While the United Nations (U.N.) is typically seen as a major humanitarian actor—that is, an organization committed to alleviating human suffering and improving human welfare, it is not often thought of as a military power. But that is one of the many functions that the U.N. has adopted since its origin in 1945. For over seventy years, the U.N. Secretariat—the international bureaucracy responsible for the U.N. organization's executive and administrative functions—has conducted long-term expeditionary military operations across the globe in the form of peacekeeping and observer missions. The military wing of U.N. operations has only continued to grow in the twenty-first century. As of July 2023, 87,544 peacekeepers were deployed on active operations. And that number is lower than in the recent past, down from a height of 107,805 in April 2015.Footnote ¹ During that time, only the United States has regularly maintained more foreign-deployed forces than the U.N.

Understanding the growth of U.N. military capabilities, however, requires more than a passing comparison with the contemporary U.S. armed forces. In fact, during the 1950s–1960s, the U.N. could not conduct peacekeeping operations without the participation (and financial support) of the United States military and other national armed forces. This much is unsurprising. But, as I argue in this essay, the more interesting development is that the United States' military-humanitarian support for the U.N. resulted in the creation of a distinctly international U.N. military apparatus, grafted on top of the United States' overseas base network but administered by the Secretariat. American military support to U.N. peacekeeping missions functioned as a manifestation of American global military supremacy, but ultimately the U.N. Secretariat turned this assistance into a military system that served its own objectives.

During the Korean War, American officials dominated the U.N. military and humanitarian effort. The United Nations Command, established as a belligerent in the Korean War, was in essence an American military headquarters. American officials made the key battlefield decisions while also keeping a firm hold on humanitarian and development assistance despite the titles of ostensibly “U.N.” field-based bodies.Footnote ² This dynamic changed with the U.N.'s first two armed peacekeeping missions following the Suez and Congo crises. American military-humanitarian power undergirded the logistics behind these missions, but the United States did not exert the same degree of direct control as it had in Korea. Instead, reflecting the organization's growing assertiveness under Secretary-General Dag Hammarskjöld, the U.N. Secretariat directed day-to-day operations and the construction of a U.N.-run support system.

The foundations of this U.N. military capability were laid in response to the 1956 Suez Crisis. Amidst a Franco-British-Israeli invasion of Egypt that aimed to seize the Suez Canal, the U.N. Security Council authorized the deployment of a 6,000-soldier multinational U.N. Emergency Force (UNEF) to the Sinai Peninsula and Gaza Strip. UNEF was not labeled a humanitarian operation at the time, but like other Cold War–era peacekeeping missions, it performed many humanitarian functions such as clearing minefields and unexploded ordnance, resettling displaced civilians, and facilitating prisoner repatriation. Indeed, many of UNEF's duties in Gaza involved collaborating with other U.N. humanitarian agencies to govern the large population of refugees in the territory.Footnote ³ These tasks, and the size of the UNEF force, marked a significant increase in the U.N.'s Middle East presence and stimulated an expansion of U.N. military capabilities.

And yet, the decision to establish the peacekeeping force quickly meant that there was no way that the U.N. could deploy UNEF without logistical and materiel help. The U.S. armed forces provided much of that assistance by air. During the airlift's first three months, American aircraft delivered over 155 tons of cargo and transported Brazilian, Colombian, Indian, Indonesian, Danish, Finnish, Swedish, and Norwegian troops from their home countries to the Middle East.Footnote ⁴ Countries such as Canada and Italy assisted, too, but American aircraft flew most missions and did so on a global scale. Indeed, despite Egyptian hesitancy, the prominent Canadian administrative role in UNEF was only approved because the Canadian army used the same logistical systems as the U.S. military.Footnote ⁵

The global airlift relied on a key airbase: the shared U.S. and Italian facility at Naples, Italy, which conveniently doubled as headquarters for the U.S. Navy's Sixth Fleet (see Figure 1).Footnote ⁶ Sixth Fleet was responsible for maritime operations in the Mediterranean and had recently completed an evacuation of over 1,700 American citizens from Egypt, Israel, and Lebanon when the conflict began. The U.N. opened a coordination office to facilitate the flow of supplies and personnel from around the world to Naples, then from Naples to forward bases in Egypt. By co-locating the U.N. coordination office with the regional U.S. military headquarters, UNEF and American forces managed a complex deployment process.

Figure 1. Troops from the Colombian contingent arrive at Naples on a U.S. Air Force C-124 Globemaster II transport, November 19, 1956. U.N. Photo.

