The Past, Present, and Uncertain Future of Collective Conflict Management: Peacekeeping and Beyond

ABSTRACT

Many scholars contend that United Nations peacekeeping has entered a period of transition, but there is little consensus about the nature of this transition or where it may lead. This article seeks to place these debates into a broader theoretical and historical context. Peacekeeping, I argue, is but the latest instantiation of ‘collective conflict management’ (CCM), which has taken many different forms in the past and likely will again in the future. In particular, this article seeks to explain the international systemic conditions that give rise to, and transform, CCM over time.

KEYWORDS:

• peacekeeping
• peace operations
• peacebuilding
• United Nations
• conflict management

United Nations (UN) peacekeeping, according to many scholars, has entered a period of transition – but towards what exactly? Since the mid-twentieth century, the UN and regional organizations have deployed scores of peacekeeping missions, or multilateral contingents of military and often civilian personnel with mandates to prevent conflicts or to oversee ceasefires and peace agreements.¹ Several observers of these operations have recently argued that peacekeeping is facing a period of change and perhaps even ‘crisis’ (Autesserre 2019; Kenkel and Foley 2021), due to the shortcomings of recent operations, growing discord among the permanent members of the UN Security Council, the perceived failure of prevailing ‘liberal’ peacebuilding approaches that promote democratization and marketization, or other purported causes. However, there is little agreement about which problems are principally responsible for propelling peacekeeping into a period of transition, or about where this transition may be leading.

This diversity of views is not surprising – disentangling complex trends is a challenging task. But there appears to be a further impediment to scholarly analysis of peacekeeping’s prospects: a dearth of theoretical frameworks to guide such investigations, especially frameworks that can explain how international conditions shape peacekeeping. To date, theorizing about these operations has focused mainly on the characteristics of the missions, themselves, and of the local contexts in which they operate. I call these ‘micro’ theories of peacekeeping.² Although the ‘macro’ relationship between international politics and peace operations has attracted growing attention,³ many discussions of peacekeeping’s future have left their theoretical assumptions unstated. This is problematic. Without explicit theories of change to ground such analyses, it is difficult to assess competing claims about peacekeeping’s purported transformation, or even to distinguish significant trends from less significant ones.

Another impediment to ‘macro’ theorizing has been a tendency to define the subject too narrowly. Most scholarly works on peace operations (including by this author) have focused on missions authorized by the United Nations since the end of World War II and particularly since the end of the Cold War. This scope of analysis has enabled researchers to investigate changes within the practices of peacekeeping, but limited their capacity to explain changes of peacekeeping into something else – say, into another form of collective conflict management that bears little resemblance what is generally recognized as a ‘peace operation’. What if peacekeeping were, in fact, an instance of a broader phenomenon that has taken very different forms in the past? Might it also do so in the future?

This article argues that peacekeeping is, indeed, the latest instantiation of a larger phenomenon that I call ‘collective conflict management’ (CCM), or multilateral action aimed at managing or obviating threats to international peace and security.⁴ All such arrangements, I contend, rest on shared ideas about what counts as a ‘threat’ to the international system – as perceived, in particular, by the major powers of the day, or those states with the greatest economic and military power. A CCM arrangement is unlikely to take shape in the absence of a major-power consensus, be it explicit or implicit, about the nature of ‘threats’ to the international system. Similarly, if an existing consensus weakens or transforms due to shifts in the ranks of major powers or to changes in their understandings of international security, any CCM arrangement built upon the old consensus will also eventually change, either by adapting to a new consensus (if one forms), fragmenting (if the arrangement itself becomes a source of contention between the major powers), or falling into desuetude.

This theoretical framework is deliberately spare. My goal is not to present a comprehensive account of CCM, but to show how just two properties of the international system – the distribution of material power across states, and the distribution of ideas about what counts as an international security threat – can explain the broad evolution of CCM mechanisms over time. To probe this framework's plausibility, I examine four historical instances of CCM: (1) the nineteenth-century Concert of Europe, in which the continent’s major powers cooperated in managing local conflicts that they considered threats to European stability, (2) the period after the World War I, when a more limited CCM mechanism focused on redrawing borders to avoid future nationalist conflicts, (3) the period from 1945 to 1989, when conditions for CCM were even more limited but sufficient to sustain traditional UN peacekeeping, and (4) the post-Cold War period, when UN peacekeeping morphed into operations with more expansive functions. As we shall see, the scope and substance of CCM in all four periods largely matched major powers’ shared understandings about what constituted an international security threat. Moreover, when this consensus diminished or disappeared due to power shifts or other developments, existing CCM mechanisms changed accordingly – by adapting, fragmenting, or fading away.

Although this framework requires further development, it offers one possible theoretical foundation for debates about peacekeeping’s future, including the possibility that new forms of CCM may emerge to compete with, or supplant, contemporary peace missions. It also raises doubts about whether ‘pragmatic’ peacekeeping (Dunton, Laurence, and Vlavonou, 2023) is even possible, given that all CCM systems presuppose the existence of historically contingent understandings of international ‘threats’ and ‘stability’. Put differently, every instance of CCM – including peacekeeping in its various forms – both reflects and enacts a political ideology.

The remainder of the article is in four parts. First, I review recent debates on the future of peacekeeping and argue that they would benefit from a stronger theoretical grounding and a broader historical scope. Second, I present the outlines of a theory about the relationship between international systemic conditions and CCM. Third, I evaluate four historical CCM periods through the lens of this theoretical framework. Finally, I discuss the requirements for further developing and then applying this framework to contemporary debates about peace operations, including recent discussions about the rise of ‘pragmatic’ peacekeeping.

