Research Brief

Operation Allied Force in 1999 was the first offensive military operation in the history of the North Atlantic Treaty Organization (NATO). The result was a decisive victory for the allies. The operation forced the Federal Republic of Yugoslavia (FRY) to withdraw its forces from Kosovo, end the ethnic cleansing of Kosovar Albanians, permit the unconditional return of refugees, and accept an international military presence in the province. Arguably, Operation Allied Force also compromised FRY President Slobodan Milosevic's ability to maintain power and ultimately resulted in his incarceration.

Despite the successful outcome, Operation Allied Force was not without problems. The military operation was undertaken with the expectation of a quick air victory, but resulted in a 78-day bombing campaign. Until Belgrade yielded in early June, Operation Allied Force had only a marginal effect on halting the violence against Kosovar Albanians, and Serb fielded forces survived NATO's air war largely intact. Moreover, on the eve of Milosevic's capitulation, U.S. and NATO decisionmakers faced the prospect of conducting a ground invasion for which they were unprepared.

The problems of Operation Allied Force provide a rich source of lessons for future military operations, as discussed in a new RAND report, Disjointed War: Military Operations in Kosovo, 1999. The analysis gives particular emphasis to the implications of NATO's decision to conduct an air-only campaign. This choice was politically acceptable, but it also made joint and multinational planning and operations more difficult, producing a somewhat "disjointed" approach. The report makes recommendations for improving planning and coordination of similar operations in the future.

The Strategic Limitations of an Air-Only Approach

Operation Allied Force demonstrated the strategic deficiencies of not taking a joint air-land approach to military operations. Such an approach presents an adversary with a range of high-level challenges and threats that are likely to be far more compelling than anything possible through a single medium. The decision to conduct an air-only campaign represented a pragmatic recognition that NATO had not mustered the political will to commit its ground forces. Nonetheless, this decision had serious consequences.

NATO's decision essentially ceded the initiative to Milosevic, enabling him to accelerate his program of ethnic cleansing and encouraging him to believe he could outlast NATO's limited military efforts. By dispersing troops and relying on concealment and sporadic use of his air defenses, Milosevic could effectively shield his fielded forces from the brunt of NATO's air power effort. The fact that Milosevic greatly miscalculated the unifying effect of his ethnic cleansing on NATO's resolve does not diminish the fundamental point that the adversary was not presented with a robust array of interlocking military threats. A clearer understanding of the limitations of a one-dimensional operation might have dispelled the notion that the threat of bombing or a few days of air strikes would cause Milosevic to back down.

The Impact of an Air-Only Campaign on Joint Planning and Operations

NATO's failure to treat the conflict as a joint operation meant that air-land synergies were not fully exploited even within the restrictive confines of an air-only campaign. For example, no Land Component Commander was ever designated in Operation Allied Force, an absence that complicated planning. The lack of a joint targeting structure made it difficult to draw upon Army and Marine Corps expertise in planning attacks against ground forces and delayed the integration of joint targeting.

A fundamental disagreement also arose among senior leaders about how to prosecute the air war. Operation Allied Force's overall commander, General Wesley Clark, serving as both Supreme Allied Commander Europe and Commander-in-Chief, U.S. European Command, stressed the importance of attacking Yugoslav ground forces, which he considered to be the ultimate guarantor of Milosevic's power. His Air Component Commander, in contrast, judged the attack of fixed infrastructure targets as the best way to pressure Milosevic. Over time, more attacks were directed against ground force targets, but the differing philosophies remained a source of tension.

One consequence of not having a true joint operation remains speculative: poorly developed ground operations. Because ground forces were rejected early on, no serious planning for their use took place. Had Milosevic decided to weather the storm of air attacks longer than he did, this absence of joint planning most likely would have delayed an allied ground attack operation until winter or the following spring—both bad options for the allies.

Task Force Hawk: A Case of Discontinuities

The strategic and operational discontinuities of Operation Allied Force are illustrated in the experience of Task Force Hawk, an Army attack helicopter strike force that was to be used as part of the NATO air operation. The Army Apaches had been requested by General Clark as an additional means of putting pressure on Milosevic. This request was controversial among senior U.S. military officers, who were skeptical about the use of attack helicopters under the conditions encountered in Kosovo. The services were concerned about the vulnerability of Apaches to Serb low-altitude air defenses, the risk of striking internally displaced Kosovars, and the lack of lucrative targets for the Apaches to attack. The absence of a maneuver ground force working in conjunction with the Apaches added to the concerns. Although the decision was ultimately made to deploy Task Force Hawk, no approval was ever given for the force's employment.

On an operational level, the lack of prior joint air-land planning contributed to delays and uncertainties by senior commanders as to how the task force would be used. No established joint procedures existed for employing attack helicopters for deep strike in conjunction with air operations and without ground forces. Such procedures were ultimately developed, but never tested, since the helicopters were not employed.


The discontinuities seen in Operation Allied Force are not unusual; indeed, they are likely to be typical of the problems faced by the United States and its allies in future military operations. But the speed, coordination, and effectiveness of future operations can be improved. The report makes several recommendations, among them:

  • Joint and service doctrine should be refined to improve the rapid integration of fixed-wing aircraft with Army attack aviation and other deep-strike land assets in predominantly air operations. Improvements will contribute to maximizing the effectiveness of these complementary assets.
  • A Land Component Commander (LCC) should be routinely designated in joint operations against enemy land forces, whether or not sizable U.S. land forces are expected to be deployed in combat. The LCC is an essential advisor to the Joint Force Commander and can facilitate access to Army and Marine Corps targeting and planning assets and competence.
  • A joint counterland control center should be established to speed the targeting process for striking fielded forces and provide dynamic control of sensors and shooters. The current process is often too long to engage fleeting targets successfully due to cumbersome control arrangements and the tendency to transmit reconnaissance data through service channels.
  • The Army should establish a contingency analysis cell to aid the Army Chief of Staff and the CINCs in identifying and assessing land force options during crises and conflicts. This is particularly important for addressing unanticipated situations for which current plans do not exist or are inadequate.
  • The Army needs to develop more expeditionary options at force levels lower than corps or full division. Task Force Hawk exemplifies the kind of modularity the Army may need in order to be most relevant in future operations. Smaller, more responsive, and more flexible force options must be part of the Army's overall inventory.

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The research summarized in this brief was carried out in the RAND Arroyo Center.

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