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date: 20 November 2017

Peacekeeping as a Tool of Foreign Policy

Summary and Keywords

Peacekeeping is one of the principal activities and foreign policy tools implemented by the international community to create and “maintain international peace and security.” Peacekeeping operations have grown in size and scope since the late 1980s and have included traditional peacekeeping, multidimensional peacekeeping, and peace enforcement. Peacekeeping operations pursue far-reaching objectives ranging from humanitarian assistance and the repatriation of refugees, over the disarmament, demobilization, and reintegration of former combatants, to liberal democratic assistance policies. The proliferation and increased scope of peacekeeping operations imply greater significance of peacekeeping as a tool of foreign policy. As such, peacekeeping operations are not deployed solely according to matters of global peace and security, but the deployment of and contribution to peacekeeping operations is increasingly shaped by individual state’s foreign and security policy considerations. An increasing literature studying the supply side of peacekeeping offers a broad range of arguments for why countries contribute to peacekeeping operations referring to realism, liberalism, alliance politics, or domestic politics. Foreign and security policy goals that states try to attain by participating in peacekeeping operations include status enhancement and influence in the international system, the reduction of the threat of conflict diffusion into its own territory and of a potential influx of refugees, or the stabilization of political relations, international trade, and alliance politics. The existing literature leaves some lingering questions and methodological challenges that require further attention. Of particular importance are questions related to the politics of tool choice and the effectiveness of peacekeeping as a tool of foreign policy. Methodological challenges exist regarding data availability and collection as well as the appropriate modelling of cooperation between different organizations conducting peacekeeping operations and the interdependence of countries’ decisions regarding their choice of peacekeeping as a tool of foreign policy.

Keywords: peacekeeping, foreign policy, peace operation contributors, peace operation types, peacekeeping motivations, peacekeeping statistics


“Peacekeeping has proven to be one of the most effective tools available to the UN to assist host countries navigate the difficult path from conflict to peace.”

(United Nations, 2017a)

Peacekeeping is often considered as the international community’s primary tool for advancing peace and security. In 1948, the first modern-day peacekeeping operation was deployed by a nascent United Nations as an innovative effort to observe and monitor peace processes. Nearly 70 years later, peace operations, including peacekeeping, peacebuilding, and peace enforcement, are central to the international community’s peace and security endeavors, whose objectives range from humanitarian assistance and the repatriation of refugees, to disarmament, demobilization, and reintegration of former combatants, as well as liberal democratic assistance policies. However, peacekeeping operations are not only deployed to address crises of global peace and security; the decision to deploy and contribute to peacekeeping operations is shaped by individual state’s foreign and security policy considerations. Does the specific conflict influence the potential contributing country’s security and defense concerns? Does the conflict affect the flow of refugees or international trade? Does contribution to the peacekeeping operation advance the contributing state’s international standing? Does it advance its regional role? Peacekeeping is a tool available to governments to pursue their foreign and security policies, and it has grown in significance and comprehensiveness since the late 1980s.

The last three decades have seen a “changed and changing landscape” of international relations and security (see United Nations Secretary-General, 2015, p. 9). The features of this post-Cold War world, including a high prevalence of intrastate wars, the rise of new security actors, and the recognition of new security threats, have led countries to transform their foreign and security policy agendas to become broader and more encompassing, and to redefine their concepts of security. Elevated policy foci include terrorism and organized crime, the proliferation of weapons of mass destruction, refugees and immigration, climate change, regional conflicts, state failure, and even humanitarian catastrophes (see, e.g., European Council, 2003, 2008). Over this period, peacekeeping has evolved into a more comprehensive and frequently applied instrument of crisis management and tool of foreign policy. For this chapter, a tool of foreign policy is defined as an identifiable method through which government action is structured to pursue a state’s goals in the international arena.1 So how does peacekeeping fit into this definition? Can peacekeeping be a tool of foreign policy?

First, a foreign policy tool has common and defining features that make it identifiable and thereby distinguishable from other instruments. Peacekeeping operations, generally, refer to activities that consist of military, police, and/or civilian personnel deployed in a country torn by conflict. These personnel aim to provide security, early peacebuilding, and political support (United Nations, 2017b). Peacekeeping operations, however, encompass a broad spectrum of configurations and can vary in how they provide peace support. As delineated in the 2015 High-Level Independent Panel an Peace Operations (HIPPO) report, these configurations “range from special envoys and mediators; political missions, including peacebuilding missions; regional preventive diplomacy offices; observation missions, including both ceasefire and electoral missions; to small, technical-specialist missions such as electoral support missions; multidisciplinary operations both large and small drawing on civilian, military and police personnel to support peace process implementation, and that have included even transitional authorities with governance functions; as well as advance missions for planning” (United Nations Secretary-General, 2015, p. 20).

Second, governments need to provide tools of foreign policy. While peacekeeping is commonly associated with the United Nations, peacekeeping operations are not limited to actions taken by the United Nations. Regional organizations, security alliances, ad-hoc coalitions, or even single states also implement peacekeeping operations. None of the international, regional, or security organizations have a standing army that they can call upon for peacekeeping operations and many organizations do not have an independent peacekeeping budget. Therefore, national governments must decide whether they want to participate in peacekeeping operations and allocate their resources to this specific tool of foreign policy. This means that each government decides whether they want to (a) give their consent to a peacekeeping operation, (b) make the necessary financial contributions, and (c) deploy military, police, and/or civilian personnel.