The ‘crisis’ in peacekeeping

Although peacekeeping appears to be thriving according to some metrics – nearly 74,000 uniformed personnel from 121 countries were serving in 12 UN peacekeeping missions as of late 2022 (United Nations 2022b) – recent developments have prompted analysts to question the future of this conflict-management instrument (Coleman 2020). Between 2015 and 2022, no large UN missions were created and several existing ones were shuttered, resulting in a 31 percent drop in the number of deployed personnel and a 22 percent cut in the peacekeeping budget over this period (United Nations 2015, 2022a, 2022c).⁵ Mounting tensions between the Security Council’s permanent members – especially the United States, Russia and China – contributed to this decline by making it harder for the Council to approve new operations (Boutellis 2020). Other factors weakening peacekeeping may have included the disappointing outcomes of recent missions (Gowan and Stedman 2018), the tendency of international peacekeepers to employ ‘top-down’ methods that prioritize strengthening central state institutions over addressing the local sources of conflict (Donais 2009; Autesserre 2014, 2017), concerns that some operations have aligned themselves with repressive national governments (Billerbeck and Tansey 2019; Laurence 2019), the controversial shift towards more war-fighting ‘robust’ mandates (Peter 2015; Curran and Hunt 2020), high-profile failures to protect civilian populations from harm (Shesterinina and Job 2016) and the perceived shortcomings of liberal peacebuilding approaches (Paris 2010; Campbell 2018).

There is little agreement, however, about which of these problems poses the greatest risk to peacekeeping. Whereas Gowan (2020b), for example, contends that major-power tensions have ‘effectively ruled out the use of peacekeeping as a conflict resolution tool in a number of geopolitically significant conflicts’, Karlsrud (2019, 2) suggests that the main problem is that ‘liberal peacebuilding has been more difficult than anticipated, fraught with challenges and confronted with a continuing difficulty of understanding local politics and dynamics’, while Osland and Peter (2021, 198) argue that ‘UN peace operations are seen to be in crisis because the UN and multilateralism are in crisis’. Although some scholars also emphasize peacekeeping’s ‘adaptive’ qualities and its capacity to ‘evolve’ (De Coning 2018; Coleman and Williams 2021), most suggest that peacekeeping is nevertheless facing a period of ‘crisis, contestation, or at the very least transition’ (Kenkel and Foley 2021, 190).

But a transition towards what exactly? Analysts have predicted many possible futures. Coleman and Job (2021, 1451), for example, posit that ‘a Chinese and African-led coalition’ of states might jettison ‘the most liberal democratic aspects of peacekeeping and seek to replace western dominance with increased regional influence over UN peacekeeping decisions in Africa and greater Chinese influence in and beyond the Security Council’, although the same authors also note that prevailing liberal approaches have demonstrated ‘resilience’ (1456). Karlsrud (2023) suggests that we have witnessed ‘the end of the liberal moment in UN peacekeeping’ and proposes a new type of ‘UN Support Mission’ largely stripped of liberal content. Dunton, Laurence, and Vlavonou (2023) and Cassin and Zyla (2023) describe the apparent shift towards more ‘pragmatic’ forms of peacekeeping, which the latter authors describe as a ‘normatively flexible’ approach to promoting peace. Meanwhile, De Coning (2021) considers the short, medium and long-term prospects for peacekeeping. Budget cuts and the lingering impact of COVID-19 pandemic, he argues, will likely lead the UN away from large operations and ‘towards a variety of smaller more specialized peace operations’ in the short term. Over the medium term he anticipates that ‘uncertainty and turbulence associated with a significant shift in the power-distribution in the global order’ will foster a ‘conservative’ approach by the Security Council, limiting the creation of major new operations; and in the longer-term (beyond 15 years) he expects the UN to recover enough ‘space again to play a more prominent role in maintaining international peace and security’, including through peacekeeping. Other analysts, such as Osland and Peter (2021, 198), similarly suggest that peacekeeping should adopt more ‘stripped-down’ mission mandates prioritizing the rule of law and ‘bottom-up’ initiatives, while Richmond (2022) contends that ‘international peace architecture’ might deepen its commitments to rights and sustainability, among other things.

While these assertions are reasonable, the assumptions underpinning them are often unclear. On what basis should we expect a transformation of peacekeeping, and why in one direction or another? Put differently, what theories of change underpin these various prognostications?

Systemic drivers of collective conflict management

A theory of change is a general explanation for the appearance, disappearance, or transformation of something – in this case, CCM. A traditional distinction in the study of international relations is between systemic and unit-level theories of change. Systemic theories focus on the properties of the international system as a whole – such as the distribution of material power or of dominant ideas – to explain certain phenomena, whereas unit-level theories attempt to explain these phenomena in relation to the internal properties of the system’s units: typically, states. It follows that a systemic theory of CCM change focuses on the system-level factors producing and shaping CCM. This necessarily involves a simplification of complex reality. No theory can account for every aspect or every driver of change. Rather, seeks to highlight and explain important patterns.

As noted, this article focuses on two properties of the international system – the distribution of material power across states, and the distribution of ideas about what counts as an international security threat – to explain broad shifts in the CCM, of which peacekeeping is one manifestation. I advance three specific propositions: First, the key enabling condition for CCM is the existence of shared understandings among the major powers about what constitutes an international security threat. Second, the content of these understandings delimits the purposes, and to some extent the methods, of CCM. Third, if major powers’ perceptions of the sources of insecurity become less congruent, either because of changes within their respective understandings or because new powers come to the fore with competing conceptions of international order, CCM will change accordingly. It may do so by: (a) adapting to a revised major-power consensus on the sources of insecurity, if such a consensus forms; (b) fragmenting, if the CCM mechanism itself becomes a source of contestation among the major powers; or (c) fading into irrelevance. These changes may not happen immediately, but they are inevitable.

Why focus on power and ideas?