Once the initial airlift ended and the peacekeepers were established, the U.S. military's role shifted to long-term mission support. U.N. records include a host of requisition requests for American military equipment. Over the peacekeeping mission's first six months, the U.S. military provided 10,000 blankets; 5,000 sleeping bags; 6,000 trip-wire flares; 1,000 helmets; 6,000 flu shot vaccines (enough for the entire U.N. force); construction equipment for housing facilities; field manuals on topics such as riot control, civil affairs, military government, and law; and 8,000 pairs of sunglasses.Footnote ⁷ To manage these requisitions, the U.N. Secretariat and U.S. Department of Defense established a process of invoices and receipts that endured beyond the end of UNEF in 1967.

The UNEF operation had the unintended consequence of rapidly and vastly expanding the quantity and type of military materiel that the Secretariat had to track, move, store, and repair, all of which necessitated that the U.N. establish a long-term liaison and administrative presence on American bases. In 1958, the U.N. relocated most personnel and logistical functions from Naples to the nearby U.S. Army supply depot in Pisa. This facility was one of the largest in Europe with 2,000 acres of storage space. The U.N. continued using American military facilities for postal services, medical treatment, twenty-four-hour radio communications to U.N. headquarters in New York, and as a transport hub.Footnote ⁸

As the U.S. and U.N. bureaucratic relationship grew closer, a similar pattern developed on a more personal level. U.N. staff members assigned to the Naples and Pisa bases intermingled frequently with American military personnel and enjoyed many of the same perks as American service members: permission to shop at the base commissary, access to medical care, the use of recreational facilities, and subsidized fuel costs.Footnote ⁹ Reliance on the United States was so high, and the relationship apparently so close, that the U.N. Secretariat gave Admiral Arleigh Burke—the Chief of Naval Operations and highest-ranking officer in the Navy—a U.N. identity card granting him access to U.N. offices and facilities.Footnote ¹⁰

The pattern of formalized American military assistance to U.N. peacekeeping operations extended beyond the Eastern Mediterranean with the establishment of the U.N. Operation in the Congo (known by its French-language acronym, ONUC) mission in 1960.Footnote ¹¹ The deepening of formal ties between the U.S. government and U.N. Secretariat reflected how the United States's interests often aligned with those of the U.N. Secretariat when crises broke out in the global South. The Suez Crisis marked the beginning of this pattern, but it was especially apparent in the way that the Kennedy Administration viewed newly independent African states. To many in the Kennedy Administration, U.N. engagement in Africa could help prevent the spread of communism there by stabilizing precarious governments and stimulating economic development—a set of policy priorities that fit nicely with ONUC's substantial nation-building component.Footnote ¹²

Once again, American military support proved vital to sustaining ONUC, which was a significantly larger operation than UNEF. A formal U.S.–U.N. assistance agreement delineated how the United States would support U.N. operations, which largely pertained to technical assistance. The U.S. government identified an executive agent within the Department of Defense that had the authority to fulfill routine U.N. requests for maintenance and technical services, spare parts, small-scale individual or organizational equipment, and rations. “Special” requests such as personnel evacuation, air and sea transportation, and the provision of large equipment such as vehicles required approval from the State Department. On the U.N. side, coordination with the United States went through the U.N. office in Pisa, Italy, that had been established for UNEF (Figure 2).Footnote ¹³

Figure 2. At the staging area in Pisa, radio-operator Jim Bos (Netherlands) manages communications between ONUC and U.N. Headquarters, August 1, 1960. U.N. Photo/AL.

The U.S. Air Force provided much of the airlift, both for the initial deployment and long-term logistical support. Flying out of U.S. bases in western Europe, the Air Force used existing U.N. staging areas at Pisa, Naples, and, sometimes, Gaza as well as intermediate bases in Libya and Nigeria. American aircraft delivered 15,000 of the 20,000 troops deployed during ONUC's first six months. Over ONUC's three-and-a-half-year existence, the Air Force flew 2,128 sorties, carrying over 18,000 tons of cargo and ferrying a total of over 63,000 U.N. peacekeepers in and out of the country on routine troop rotations. The Navy also contributed with eight cargo vessels that delivered over 5,000 tons of supplies to Congo.Footnote ¹⁴ ONUC demonstrated the expansion of U.N. capabilities for coordinating with the United States and sustaining long-term operations.