Third, foreign policy tools also affect and structure government action, which means that the processes and interactions underlying and generated by these tools are not just temporary but are institutionalized. Peacekeeping is traditionally guided by three principles that structure government action and set peacekeeping apart as a tool for promoting international peace and security: (a) consent of the parties to the conflict to the peacekeeping operation, (b) impartiality of the mission and individual peacekeepers, and (c) nonuse of force except in cases of self-defense and defense of the mandate (United Nations, 2017c). While these three principles have been questioned and stretched in recent years, they still guide the basic rules of engagement.

Finally, tools of foreign policy are employed by states to attain their goals in the international arena. The U.S. Department of State (2003), for instance, lists “achieve peace and security,” “advance sustainable development and global interests,” “promote international understanding,” and “strengthen diplomatic and program capabilities” as its strategic objectives. Peacekeeping is one tool to realize these or parts of these broad goals, particularly international peace, and security. Furthermore, peacekeeping is a useful instrument to tackle more specific security and foreign policy concerns, such as the threat of terrorism, refugee inflows, and conflict diffusion.2

Evolution of Peacekeeping as a Tool of Foreign Policy

As of December 2016, there are 30 active peacekeeping operations with more than 190,000 personnel in the field (see Figures 1 and 2 below). More than 120 countries contribute uniformed personnel to these operations. UN peacekeeping spending reached approximately $8 billion in 2016/2017 (United Nations, 2017d). While the United Nations is the primary supplier of peacekeeping operations, a range of organizations engage in peacekeeping activities, including the North Atlantic Treaty Organization (NATO), Organization for Security and Co-operation in Europe (OSCE), African Union (AU), European Union (EU), Commonwealth of Independent States (CIS), Economic Community of West African States (ECOWAS), and the Pacific Island Forum (PIF). However, the aforementioned actors have not always been so engaged in the practice of peacekeeping, as the size, prevalence, and scope of peacekeeping have changed substantially since the late 1980s. The descriptive statistics presented in this section illustrate this proliferation of peacekeeping operations, the rise in resources supplied to these operations by individual countries, the increased scope, goals, and functions of peacekeeping operations, and specific contributor-related trends. As such, peacekeeping has increased in relevance as a tool of conflict management for the international community and as a tool of foreign policy for individual countries.

Figure 1 shows the number of UN and non-UN peacekeeping operations deployed over time. It is readily apparent that peacekeeping operations have been deployed much more widely since the end of the Cold War. Until around 1990, there were only on average about four UN peacekeeping missions and three non-UN operations deployed each year. The number of UN and non-UN missions combined only reached 11 in 1965. A great surge in UN operations began in 1988, and between 1988 and 1993 alone, the United Nations conducted more peacekeeping operations than in the previous 40 years combined. Non-UN operations followed a similar pattern, and the number of operations increased dramatically after 1992. The high point in the post-Cold War period were an impressive 39 missions in 1999 and again in 2008.

This surge in peacekeeping operations can be attributed to both a rise in demand and a rise in supply, linked to the systemic change of the post-Cold War international system (see Bellamy, Williams, & Griffins, 2010, pp. 94–97; Diehl & Balas, 2014, pp. 54–57). On the demand side, the 1990s saw a surge in the number of intrastate conflicts. This rise in ongoing conflicts required additional missions to monitor and implement ceasefires and peace accords. Furthermore, successful missions of the late 1980s and early 1990s increased confidence in the utility and effectiveness of peacekeeping operations as an instrument available to the international community and individual countries. Alongside this increased demand, peacekeeping operations were also more readily supplied in the post-Cold War period. Peacekeeping during the Cold War era was marked by superpower politics and reciprocal blockage in the UN Security Council. The superpowers used the blockage of peacekeeping as an instrument in their foreign policy toolbox. This obstruction came to an end in the late 1980s and gave way to more cooperation in the Security Council and beyond. Additionally, the new post-Cold War order, marked by an accelerated process of globalization, entailed a shift of foreign policy goals toward the promotion of a post-Westphalian conception of stable peace and humanitarian engagement. On top of that, the peace dividend of the early 1990s freed up military resources from traditional defense spending, which could then be deployed in peacekeeping operations. This increase in supply and demand enabled the rise of peacekeeping as a more frequent and potent tool of foreign policy (Bellamy, Williams, & Griffins, 2010, pp. 94–97).

Peacekeeping as a Tool of Foreign PolicyClick to view larger

Figure 1. Number of UN and non-UN peacekeeping operations, 1948–2016.7

Rising numbers in peacekeeping missions engender rising demands in resources, including financial resources, logistics, and personnel. These resources need to be supplied by individual countries to ensure that peacekeeping missions can be launched. Institutional arrangements regarding the supply of these resources differ slightly. For financial contributions to UN missions, UN members are assigned a fixed share of the financial costs of a UN peacekeeping operation, based on a special scale of assessments under an intricate formula taking into account, among other things, the relative economic wealth of a member state and whether it is one of the five permanent members of the UN Security Council (United Nations, 2017e). Most non-UN missions, on the other hand, are financed on a voluntary basis. The basic rule for those peacekeeping missions is that “costs lie where they fall”—contributing countries send their personnel and equipment, and cover the associated costs (Tardy, 2013). Personnel contributions, which include military, police, and civilian personnel, are voluntary for both UN and non-UN missions. For UN missions, though, contributing countries are compensated at a rate of more than $1,332 per peacekeeper per month (United Nations, 2017e). Hence, UN compensation can imply that some countries with low costs for their troops can even earn money by sending them to UN missions.