I have defined CCM as multilateral action aimed at managing or obviating threats to international peace and security, which implies more than the simple fact of cooperation among multiple actors. As Ruggie (1992, 567) explains: ‘what is distinctive about multilateralism is not merely that it coordinates national policies in groups of three or more states, which is something that other organizational forms also do, but that it does so on the basis of certain principles of ordering relations among those states’. By highlighting ‘intersubjective understandings as a major factor in sustaining international regimes’ (Ruggie 1998, 3), his depiction of multilateralism echoes core tenets of constructivist international relations theory. CCM similarly rests on a sense of shared social purpose, stemming from common understandings about what counts as a ‘threat’ warranting a collective response, although CCM is agnostic about what these perceptions might be. In principle, virtually anything could be defined as a threat or ‘securitized’ (Buzan, Wæver, and de Wilde 1998).

Students of peace operations have detailed the complex constellation of actors participating in, and influencing, these missions. They include international and regional organizations, troop-contributing states, donor countries and institutions, non-governmental organizations of various types, and of course individuals and groups within the state ‘hosting’ the operation. The theory of CCM presented here, however, focuses on just a few actors: countries with the greatest military and economic resources, which generally have superior capacities not only to contribute to CCM but also to block collective action should they choose to do so. This is not to suggest that other actors are unimportant. Rather, as Wendt (1992, 9) notes in another context: ‘The point is merely that states are still the primary medium through which the effects of other actors on the regulation of violence are channeled into the world system’. The drafters of the UN Charter presumably were aware of this when they decided to grant the Security Council (including its five veto-wielding ‘permanent’ members) the sole power to authorize UN enforcement operations. This was, in the words of one analyst, a ‘conscious compromise’ between the sovereign equality of all UN member states and the reality of their unequal material power (Clark 2017, 251), or what another scholar has termed ‘legalized hegemony’ (Simpson 2004, 6). Indeed, powerful states have long enjoyed ‘special responsibilities’ for managing collective problems such as international security (Bukovansky et al. 2012). It is difficult to imagine how a CCM system could function without at least the tacit support of such states. For all these reasons, I posit that the perceptions of major powers about what counts as a security threat are crucial for explaining the presence, absence, and transformation of CCM, not unlike the approach taken by Fanny Badache, Sara Hellmüller and Bilal Salaymeh (2022) in their analysis of how powerful states perceive peace operations.

But how do major powers conceive of international security threats? The realist school of international relations offers one possible answer: In the absence of a world government, states must ultimately rely on themselves for their survival by building defensive capabilities and forming alliances with other countries to ensure that potentially hostile states cannot dominate them. According to this view, states assess security threats based on calculations of potential adversaries’ material capabilities.⁶ In critiquing this account, however, other scholars highlight different factors shaping states’ perceptions of external threats, including the psychology of national leaders (Jervis 1976), the organizational properties of their governments (Allison 1969) and the dynamics of domestic politics (Fearon 1998). As Stein (2013, 365) summarizes: ‘Threats do not unambiguously speak for themselves’.

Finnemore (2003) offers a different answer to this question, arguing that states’ perceptions of external threats reflect their respective understandings of the ‘international order’, defined as the ‘regularized patterns of behavior among states, which some might call the structure of the system and others the rules of the system’ (85). An international order, she further explains, includes ‘understandings about desirable political goals and legitimate or effective political means’ (85), together with assumptions about the ‘rights and obligations of states toward one another, about what is a threat, and about what are effective and legitimate uses of state power’ (93) and the ‘mechanisms by which order is to be maintained’ (86). Finnemore’s constructivist account departs from realism by emphasizing the fundamental importance of shared ideas, but she notes that these understandings are not disconnected from material power: ‘To the contrary, rules about intervention are strongly if not entirely shaped by the actions of powerful states that actually have the capacity to intervene’ (5). Major powers’ conceptions of order (and, conversely, their perceptions of what poses a threat to international order) thus establish the ‘boundary conditions on the types of orders’ that are practically possible (95).

Finnemore’s blend of ideational and material considerations offers a useful basis for theorizing about the establishment of CCM mechanisms and why they might change. Provided that major powers share common threat conceptions – whatever they may be – CCM should be possible. Conversely, if there is little convergence in these conceptions, the prospects for collective action should be limited. These ideas should also define the purposes and methods of CCM: preventing the proliferation of nuclear weapons, for instance, will entail different responses than, say, ending civil wars or confronting transnational ‘terrorism’.

But what if major powers hold competing views about threats to international order? While a CCM mechanisms need not be universally endorsed, their character as collective arrangements and as conflict management systems would be called into doubt if such mechanisms, themselves, became points of conflict among the world’s most powerful states. Some measure of consensus, in other words, is a precondition for CCM.

CCM and change

A major-power consensus may weaken or disintegrate for any number of reasons. Domestic political transformations, ranging from revolutions to simple changes in government, may displace previously orthodox perspectives within key states. The global distribution of material capabilities might also change, elevating new powers that hold different ideas about the nature of international security threats. Unexpected ‘shocks’ may expose the shortcomings of existing CCM methods or focus attention on new security risks. Whatever the cause, however, if a major-power consensus weakens or disappears, related CCM mechanisms should change accordingly, although perhaps not immediately. As numerous scholars have explained, international institutions can be ‘sticky’, persisting beyond the conditions that created them if, for instance, these institutions continue to serve useful roles such as facilitating cooperation, lowering transaction costs and reducing uncertainty (Keohane 1984). States might also choose to sustain institutions that burnish their own ‘status’ as leading countries (Howard and Dayal 2018; Fung 2019) or simply out of ‘habit’ (Hopf 2010). Arguments about institutional stickiness, however, are never absolute. If a CCM system ceased to reflect the shared security assumptions of major powers, it would become ripe for change. Eventually, it should either adapt to a new major-power consensus (if one forms), fragment (if it becomes a source of contestation among major powers), or fall into disuse, perhaps to be supplanted by competing mechanisms.

