).

19. Hillen, Blue Helmets, 161–65.

20. Corum, 15.

21. Smith.


Dr. John Hillen (AB, Duke University; MA, King’s College, London; DPhil, Oxford University) is the Olin Fellow for National Security Studies at the Council on Foreign Relations. He is a former Army officer who served with the 2d Armored Cavalry Regiment in the Persian Gulf War. A contributing editor at National Review magazine, Dr. Hillen is the author of Blue Helmets: The Strategy of UN Military Operations and numerous articles in Foreign Affairs, Orbis, Strategic Review, Joint Force Quarterly, Parameters, and many other periodicals.


The conclusions and opinions expressed in this document are those of the author cultivated in the freedom of expression, academic environment of Air University. They do not reflect the official position of the U.S. Government, Department of Defense, the United States Air Force or the Air University.

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