Figure 2 presents the yearly number of UN and non-UN peacekeepers. Until 1956, few peacekeepers—merely military observers—were deployed. This changed with the Suez Crisis and the launch of the First United Nations Emergency Force in November 1956, as well as the Organization of American States’ (OAS) Inter-American Peace Force in the Dominican Republic. Thereafter, the average number of deployed peacekeepers settled at approximately 22,000 per year until the end of the Cold War. Corresponding to the rise in peacekeeping missions, the amount of deployed peacekeeping personnel rose sharply in the 1990s, with a high point of almost 70,000 UN personnel in 1993/1994 and 150,000 non-UN personnel in 1995/1996.3 Since 2000, another surge in deployed peacekeeping forces has arisen. UN deployments reached an all-time high of 106,830 peacekeepers in 2015 and non-UN peacekeeping reached a maximum of more than 250,000 in 2004. The non-UN numbers are predominantly driven by NATO’s International Security Assistance Force (ISAF) in Afghanistan (December 2001–2014) with a size of approximately 130,000.

Apart from the personnel burden, peacekeeping operations also involve enormous financial burdens to cover personnel costs (e.g., military, police, and civilian personnel), equipment, logistics, infrastructure, communication, and medical expenses. UN peacekeeping spending rose tenfold from an annual average of $208.5 million in the 1980s to $3.5 billion in the 1990s, and increased again to $8 billion in 2016/2017 (Khanna, Sandler, & Shimizu, 1999, p. 345; United Nations, 2017e). Non-UN peacekeeping missions cost $121.591 billion for the period from 1994 to 2006 (Gaibulloev, Sandler, & Shimizu, 2009, p. 828).4 Given that all personnel contributions and non-UN financial contributions to peacekeeping operations are voluntary, these figures suggest that countries have identified an increased relevance and value of peacekeeping for their policy goals.

Peacekeeping as a Tool of Foreign PolicyClick to view larger

Figure 2. Number of troops sent, 1948–2016.8

Transformation of peacekeeping since the late 1980s was not only quantitative but also qualitative in form (United Nations Secretary-General, 1995, p. 3). Peacekeeping as a tool to manage armed conflict has continuously evolved and adapted to respond to new crises in the most effective and appropriate way possible. As a result, peacekeeping operations have become more complex, encompassing a broad spectrum of configurations and functions. They have evolved into an instrument that countries can and do apply to an ever greater scope of foreign policy goals.

The evolution of peacekeeping is often described in terms of generations, representing different types of peacekeeping operations. Scholars have differed in the number of categories they have ascribed to peacekeeping. Goulding (1993), for instance, presented five types: (a) preventive deployment, (b) traditional peacekeeping, (c) operations to implement a comprehensive settlement, (d) operations to protect the delivery of humanitarian relief supplies, and (e) deployment of a UN force in a country where the institutions of state have largely collapsed. Bellamy, Williams, and Griffin (2010) offer seven types, and Diehl, Druckman, and Wall (1998) even offer 12 types. These types highlight different functions and goals of peacekeeping. To summarize this concisely, Figure 3 classifies all UN peacekeeping operations up to 2016 into three peacekeeping types. For each year from 1948 to 2016, the proportion of traditional peacekeeping, multidimensional peacekeeping, and peace enforcement is depicted. While these types are not chronological, more complex missions have proliferated since the end of the Cold War.

Traditional peacekeeping is narrow in scope and range of activities. The focus lies on the monitoring of borders and establishment of buffer zones following ceasefire agreements with the goal to create an environment facilitating efforts of peaceful conflict resolution. The First UN Emergency Force (UNEF I), established in November 1956 and active until June 1967, was a traditional peacekeeping operation and the first of its kind. The mission was established to secure and supervise the end of the Suez Crisis, including the withdrawal of the armed forces of the United Kingdom, Israel, and France from Egypt, as well as the establishment of a buffer between Egyptian and Israeli forces. In establishing UNEF I, UN Secretary-General Dag Hammarskjold and UN General Assembly President Lester Pearson defined the three core principles of peacekeeping: (a) consent of the conflicting parties, (b) impartiality, and (c) minimum use of force (for self-defense). These principles have long been the standard of legitimacy guiding and defining (UN) peacekeeping as a tool for promoting international peace and security; they underlie traditional peacekeeping operations and guide other types of peacekeeping. However, more recent peacekeeping experiences, particularly from some peacekeeping operations in the 1990s, have shown that these principles sometimes conflict with peacekeeping demands as well as operational effectiveness. The international community has learned that, under certain conditions, actions compromising consent are necessary, it may be necessary to take sides against a party that endangers the operation, and the use of force may be required to protect the mission’s objectives or humanitarian victims (see Lipson, 2007). Multidimensional peacekeeping and particularly peace enforcement embody these realizations.