These propositions might seem self-evident to some readers, including scholars who have recently reflected on the potential impact of China’s rising power on UN peacekeeping (e.g. Fung 2019; Foot 2020; Zürcher 2020; Howard 2021; Uesugi and Richmond 2021). As with other discussions about anticipated transformations of peacekeeping, however, there is little agreement on the answer to this question. While some commentators maintain that China has largely accepted, or at least tolerated, existing peacekeeping policies (Cabestan 2018; Gowan 2020a), others warn that China could upend these policies, or contend that it has already chipped away at long-standing UN practices and norms – for example, by reformulating the ‘responsibility to protect’ concept and to attempting to change UN human rights approaches (Jones 2018; Foot 2020). If anything, this debate underscores the importance of identifying and evaluating the theoretical assumptions that underpin all such analyses. Again, clarifying how systemic conditions interact to produce and to alter CCM mechanisms may provide the foundations for a more systematic and cumulative research programme – in lieu of the current jumble of competing predictions.

Collective conflict management in four eras

Do previous instances of CCM follow the patterns I posited above? To answer this question, I next examine four historical cases: the Concert of Europe’s management of local conflicts in the early nineteenth century, the League of Nations’ efforts to reduce conflicts by facilitating the redrawing of European borders after the World War I, UN peacekeeping during the Cold, and the more expansive form of peacekeeping that has characterized the post-Cold War period. I ask the following questions of each case: Who were the major powers? What did they regard as the principal threats to international security and as appropriate remedies to these threats? Did collective conflict management mechanisms align with these understandings? Finally, what instigated the end of the CCM system or its transition to another arrangement?

The Concert of Europe

The Concert of Europe was a system of consultation and coordination among the major global powers of their day – Prussia, Russia, Austria, Britain and France – that lasted from 1815 until 1848, and to a lesser extent until 1856 (Barkin and Cronin 1994).⁷ The mechanism contributed to decades of relative peace in Europe, while also facilitating the major powers’ collective response to conflicts and perceived threats within smaller European countries.

As the Napoleonic Wars neared an end in 1814, more than 200 European states and principalities met at the Congress of Vienna to organize the post-war European order. In practice, however, only ‘a tight circle of the materially strongest powers’ decided the major issues (Mitzen 2013, 90–91). They were convinced that ‘that the preservation of the system was more important than any single dispute’ and that ‘differences should be settled by consultation rather than by war’ (Kissinger 2014, 61) and committed to ‘renew their meetings at fixed periods … for the purpose of consulting upon their common interests’ (Mitzen 2013, 96). They also agreed to prohibit any unilateral redrawing of European boundaries without the consent of, or at least consultation with, all five powers acting in ‘concert’.

The resulting CCM mechanism sought to minimize the risk that local strife might escalate into a threat to ‘European stability’. It was based on an overlapping set of beliefs and assumptions about what constituted security threats. The lesson the European powers had taken from the French Revolutionary and Napoleonic Wars was that the spread of revolutionary nationalism posed a grave threat to continental peace and to their own survival. This belief was particularly strong among the absolutist monarchies – Prussia, Austria and Russia – whose leaders viewed such revolutionary movements as existential challenges to their own regime’s legitimacy and stability, but as Jervis (1982) points out, the concern was also shared by the leaders of Britain, who were more inclined to support liberal causes, and of France, which was now a constitutional monarchy under the newly-restored Bourbons. Even for these more liberal powers, the Concert provided ‘security against the revolutionary embers more or less existing in every State of Europe’ and upheld ‘established principles of social order’, in the words of Britain’s then-foreign secretary Lord Castlereagh (quoted in Holbraad 1971, 119). Indeed, although the five states interpreted the requirements of European order in their own ways, all of them were ‘suspicious of the growing agitation for parliamentary representation and workers’ rights, not to mention national liberation’ through to the 1850s (Mazower 2012, 9). As Rendall (2007, 286) puts it, they ‘shared enough of a common standard of legitimacy’ to make the Concert work – at least for a time.

Their approach to CCM mirrored these shared understandings. The Concert intervened in civil revolts in Spain, Portugal, Piedmont, and Naples to contain nationalist uprisings and uphold monarchical rule, a practice that liberal Britain resisted but not to the point of endangering the continuation of the Concert (Richardson 1999). In two other cases, the five powers collectively managed nationalist unrest by accepting new states – Greece and Belgium – into the European system, requiring ‘their establishment as monarchical states with ties to recognized European royal family’ (Cronin 1998, 167). These common approaches reflected the major powers’ ‘shared fear of unrest’ and their general belief that maintaining domestic order within other European states was critical to their own security and that of the entire continent (Jervis 1985).

As memories of the French Revolution and the Napoleonic Wars faded, however, divisions between the powers grew more pronounced and the self-restraint and ‘systemic thinking’ that had united the Concert diminished (Schroeder 1986). A shared desire to prevent revolutions from undermining continental security was no longer sufficient to bridge the growing gulf between the conservative powers and the more liberal ones. Britain and France, in particular, came to suspect the other three major powers of ‘using the excuse of suppressing dangerous revolutions as a cover for expanding their influence’ (Jervis 1982, 368). Although the ideational foundation that supported the Concert’s approach to CCM had always been shaky, the system had nevertheless continued to function ‘because a great-power consensus persisted that transcended political ideology’ (Elrod 1976, 171–172). By the end of the Belgian crisis in 1831, however, discord over whether and how to respond to liberal uprisings had effectively rendered the Concert mechanism moribund. The anti-monarchical republican revolutions that swept Europe in 1848 further widened the ideological gap between the Western liberal powers and the Eastern conservative ones (Kupchan 2010).