By the early 1960s, the U.N. Secretariat's military apparatus had expanded to include three key features: the acquisition of growing equipment stocks, the establishment of a permanent system of bases and depots, and the authority to direct military peacekeeping operations. The U.N.'s equipment stocks and base network owed much to American support. Peacekeeping operations stimulated the expansion of the U.N.'s physical infrastructure that included the supply depot at Pisa, the liaison office in Naples, and regular use of the Naples airbase, as well as a communications network of eight radio transmitters in New York, Europe, the Middle East, and Asia—all administered by the U.N.'s Field Operations Service in collaboration with U.N. peacekeepers.Footnote ¹⁵ By the late 1960s, the U.N.'s Pisa office had grown into a regional logistics hub, servicing both military peacekeeping and civilian development operations.Footnote ¹⁶ At the time, it was supporting U.N. observers in Israel/Palestine and peacekeepers in Cyprus, as well as providing office equipment to the U.N. Development Program in Tunisia and Yugoslavia.Footnote ¹⁷ Although repeatedly enlarged and later relocated to a former Italian Air Force base in Brindisi, the Pisa office lives on today as the U.N. Global Services Centre Brindisi, which provides logistical and information technology support services to U.N. operations worldwide.

Despite its reliance on U.S. military support for supplies, equipment, and infrastructure, the Secretariat sought to maintain a degree of distance from American influence over operational decisions. U.N. officials were far from merely American lapdogs.Footnote ¹⁸ Unlike in the Korean War, where American policy makers and military commanders made the key decisions on military operations and humanitarian relief, UNEF and ONUC field-based officials and force commanders from various countries planned and directed day-to-day operations.Footnote ¹⁹ The United States retained influence over peacekeeping operations via logistical, financial, and political backing, but did not exercise the direct authority that it had in Korea. The U.N. Secretariat also established the position of Military Adviser, filled by a brigadier general on loan from the Indian Army, to provide the Secretary-General with ready access to military expertise.Footnote ²⁰ The fact that in-house military advice came from an officer who represented the newly independent and non-aligned government of India served as a further assertion of U.N. military autonomy from the United States. In the delicate diplomatic context of the Cold War, U.N. officials were aware of how too close an alliance with the United States would hamper their international operations and limit the leadership's diplomatic agility.

The establishment of a distinct, Secretariat-run U.N. military system is significant for both modern American and international history in several ways. For one, it shows how the symbiotic relationship between American militarism and humanitarianism, which Julia Irwin articulates in her essay in this forum, legitimized U.S. military power abroad and enabled a similarly entwined expansion of U.N. military-humanitarian power. Additionally, the U.S. military's seemingly inexhaustible ability to support U.N. operations was itself a historically specific outcome of what Elisabeth Piller calls in her essay in this forum the U.S. military's “humanitarian moment” during and immediately after World War II. This “humanitarian moment” created the political and technical conditions in which the vast surplus of American military equipment and capabilities could be used in the construction of a nascent U.N. military apparatus during the 1950s–1960s. Furthermore, on a more personalized level, the experiences of U.N. personnel living on an American base in Italy, for example, are embedded within international, American, and local histories as well as longer narratives of Western colonialism and post–World War II occupation, as Adam Seipp shows in his contribution to this forum.

Although American power reinforced the U.N. in many ways, the emergence of a U.N. military apparatus also reveals the tensions between American global military supremacy and the U.N. Secretariat's growing assertiveness as an international actor. The United States' ability to wield military power through international organizations, even if only in partial or indirect ways, meant that the United States was still embroiled in conflicts around the world even when American soldiers were not present on the ground. Accounting for such indirect American military involvement presents an opportunity to reimagine the ubiquity of military intervention during the so-called “long peace” of the Cold War, as scholars such as Paul Chamberlin have done.Footnote ²¹ Yet the U.N. Secretariat did not function simply as an extension of American empire. The Secretariat crafted American support into something that suited its own goals. The growth of U.N. military capabilities therefore reflects the co-constitutive nature of international organizations and the modern nation-state.Footnote ²² American military assistance enhanced the U.N. Secretariat's capacity to intervene militarily, but as the concept and practice of peacekeeping continued to evolve during the 1960s and 1970s, peacekeeping missions came to operate with a high degree of autonomy from American oversight.

The history of American military assistance to the U.N. underscores the need to write military operations into broader histories of both the United Nations and the United States alongside humanitarian and development efforts. This is an uncomfortable proposition. U.N. activities that purport to serve the common interests of humanity can look more sinister or coercive when viewed through a military lens and in the wider context of American global supremacy. The prevalence of peacekeepers, relief agencies, and development organizations in the Middle East, for instance, has led one group of leading scholars to call the region a “land of blue helmets”—a phrase of ambiguous emphasis that conjures both militaristic and humanitarian sentiments.Footnote ²³ Indeed, as the late-twentieth-century turn toward armed humanitarian intervention and the growing militarization of humanitarian aid in places such as Somalia, Bosnia, Haiti, Kosovo, East Timor, and, more recently, Libya, attest, contemporary trends suggest that military and humanitarian histories must be understood together.