Multidimensional peacekeeping gained prominence amid the shifting international context of the late 1980s into the early 1990s. This period saw the rise in intrastate wars while, freed from its previous rivalry, the Security Council could authorize more complex missions with expanded mandates to meet the additional demands of these new wars. The missions in Cambodia (UNACMI, 1991–1992; UNTAC, 1992–1993), Bosnia (UNPROFOR, 1992–1995), and Somalia (UNOSOM I, 1992–1992) differed qualitatively from earlier operations, merging humanitarian aid and state-building programs with traditional peacekeeping tasks. The objectives of multidimensional peacekeeping operations are to promote the implementation of comprehensive peace agreements and to assist in building a sustainable peace. With this wider range of objectives, peacekeeping operations became multifunctional, including security, humanitarian, and political goals, and thus enhancing the applicability of peacekeeping as a tool of foreign policy. The tasks typically added to traditional mission mandates include humanitarian assistance; monitoring human rights; the disarmament, demobilization, and reintegration of former combatants (DDR); repatriation of refugees; liberal democratic assistance policies to facilitate, support and supervise elections, the rule of law, and legitimate and effective governance institution. The growing list of tasks was captured in the 1995 Supplement to an Agenda for Peace (United Nations Secretary-General, 1995, p. 6).

Peace enforcement refers to missions characterized by an increased license to use force and are typically authorized under Chapter VII of the UN Charter. This authorization has profound effects on the three core principles of peacekeeping; enforcement missions do not necessarily require the consent of the conflict parties and, while they try to be impartial in dealing with the involved parties, it may be necessary to use force against one or more of them to safeguard the objectives of the mission and to impose peace. Peace enforcement missions usually feature a range of responsibilities consonant with multidimensional peacekeeping operations. Notable UN peace enforcement missions include the UN Protection Force in Bosnia and Herzegovina (UNPROFOR, 1992–1995), the UN Mission in Sierra Leone (UNAMSIL, 1998–1999), and the UN Transitional Administration in East Timor (UNTAET, 1999–2002). Many peace enforcement missions, though, are not carried out by the United Nations but by regional organizations or ad hoc coalitions, especially if they are so-called “humanitarian interventions” focusing predominantly on human rights. Emblematic for these peace enforcement missions were NATO’s involvements in former Yugoslavia, particularly in Kosovo (KFOR, 1999–2017 and beyond). Another example is the Australian-led International Force for East Timor (INTERFET, 1999–2000). These missions are often temporally limited and aim to create a peaceful environment in which the United Nations can carry out civilian activities.

Peacekeeping as a Tool of Foreign PolicyClick to view larger

Figure 3. Different types of UN peacekeeping operations, 1948–2016.9

The quantitative and qualitative changes of peacekeeping were accompanied by shifts in the composition of the main contributing countries. Again, in most instances, countries can decide whether and how much they want to contribute to peacekeeping operations; particularly personnel contributions are voluntary across all organizations conducting peacekeeping missions. Countries can hence strategically instrumentalize peacekeeping contributions as a tool to advance their security and foreign policy goals. Shifts in patterns of peacekeeping engagement offer valuable insights into the motivations for peacekeeping contributions and changing foreign policy priorities. Table 1 presents these shifts among the largest personnel contributors, including military, police, and civilian personnel, to UN peacekeeping missions from 1990 to 2016.5

During the Cold War period, peacekeeping operations were dominated by Western middle powers, such as Australia, Canada, Norway, and Sweden. While the superpowers of this period disengaged from peacekeeping efforts to keep their tensions and interests out of the “impartial” peacekeeping operations, middle powers hoped that by participating, they received special recognition for their engagement and thereby enhanced their standing in the international system (see Cooper, 1997; Maloney, 2001). This arrangement continued until the early 1990s, as can be seen in Table 1. In 1990 and 1991, Canada, Finland, Norway, and Austria were among the three largest contributors. The end of the Cold War also enabled the permanent members of the UN Security Council to send personnel to peacekeeping operations, as done by France, the United Kingdom, and the United States in 1992–1995. France’s high ranking in 1992/1993 was driven by their contribution of up to 5,700 troops to the UN Protection Force (UNPROFOR) in Croatia; and the U.S. top position in 1995 was driven by their contribution of 2,226 troops to the UN Mission in Haiti (UNMIH). Since then, non-Western states have become the main personnel contributors to UN peacekeeping missions. The list of prominent non-Western donors include not only Pakistan, Bangladesh, and India but also Nigeria in the early 2000s, and later Ethiopia. From 2000 to 2014 Pakistan, Bangladesh, and India remained the top three contributors of UN personnel. Pakistan contributed around 4,000 troops to the UN Mission in Sierra Leone (UNAMSIL, 1999–2006), thereafter around 3,500 each to the UN Mission in Liberia (UNMIL, 2003–2016) and the UN Mission in the Democratic Republic of Congo (MONUC, 1999–2010), later known as the United Nations Organization Stabilization Mission in the Democratic Republic of Congo (MONUSCO, 2011–2017 and beyond). Similarly, Bangladesh focused its contribution on UNAMSIL, UNMIL, and the UN Operation in Côte d’Ivoire (UNOCI, 2004–2017 and beyond); and India on the UN Mission in Ethiopia and Eritrea (UNMEE, 2000–2008), MONUC/MONUSCO, and the UN Mission in Sudan (UNMIS, 2005–2011), whose equipment and personnel was then transferred to UN Mission in South Sudan (UNMISS, 2011–2017 and beyond). The rising peacekeeping contributions of these non-Western countries are often explained by referring to the positional or status gains expected from participation in such activities (see Krishnasamy, 2001; Kammler, 1997). Another line of argument suggests that particularly developing states such as Bangladesh contribute to UN peacekeeping to receive the financial compensation provided by the United Nations and may actually generate profit by providing peacekeepers (see Victor, 2010; Lebovic, 2010).