Interestingly, Austria, Prussia and Russia continued to invoke the Concert ‘to justify the doctrine of conservative and anti-revolutionary intervention’, against the wishes of Britain and France (Lascurettes 2017, 14). Nonetheless, by now the CCM mechanism had fragmented and become a point of contention, not cooperation. The rituals of Concert diplomacy persisted for decades, with all of the major powers periodically pledged to manage disputes for the good of ‘European order’,⁸ but their words rang hollow as the same countries increasingly treated local conflicts as opportunities to gain advantage over each other – an approach that ultimately enabled a single gunman in Sarajevo to spark World War I.

The League of Nations

The unprecedented devastation of 1914–18 prompted post-war leaders to establish another CCM mechanism centred on the newly created League of Nations. At the League’s core was a collective security system in which all member states pledged to resolve their disputes peacefully and to take military action only if called upon to do so by the League. Unlike the Concert of Europe, the League was a formal organization with a headquarters and staff, and its membership included both large and small countries, including several non-European ones. However, its collective security system was still managed by a select group of states in the League’s ‘Council’, included five major powers designated as permanent members – Britain, France, Italy, Japan and the United States. A detailed explanation of why this system failed is beyond the scope of this article; suffice it to say that these powers – including the United States, whose Senate blocked its participation in the League – were unwilling to make the diplomatic and military commitments necessary to counter aggression during the interwar period. Barros (1964, 378) expresses this point succinctly: ‘no international organization established along League lines could be successful unless possessing Great Power consensus’.

Yet there was more to the League’s security arrangements than its stillborn collective security system. Like the victorious coalition that emerged from the Napoleonic Wars perceiving revolutions as an immediate danger to European security, the winners of World War I had distinctive ideas about what counted as an international security threat. US President Woodrow Wilson, leading a country that had clearly entered the ranks of major powers, was particularly influential in this regard. His ‘Fourteen Points’ represented a set of ideas and assumptions that would inform postwar conflict management, including the belief that a failure to ensure the self-determination of nations risked further unrest and war. This belief stemmed from his and others’ assessment that unrequited national aspirations of groups living under ‘foreign’ rule had been among the causes of World War I. To fix this problem and to reduce the risk of future conflagrations, the victorious powers divided the erstwhile German and Austro-Hungarian empires and sought to align European borders more closely with the actual geographical distribution of different national groups. Although Britain and France were initially skeptical of Wilson’s ideas, by the end of the war both had come to accept them (Barkin and Cronin 1994), making the principle of ‘national self-determination’ a centrepiece of the postwar settlement.

These ideas informed the major powers’ CCM activities after the war. One such approach used plebiscites to ask populations in border zones to indicate where they wished new frontiers to be drawn. Inter-allied commissions oversaw five such votes in 1920 and 1921 in Schleswig, Allenstein and Marienwerder, Klagenfurt, Upper Silesia, and Sopron (James 1999). Multinational military contingents were deployed to provide security and ensure fair referenda in certain cases – a precursor of modern peacekeeping. To the same end, the League also established expert commissions of enquiry to bring boundaries into alignment with the distribution of national groups, and temporarily assumed administrative authority over two contested territories (James 1999; MacQueen 2006).

This flurry of activity by the victorious powers and the League of Nations dissipated by the 1930s. Major-country tensions had effectively paralyzed the League, although the organization persisted for years as an increasingly empty shell. Nevertheless, for a brief period after the World War I, a modest CCM system – based on a real, if fleeting, major-power consensus about what constituted a threat to international security – had facilitated the collective redrawing of boundaries and management of disputed border territories.

Cold War-era peacekeeping

Efforts to establish a durable basis for international order resumed before the end of World War II, when the leaders of the United States, Britain and the Soviet Union met on several occasions to discuss the design of the postwar international institutions. The UN’s new Charter empowered members of the Security Council including five permanent members – the major powers of the day – to ‘determine the existence of any threat to the peace, breach of the peace, or act of aggression’ and to ‘decide what measures shall be taken’, up to and including military force, in order ‘to maintain or restore international peace and security’ (Article 39). The shadow of the League and its Council were clearly visible in this design, but there were significant differences, including the major powers’ perception that virulent nationalism, most notably in the form of fascism, had been a principal cause of the war and remained a major threat to international security (Barkin and Cronin 1994). This contrasted with the League’s attempts to strengthen peace by enabling nationalism and redrawing borders around nationalities to avert renewed conflict. Although self-determination after 1945 became a synonym for European decolonization and the UN supported the transition of former colonies to statehood, the principle was no longer considered a basis for dissatisfied minorities in already-independent states to claim rights to their own separate sovereignty (Mayall 1992). Protecting states from external aggression and sustaining their frontiers effectively trumped other values in the Charter as the basis for maintaining international peace and security (see Article 2).

The Cold War quickly shattered hopes of activating the UN’s full collective security system. As the United States and Soviet Union built rival ‘spheres of influence’ comprising allies and client states, they came to use their respective vetoes in the Security Council to block each other’s resolutions. This contest also had a strong ideological element: both ‘superpowers’ viewed each other’s domestic political system as an existential threat and believed that a world consisting of countries more like themselves would be a safer one. Their perceptions of the primary risks to international security thus diverged markedly – if anything, they were mirror images of each other. Both the US and USSR tended to regard civil unrest in third countries as zero-sum competitions for global influence and supplied their respective allies and clients with assistance to resist the encroachment of the other superpower and to suppress domestic unrest. Nevertheless, their understandings of security threats were not entirely incompatible: both countries recognized that local conflicts risked escalating into global (and possibly nuclear) war, and they went to considerable lengths to keep their military forces from directly encountering each other. They also viewed national boundaries as indispensable to international security and thus largely upheld the territorial status quo, rather than seeking to redraw or erase national frontiers, and they occasionally cooperated to prevent local conflicts from spreading.

One prominent instance was the Suez Crisis of 1956, when Britain and France used Israel’s military incursion into Egypt as a pretext to deploy their own troops to regain control of the Suez Canal zone. The Soviet Union then warned that it was prepared to fire nuclear missiles at the intervening countries unless they withdrew their forces. The White House, surprised by the Anglo-French intervention, sought to deescalate the crisis. A flurry of international diplomacy led to the creation of the UN’s first major peacekeeping operation: a lightly armed force of approximately 3,000 troops from third countries, ordered to oversee the departure of foreign forces from Egypt and then to take up monitoring positions along the Egypt-Israeli border. The mission’s mandate prohibited UN troops from using force (other than in self-defence) and from interfering in the domestic politics of Egypt, principles that became the touchstone for peacekeeping in subsequent years, including in Cyprus and Lebanon. Peacekeeping operations, wrote UN Secretary General Dag Hammarskjöld at the time, must be limited to addressing the ‘external [international] aspects of the political situation’, or else ‘United Nations units might run the risk of getting involved in differences with local authorities or [the] public in internal conflicts which would be highly detrimental to the effectiveness of the operation’ (quoted in Paris 2004, 14).

These principles reflected the limited consensus on CCM that existed at the time. As Barnett (1995, 87) puts it, ‘peacekeeping forces became a highly useful instrument to encourage juridical sovereignty and territorial integrity and to defuse potential superpower conflict’. The limited scope of this consensus became evident in the 1960s, when a UN peacekeeping mission in the former Belgian Congo became deeply embroiled in the country’s civil conflict, whose competing parties were respectively backed by the US and the Soviet Union. The ensuing controversy nearly ended the practice of peacekeeping, but a reaffirmation of ‘traditional’ limitations on such missions – the peacekeeping principles established during the Suez operation – ultimately brought the CCM mechanism back into line with the narrow scope of the underlying major-power consensus. Still, it would be a mistake to characterize traditional peacekeeping as normatively neutral even with regards to the internal governance of the countries hosting these missions. By sanctifying national boundaries and elevating juridical sovereignty above other values, traditional peacekeeping effectively promoted a statist vision of raison d’état (Barkin and Cronin 1994; Barnett 1995).

Post-cold war peacekeeping

The three CCM mechanisms described above were established in the wake of devastating wars. The Cold War, by contrast, ended with more of a whimper than a bang, but the collapse of the Soviet Union and its political ideology represented as profound and sudden a shift to the global power hierarchy as any war. The bipolar world abruptly became a unipolar one in which the United States dominated both economically and militarily (Krauthammer 1990). Liberal political and economic thought also appeared to be triumphant (Fukuyama 1989).

These changes once again shaped the development of CCM. A new kind of peace operation, broadly labelled ‘liberal peacebuilding’, reflected the sole remaining superpower’s security assumptions, including its view that liberal market democracies fostered peace both within their internal politics and in international relations. ‘Ultimately, the best strategy to ensure our security and to build a durable peace is to support the advance of democracy elsewhere’, announced US President Bill Clinton in 1994.⁹ This ‘liberal peace’ thesis became an organizing idea for major international institutions in the post-Cold War period, as UN secretary general Kofi Annan explained: ‘There are many good reasons for promoting democracy. Not the least – in the eyes of the United Nations – is that, when sustained over the long term, it is a highly effective means of preventing conflict, both within and between States’ (United Nations 2000).

From the perspective of decision-makers in Washington, the end of US-Soviet rivalry reduced the strategic importance of conflicts in parts of the ‘periphery’, including much of Africa. This created a further incentive to delegate conflict management responsibilities to the UN and other international institutions. A dramatic rise in mediation processes ended in a flurry of new peace agreements and a growth in UN missions, many deployed to help implement these agreements (Gowan and Stedman 2018). The Security Council authorized 37 new missions in the first decade after the Cold War (1989–99), compared to just 15 created in the preceding four decades (1948–88).¹⁰ The mandates and approach of these missions reflected the distinctively Western or American assumption that political liberalization and economic marketization would provide a foundation for lasting peace. Implementing this vision required deep involvement in the domestic affairs of conflict-affected states – from organizing and conducting elections, to drafting criminal laws, establishing judicial institutions, and guiding economic policies – departing from earlier methods of peacekeeping.

The 9/11 attacks on the US, organized by Al-Qaeda from war-torn Afghanistan, reinforced Washington’s determination to strengthen governmental institutions in any ‘failed states’ that might become havens for transnational militants. George W. Bush had been elected US president in 2000 promising to end US ‘nation building’ activities abroad, but he soon became one of its greatest champions. In the introduction of his government’s 2002 National Security Strategy, he wrote:

The events of September 11, 2001, taught us that weak states, like Afghanistan, can pose as great a danger to our national interests as strong states. Poverty does not make poor people into terrorists and murderers. Yet, poverty, weak institutions, and corruption can make weak states vulnerable to terrorist networks and drug cartels within their borders. (United States 2002)

Rather than abandoning America’s liberal peace assumptions after 9/11, in other words, Bush deepened his commitment to them, including in Afghanistan and Iraq, which US-led coalitions invaded in late 2001 and 2003 respectively. After the initial invasions, the US and its partners sought to remake these countries as liberal democracies. As Bush explained: ‘The survival of liberty in our land increasingly depends on the success of liberty in other lands. The best hope for peace in our world is the expansion of freedom in all the world’.¹¹

Two versions of liberal peacebuilding thus emerged in the post-Cold War years. The first was a multilateral mechanism, organized mainly by the UN, that saw the deployment of complex operations to countries emerging from civil conflicts after the negotiation of a peace agreement. The second version was the more direct form of US-led, post-invasion peacebuilding, where the international peacebuilder was, in effect, the conqueror, but which was also based on the peace-through-liberalization formula. Both bore the unmistakable stamp of the world’s solitary superpower and its assumptions about international order.