Table 1. Largest troop contributors to UN peacekeeping operations, 1990–201612

Year (as of December)

1. Largest (Total) Contributor

2. Largest (Total) Contributor

3. Largest (Total) Contributor


Canada (1,002)

Finland (992)

Austria (967)


Finland (1,006)

Norway (973)

Austria (967)


France (6,502)

United Kingdom (3,819)

Canada (3,285)


France (6,370)

India (5,902)

Pakistan (5,089)


Pakistan (9,110)

France (5,149)

Bangladesh (4,271)


United States (2,851)

India (2,078)

Bangladesh (2,029)


Pakistan (1,712)

Zimbabwe (1,445)

India (1,211)


Poland (1,084)

Bangladesh (1,025)

Austria (831)


Poland (1,053)

India (927)

Bangladesh (889)


India (1,898)

Ghana (1,711)

Nigeria (1,606)


Nigeria (3,525)

Bangladesh (3,258)

India (2,738)


Bangladesh (6,010)

Pakistan (5,552)

Nigeria (3,468)


Pakistan (4,677)

Bangladesh (4,211)

Nigeria (3,277)


Pakistan (6,248)

Bangladesh (4,730)

Nigeria (3,361)


Pakistan (8,140)

Bangladesh (8,024)

India (3,912)


Bangladesh (9,529)

Pakistan (8,999)

India (7,284)


Pakistan (9,867)

Bangladesh (9,681)

India (9,483)


Pakistan (10,610)

Bangladesh (9,856)

India (9,357)


Pakistan (11,135)

Bangladesh (9,567)

India (8,693)


Pakistan (10,764)

Bangladesh (10,427)

India (8,756)


Pakistan (10,652)

Bangladesh (10,402)

India (8,691)


Bangladesh (10,394)

Pakistan (9,416)

India (8,115)


Pakistan (8,967)

Bangladesh (8,828)

India (7,839)


Pakistan (8,266)

Bangladesh (7,918)

India (7,849)


Bangladesh (9,400)

India (8,138)

Pakistan (7,936)


Bangladesh (8,496)

Ethiopia (8,296)

India (7,798)


Ethiopia (8,295)

India (7,710)

Pakistan (7,156)

Participating countries do not contribute evenly across peacekeeping missions. In principle, and if peacekeeping were independent from contributor-specific interests or foreign policy goals, one would expect an even contribution of peacekeeping resources to all regions of the world. Contributors, however, appear to have greater interest in certain regions than others, depending on their foreign policy priorities. Figure 4 shows Europe’s share of personnel contributions to UN peacekeeping operations grouped by the regions receiving the peacekeeping mission. Here, two interesting observations can be made. First, in line with the discussion of Table 1, Europe’s total share in peacekeeping has been in decline since 1990. While Europe provided more than 60% of all peacekeepers in 1990 and 1991, its share was only between 6% and 7% in the 2010s. Second, Europe continuously over- and undercontributes to certain regions. For instance, Europe’s share of contributions to peacekeeping operations on the African continent always lies below its worldwide average, providing between 40% (1991) and 1% (2010–2012) of all peacekeepers in Africa. This proportion stands in contrast to its high contributions to missions in the Middle East (between 65% in 1990 and 35% in 2015–2016) as well as missions in Europe (between 40% in 2002–2004 and 93% in 2016).6 Most notable among European contributions to peacekeeping operations in the Middle East are those to the UN Interim Force in Lebanon (UNFIL), the UN Peacekeeping Force in Cyprus (UNFICYP), and the UN Disengagement Observation Force (UNDOF) in the Golan Heights. All of these missions are located in or around the Mediterranean Sea—the European neighborhood—which suggests that European participation in peacekeeping operations is driven by the conflict’s proximity to their own territory. This observation is in line with the Global Strategy for the European Union's Foreign and Security Policy and the European Neighborhood Policy (ENP), through which EU member states work with their Southern and Eastern neighbors to promote security, stabilization, and prosperity.

Similar observations of uneven distributions of peacekeepers can be seen in Asia’s share of contributions to UN peacekeeping operations (Figure 5). In this case, Asia undersupplies missions in the Middle East but usually oversupplies missions in Asia and Africa, compared to its worldwide share. The relative contribution to peacekeeping operations located in Asia is exceptionally volatile, which can be attributed to fluctuating absolute numbers of missions and peacekeepers deployed in the region. The years in which Asia’s share of contributions to peacekeeping operations within its own region dips below its worldwide average tend to be those years with a low overall number of missions and peacekeepers. For instance, only around 60 observers and civilian personnel were deployed in Asia, specifically Afghanistan (UNAMA) and Pakistan (UNMOGIP), between 2012 and 2016; and only 44 observers were deployed there in 1993, also in Pakistan (UNMOGIP). Asia’s high level of engagement in peacekeeping operations located in Africa can be attributed to Pakistan, India, and Bangladesh—the three major contributors to UN peacekeeping operations discussed previously.