However, the scarring experience of failure in Afghanistan and Iraq ultimately fuelled a backlash, in the United States and elsewhere, against intrusive forms of intervention.¹² Frustration at America’s ‘regime change’ invasions also fostered mounting skepticism towards all forms of liberal interventionism (Paris 2010). If the future of peacekeeping is in question today, it is partly because these assumptions about conflict management have been called into question – not just by other countries, but by the US itself.

Refining and applying the theory

All four of these cases demonstrate a close connection between, on one hand, major powers’ beliefs and assumptions about the source of international security threats, and, on the other hand, the character and development of collective conflict management mechanisms. When the security perceptions of the world’s strongest states were congruent, collective conflict management became possible and reflected, in form and substance, these shared understandings. Conversely, when this congruence disappeared, existing CCM mechanisms eventually gave way to something else or simply faded away.

Further refinement of this theoretical framework is needed, including clarification and elaboration of: (1) the relationship between domestic governance systems of the major powers and their perceptions of security threats, (2) the role of external shocks in the formation or dissolution of CCMs, and (3) the continuities and discontinuities of CCM arrangements once they are established. After addressing these three matters, I shall discuss two possible critiques of the proposed approach, then consider its implications for ‘pragmatic’ peacekeeping.

Domestic governance and CCM

The relationship between the domestic governance systems of major powers and their respective threat perceptions deserves closer examination. The conservative Concert powers, for example, regarded nationalist uprisings not only as a threat to their own monarchical legitimacy, but also as a threat to European security. Even Britain and France, the more liberal powers, initially shared the latter concern. When this consensus broke down, however, so did the Concert. Similarly, the League’s CCM mechanism relied on public consultations and local referenda to bring some of Europe’s international frontiers into closer alignment with the principle of national self-determination, based on a shared view among the victors of World War I that unrequited nationalism posed a continuing threat to international peace. A similar pattern also was visible during the Cold War: The United States regarded not just the Soviet Union, but communism itself, as a threat to international security, while Russian leaders conversely saw the United States and liberal capitalism in the same light. This divergence left room for a modest CCM arrangement, based on common beliefs about the sanctity of state frontiers and the importance of insulating local conflicts from the superpowers’ rivalry. Finally, post-Cold War liberal peacebuilding was clearly rooted in the conviction that market democracies were not only the most desirable system of domestic governance but also the belief that spreading this system would foster peace in countries emerging from civil conflict in ‘failed states’ and in international relations more generally. In all these cases, these major powers appeared to perceive security threats though the filter of their own domestic ‘governance schemas’ (Paris 2015).

One implication of this finding is that the prospects for extensive CCM arrangements among major powers with competing regime types may be limited. This would be consistent with recent research on ‘ideological polarity’ and the ‘distribution of identity’ in international politics (Allan, Vucetic, and Hopf 2018). On the other hand, during the Concert era, the perspectives of liberal Britain and France were sufficiently aligned with the conservative European powers to sustain, at least for a time, a robust CCM system. Nor did differing US and Soviet understandings of security threats during the Cold War preclude the development of a peacekeeping mechanism based on shared, if limited, normative assumptions.

Shocks and CCM change

Shocks of various kinds have figured prominently in the case studies examined above. In three of the four cases, new CCM systems emerged after large-scale wars had clarified changes in the international distribution of power and influenced the victors’ ideas about the sources of insecurity (see also Ikenberry 2001). Further, fresh memories of a devastating war may have reinforced motivations to prevent new conflicts. The fourth case, by contrast, followed a different type of shock: a sudden change in the global power hierarchy caused by the collapse of Soviet power. Cold War-era peacekeeping was then remolded to match the conflict management assumptions of the sole remaining great power: the United States. The 9/11 attacks a decade later – another shock – reinforced US policymakers’ beliefs about the security imperative of liberalizing unstable or adversarial states, now through forced democratization. The costly failure of US-led operations in Afghanistan and Iraq then produced yet another shock: widespread public and elite disillusionment with existing CCM methods and assumptions, including peace through liberalization.

Interestingly, though, CCM changes have sometimes occurred without dramatic shocks. As we have seen, the Concert of Europe slowly fragmented and the League’s CCM activities faded away long before the outbreak of World War II. These cases suggest that the creation of CCM mechanisms may be associated with shocks, but their demise may happen more gradually, following changes to the material and ideational foundations that initially gave rise to these mechanisms. Understanding these patterns seems particularly important given current discussions about peacekeeping’s future.

Time lags and institutional stickiness

The preceding discussion raises another question: How can we explain the apparent lag, in some cases, between shifts in the macro conditions that gave rise to a CCM mechanism and the effects of those shifts on the mechanism itself? There were several examples of institutional ‘stickiness’ in the case studies. As noted, European powers continued to enact the Concert’s distinctive rituals even after that CCM mechanism had ceased to function. They may have done so simply out of habit, or to sustain the status of leading powers that these rituals reinforced, but perhaps they were also seeking to legitimize actions that effectively repudiated the Concert’s collectivist management principles: for example, when Russia, Austria and Prussia appropriated the CCM instrument to advance their own agenda against the wishes (and interests) of the other major powers. Casting this behaviour as consistent with the Concert may have sustained the mechanism in name only, but in practice the CCM mechanism had fragmented: it was no longer collective and it had become a source of conflict among the major powers. This example evokes recent scholarship on ‘counternorms’, or the practice by which some states purport to uphold widely recognized international norms but actually seek to undermine them by changing their meaning (Cooley 2015; Ginsburg 2020). Ultimately, the Concert became an extant-but-lifeless ‘zombie’ institution (Gray 2018) – a rhetorical signifier rather than functioning political mechanism. This is one example of institutional stickiness in CCM and of lagged adjustment to changed systemic conditions.