Peacekeeping as a Tool of Foreign PolicyClick to view larger

Figure 4. Europe’s share of contributions to UN peacekeeping operations, 1990–2016.10

Peacekeeping as a Tool of Foreign PolicyClick to view larger

Figure 5. Asia’s share of contributions to UN peacekeeping operations, 1990–2016.11

Foreign Policy Motivations for Peacekeeping Contributions

The previous section showed that the usage, relevance, and scope of peacekeeping have increased greatly since the late 1980s. The international community in general and individual countries specifically have instrumentalized peacekeeping as a tool that can address threats and conflicts in a changed and changing security landscape. To further understand this tool, the motivations for countries to engage in peacekeeping must be considered. As the discussion shows, these motivations are typically part of a country’s foreign policy agenda.

An increasing literature studying the supply side of peacekeeping has developed in recent years. These contributions offer a broad range of arguments for why countries contribute to peacekeeping operations, referencing themes connected to realism, liberalism, alliance politics, or domestic politics. In this context, the predominant question is what type of goods or set of benefits states can obtain for participating in peacekeeping. Peacekeeping can resemble a public good, a private good, or a combination of both—so-called joint products. A public good is a good or benefit that is nonrival among nations and nonexcludable to noncontributors and, thus, available to everybody, regardless of whether they have shared the cost of providing it. A private good, on the other hand, is rival and excludable and is only available to those who have born the costs (see Samuelson, 1954; Olson, 1965). From the perspective of the public good model, peacekeeping efforts to increase international peace and security benefit all countries. The end of a conflict and increased stability not only favor the contributors to the peacekeeping mission but also promote the security of noncontributing countries. Characterizing peacekeeping as public good has profound implications because it implies that the provision of peacekeeping is inevitably affected by the collective action problem, which is related to the property of nonexcludability (Olson, 1965). This not only leads to free riding but also can result in chronic or persistent undersupply of peacekeeping missions and peacekeepers. This line of argument and the focus on the public nature of peacekeeping is prominently pursued by Sanders and colleagues (e.g., Khanna, Sandler, & Shimizu, 1998; Khanna, Sandler, & Shimizu, 1999; Shimizu & Sandler, 2002; Gaibulloev, Sandler, & Shimizu, 2009; Gaibulloev, George, Sandler, & Shimizu, 2015). Yet, the public nature of peacekeeping’s ultimate aim of international peace and security does not keep countries from prioritizing this objective among their foreign policy goals. India, as seen in Table 1, is one of the main contributors to UN peacekeeping; this country even lists the “[p]romotion of international peace and security” among its core principles of state policy according to its 1949 Constitution. Article 51 reads that “[t]he State shall endeavour to (a) promote international peace and security; (b) maintain just and honourable relations between nations; (c) foster respect for international law and treaty obligations in the dealings of organised peoples with one another; and (d) encourage settlement of international disputes by arbitration.”

Many other scholars engaging in this field of study demonstrate that peacekeeping activities not only yield public but also private benefits. The private good model highlights rivalrous and excludable country-specific benefits that motivate countries to contribute to peacekeeping operations and use them to achieve their foreign and security policy goals. Realist accounts focus on national self-interest to explain contributions to peacekeeping. As Findlay (1996, p. 8) put it: states participate in peacekeeping operations because it is “decidedly in their national security interests.” One of these national security and foreign policy goals is greater or wider influence in shaping the international system. So-called middle powers are said to have an interest in the continuation of the international status quo and choose to dominate UN peacekeeping, which they consider an established tool of the international community (Neack, 1995). Examples include Canada, Sweden, or Australia during the Cold War period, and India or Pakistan who have dominated UN peacekeeping more recently. Another widespread perception is that peacekeeping is a positional or status good. Participation in peacekeeping enhances a country’s prestige and standing in the international community, which it can then use to foster some of its foreign policy goals. It is argued that India, for instance, tries to strengthen its international status and power base by contributing to peacekeeping, hoping to get closer to its goal of becoming a “great” power and eventually obtaining a permanent seat in the UN Security Council (Krishnasamy, 2001, 2003a). Another example is Pakistan, whose peacekeeping participation is associated with its goal to strengthen its international image, reduce its isolation, and become more attractive to the international community—including the international economic and development funding that comes with it (Krishnasamy, 2001). Similarly, Bangladesh hopes to attract foreign aid and international support for its economy (Krishnasamy, 2003b). Because a peacekeeping operation is located in a certain region, private, contributor-specific benefits are often present for countries nearby or with special interest in it. Countries located nearest the conflict region face the highest threat of conflict diffusion and may experience a decrease of their own security and stability. The European Union, for instance, follows the foreign policy goal of fostering stability, security, and prosperity in its neighborhood. The peacekeeping operations in the Balkans in the 1990s and early 2000s—first conducted via NATO, later through the European Union with EUFOR Concordia in the Republic of Macedonia and EUFOR Althea in Bosnia and Herzegovina—are examples for how European countries tried to stabilize their own neighborhood and periphery. The EU has adopted their European Neighborhood Policy as a foreign policy instrument to bring Europe and its neighbors closer together and increase stability in the region. Another factor related to conflict proximity is an influx in refugees, which is often linked with negative economic and social effects (see Uzonyi, 2015). U.S. President Bill Clinton, for instance, invoked the need to stop refugee flows when he explained his decision to engage in peacekeeping in Haiti in 1994: “[. . .] [W]hen brutality occurs close to our shores, it affects our national interests. [. . .] Thousands of Haitians have already fled toward the United States, risking their lives to escape the reign of terror. As long as Cedras rules, Haitians will continue to seek sanctuary in our Nation. [. . .] The American people have already expended almost $200 million to support them [. . .] [a]nd the prospect of millions and millions more being spent every month for an indefinite period of time loom ahead unless we act.” Further foreign policy goals mentioned in the literature in relation to peacekeeping operations include economic considerations, such as trade interests, the protection of foreign direct investment, and the elimination of economic disruptions (Gaibulloev, Sandler, & Shimizu, 2009); or alliance considerations, such as the alliance security dilemma with the related fears of abandonment and entrapment (Snyder, 1984; Bennett, Lepgold, & Unger, 1994), or the finding that countries prefer to deploy troops alongside allies with similar foreign policy preferences (Ward & Dorussen, 2016). Regarding the latter, countries hope to cooperate with well trained, disciplined troops, to promote common norms, and to facilitate domestic support if allies join in (Ward & Dorussen, 2016, p. 393). To provide an overview, Table 2 summarizes these and other relevant foreign policy-related motives for contributions to peacekeeping operations.

Table 2. Foreign policy-related motives for contributions to peacekeeping operations as presented in the scholarly literature

Foreign policy-related rationales


Maintain international peace and security

  • Gaibulloev, George, Sandler, and Shimizu (2015)

  • Gaibulloev, Sandler, and Shimizu (2009)

  • Khanna, Sandler, and Shimizu (1998)

  • Khanna, Sandler, and Shimizu (1999)

  • Shimizu and Sandler (2002)

Export democratic and humanitarian principles

Influence the order of the international system

Enhance prestige, position, and power base in the international system

Threat of conflict diffusion to own territory

  • Auerswald (2004)

  • Baltrusaitis (2008)

  • Bennett, Lepgold, and Unger (1994)

  • Bennett, Lepgold, and Unger (1996)

  • Bove and Elia (2011)

  • Gaibulloev, Sandler, and Shimizu (2009)

Refugee flows from conflict to own territory

Trade with conflict region

  • Gaibulloev, Sandler, and Shimizu (2009)

Foreign direct investment in conflict region

  • Gaibulloev, Sandler, and Shimizu (2009)

Alliance considerations

  • Baltrusaitis (2008)

  • Bennett, Lepgold, and Unger (1994)

  • Bennett, Lepgold, and Unger (1996)

  • Ward and Dorussen (2016)

Military considerations (i.e., internally versus externally oriented security doctrines; occupation and training of military forces; allocation of resources)

Conclusion and Open Questions

In this chapter, peacekeeping has been presented as a tool available to governments to pursue their foreign and security policies. Peacekeeping has grown in significance and comprehensiveness since the late 1980s. Empirical trends suggest that the proliferation and increased scope of peacekeeping imply greater significance of peacekeeping operations as a tool of foreign policy. Moreover, changes in the composition of contributing countries could suggest that countries seem to follow their own foreign policy goals and that their polices can shift over time. The previous section reviewed foreign policy motivations for peacekeeping contributions. The scholarly literature identified public and private goods as explanations for countries’ contributions to peacekeeping operations, and particularly private goods are linked to specific foreign policy goals. The existing literature leaves some lingering questions requiring further attention. This chapter concludes by elaborating three substantive research areas in need of academic exploration and by highlighting three methodological challenges that researchers need to investigate further.

The first research area concerns the question of tool choice: Why do countries opt for peacekeeping as a foreign policy tool instead of alternative options? As Peters (2002) argues, the selection of policy tools is inherently political: “political factors and political mobilization affect the initial selection of instruments and the ultimate implementation of policy” (p. 552). Relevant factors influencing tool choice are individual or collective interests, ideas or ideologies, individual actors, institutions, and the international environment (Peters, 2002, pp. 553–559). These factors and the mechanisms through which policy tools, including peacekeeping, are selected differ from country to country, which complicates comprehensive research. However, it is crucial to get a better understanding of these processes to coordinate peacekeeping contributions between countries. Conflict literature on the role of leadership versus institutional limitations (e.g., Chiozza & Goemans, 2011; Horowitz, Stam, & Ellis, 2015), or the role of domestic audience costs (e.g., De Meqsuita, Smith, Siverson, & Morrow, 2005; Weeks, 2014) can provide important insights for this avenue of research.

Second, related to the politics of tool choice is the topic of instrument evaluation. Instrument evaluation usually includes the examination of effectiveness and efficiency, inter alia. Effectiveness measures the degree of success in achieving intended objectives, while efficiency assess the results in relation to the costs. Is peacekeeping an effective and efficient tool? To answer this question, the twofold effect of peacekeeping must be considered: it impacts the conflict dynamics within the receiving country or region and, at the same time, the foreign policy considerations of the contributing country. Some existing studies deal with the former effect and assess whether peacekeeping is effective according to its own goals, for instance whether peacekeeping actually creates lasting peace (see Fortna, 2004) or whether it successfully stops belligerent parties and protects civilians (see Di Salvatore & Ruggeri, 2017). The effectiveness of peacekeeping according to the achievement of a country’s foreign policy goals, however, is understudied. Has a country gained more status or legitimacy through the deployment of peacekeepers? Were the national interests protected thanks to the engagement in a peace operation?

Third, even if the questions of why peacekeeping is chosen as a foreign policy tool and whether it is an effective one are answered, it remains to be understood whether and, if so, why, peacekeeping as tool of foreign policy has changed over time. The scope of peacekeeping has increased with the evolution from traditional peacekeeping operations over multidimensional operations to peace enforcement. Is this change due to learning processes regarding foreign policy tool selection and implementation (see Levy, 1994)? Where did the learning take place? At the international level within international or regional organizations? Or within the countries contributing to peacekeeping operations and their internal bureaucracies and national leaders?

However, scholars willing to pursue the above questions and, at large, the study of peacekeeping as tool of foreign policy, should be aware of at least three empirical challenges. The first is asymmetric data information about peacekeeping operations. Available data about UN peacekeeping operations are considerably more comprehensive than data about non-UN peacekeeping operations. They cover several different peacekeeping statistics, including mission-level and contributor-level data, monthly figures, gender-disaggregated data, and fatalities (see Clayton et al., 2017). Non-UN missions, on the other hand, often lack all this information, mostly only providing yearly statistics on the size of the mission. Hence, more orderly and collective coordination is needed for systematic data collection on peacekeeping from non-UN organizations. These data are crucial because non-UN peacekeeping has become more significant over time. With this development, countries can also choose between different possible organizational frameworks for their peacekeeping involvement, which adds another dimension to their foreign policy decision making. Related to the increased and increasing involvement of non-UN organizations is the second challenge: how to empirically disentangle cooperation, collaboration and overlapping of UN and non-UN peacekeeping operations. It would be misleading to treat UN versus non-UN operations as mere alternatives. In many cases, the sequencing or simultaneous presence of different organizations occurs, for instance in Kosovo with NATO’s Kosovo Force, the UN Interim Administration Mission in Kosovo, and the OSCE Mission in Kosovo. Similarly, the Central African Republic hosted the African Union’s International Support Mission to the Central African Republic (MISCA), France’s Operation Sangaris, a European Union Force (EUFOR RCA), and the UN Multidimensional Integrated Stabilization Mission in the Central African Republic (MINUSCA) between 2013 and 2017. The academic literature defined several different forms of cooperation between the United Nations and regional organizations, such as the sequential, parallel, and integrated deployment of troops (see Brosig, 2010), but it is unclear how this affects the foreign-policy decision making and the effectiveness of peacekeeping as a tool of foreign policy. Finally, foreign policy and its related tools tend to be studied either monadically—does adopting a certain policy affect a country?—or dyadically—does the foreign policy of country A versus B affect their relationship? However, it seems that the decision to deploy soldiers in a peacekeeping operation and the level of a country’s commitment can be interdependent to the decisions, and therefore the foreign policies, of other countries. Future research on peacekeeping as tool of foreign policy will have to embrace advanced research methods such as network analysis (e.g., Ward & Dorussen, 2016) or spatial econometric models (e.g., Beck, Gleditsch, & Beardsley, 2006) to tackle these empirical and theoretical challenges.


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(1.) This definition and the following discussion are based on Lester Salamon’s definition of tools of public action (2002, pp. 19–20).

(2.) Some studies have empirically shown how the deployments of peacekeeping operations tend to limit transitional diffusion of conflict (Beardsley, 2011; Beardsley & Gleditsch, 2015). However, systematic studies on the effects of peacekeeping operations on terrorism and refugee flows are lacking.

(7.) Source: UN peacekeeping operations: United Nations (2017f); Non-UN peacekeeping operations: based on Bellamy and Williams (2015), and Williams (2016). Non-UN peacekeeping operations include regional organizations, security alliances, ad hoc coalitions, and individual states.

(3.) The surge in UN peacekeepers was caused by the operations in Cambodia, the former Yugoslavia, and Somalia, while the rise in non-UN peacekeepers can be traced back to NATO’s Implementation and Stabilization Forces (IFOR, 1995–1996; SFOR, 1996–2004) in Bosnia and Herzegovina.

(4.) This number includes the Stabilization Force in Bosnia and Herzegovina, the Kosovo Force in Kosovo, the International Security Assistance Force in Afghanistan, and the Multinational Force in Iraq.

(8.) Source: UN peacekeeping operations: Global Policy Forum (2017) and United Nations (2017g); Non-UN peacekeeping operations: based on Bellamy and Williams (2015), and Williams (2016). An important caveat here is that non-UN data is not as comprehensive as UN data: no within-mission variation is recorded and data for some early non-UN missions are missing.

(9.) Source: Authors’ own coding (based on mission statements).

(5.) The focus on UN data is due to limited data availability for non-UN missions.

(12.) Source: International Peace Institute (2017); calculations done by authors.

(6.) Europe hosted no peacekeeping operations in 1990–1991; a great deployment of troops (up to about 40,000) occurred with the United Nations Protection Force (UNPROFOR) in Croatia during the Yugoslav Wars from February 1992 to March 1995; and since 2009 only around 15 peacekeepers are deployed on in Europe. These nonmilitary personnel are part of the United Nations Interim Administration Mission in Kosovo (UNMIK), which was established in 1999. Most of these few observers and civilian police personnel are from other European countries, as can be seen in Figure 4.

(10.) Source: International Peace Institute (2017); calculations done by authors.

(11.) Source: International Peace Institute (2017); calculations done by authors.