Another example is that of the League of Nations, which continued to meet right up to the outbreak of World War II, long after it had ceased to figure ‘in the thoughts and calculations of policymakers’ (Beck 1995, 185). Perhaps even the persistence of ‘traditional’ principles of UN peacekeeping should be regarded as a form of institutional stickiness. These principles were established in relation to the relatively straightforward, peace-observation missions of the Cold War. Some observers, however, doubt whether these principles have been well-suited suited to the complex and more dangerous environments that peacekeepers have confronted since the end of the Cold War. Nevertheless, they have persisted to the present, even as they have been partly reinterpreted (Laurence 2019).

Yet another example of institutional stickiness might be the ‘recycling’ of older CCM arrangements into newer ones. As noted, the League’s Council echoed the great-power management structure of the Concert, and later provided a model for the UN Security Council. Early UN peacekeeping resembled – and may have taken inspiration from – the League’s temporary deployments of international troops, and post-Cold War peacekeeping build upon the foundations of the Cold War model. As Cottrell (2016, 6) writes, an international institution rarely arises from a ‘blank slate’; it is typically ‘shaped by its forerunners, tempered by past experience, and steeped in cognitive schemes that give meaning to this experience’. This is a central tenet of historical institutionalism and especially of ideas about ‘path dependence’ in the social sciences (Voeten 2019) and it appears to be quite prominent in the history of CCM. Uesugi and Richmond (2021) make a similar point in relation to what they call the international peace architecture, or IPA: ‘The stages in the evolution of the IPA have left sediments consisting of norms, practices, institutions and laws, which have supported the next stage and allowed the praxis of peace to become more sophisticated and complex’ (436). While their depiction of CCM evolving toward greater sophistication is questionable given the spotty history outlined in this article, the detritus of previous CCM systems have clearly provided building blocks for subsequent ones.

Applying the theory

Even in its current skeletal state, the theoretical framework presented in this article could help to clarify the challenges facing peacekeeping today. A starting point for applying the theory is to answer two questions: First, based on this framework and the observed patterns of CCM change in the past, which future scenarios are conceivable for contemporary peacekeeping? Second, what evidence or ‘leading indicators’ would signal that one or another of these futures were materializing? Addressing these questions before investigating current trends would provide a structure for collecting and evaluating evidence, enabling researchers to assess several different possible futures for peacekeeping in the light of ongoing systemic changes.

Possible critiques

At least two critiques could be levelled against this approach. The first is that the framework offers little insight into the everyday dynamics of peace operations, both within the United Nations and in the field. Indeed, there is much that this theory cannot explain and that other theories may be better equipped to elucidate. Many researchers have productively examined smaller-scale shifts in peacekeeping doctrine and methods, including evolving understandings of ‘impartiality’ and the use of force, the interactions between UN headquarters and its field commanders, or the relationships between international actors and the societies ‘host’ missions. All these activities, however, occur within the constraints of a CCM system that is itself subject to periodic changes, replacement, or abandonment. This article has proposed the foundations of a ‘macro’ theory about the systemic drivers of such change. Attention to these forces and how they have shaped CCM in the past would enrich contemporary analyses of ways in which peacekeeping may be changing today – and how it might change in the future. Among other things, the framework allows us to consider futures which might otherwise go overlooked, including the possible rise of new CCM mechanisms that have little resemblance to contemporary peacekeeping. If, on the other hand, micro-level theories do a better job of explaining these patterns than the systemic drivers that I have identified, scholars should make this case. Evaluating competing theories against evidence would strengthen the peacekeeping research programme and advance the larger investigation of CCM.

The second critique is related to the first: that the theory I am proposing is overly spare, even for a macro-level framework. Others have approached ‘macro’ theorizing differently. Richmond (2022), for example, seeks to situate contemporary peacekeeping in ‘a large-scale rather than micro perspective’ by identifying different ‘stages’ in the transformation of conflict management approaches over time: ‘a partially planned, partially fortuitous, partially resisted or blocked, intergenerational set of practices (e.g. military intervention, humanitarianism, peacekeeping, mediation, social movements, etc.) aimed at ending war’ (1, 9). The principal strength of his analysis is its detailed attention to the interplay of ‘elements, actors, systems, scales, laws, institutions, power relations, social movements and networks, customs, and everyday processes’ (33), but its very complexity – verging on unwieldiness – is simultaneously its principal weakness. I have taken a different approach: the theoretical framework outlined in this article is distilled by design. Focusing on just two attributes of the international system – the distribution of material power and of ideas about international security threats – can reveal fundamental patterns in the emergence, disappearance, and transformation of CCM systems.

Implications for pragmatic peacekeeping

As Dunton, Laurence, and Vlavonou (2023) point out, several scholars have argued that we are witnessing, or are likely to witness, a shift in the character of peace operations ‘pragmatic’ peacekeeping. The definition of this term varies across different works. For some, it refers to a more limited or restrained peacekeeping agenda than the more ambitious and intrusive missions of the post-Cold War era, which sometimes sought to remake their host states as liberal market democracies; whereas for others the term seems to connote a more sweeping rejection of ideology: a ‘goal-free approach towards peacebuilding, where the focus is on the means or process, and the end-state is open to context-specific interpretations of peace’ (De Coning 2018, 301; see also Bargués 2020). The distinction between these two understandings of ‘pragmatic’ matters. The first version – in particular, the notion that intrusive forms of peacekeeping will be less likely in the future, due to growing disagreements among the world’s most powerful states over questions of sovereignty and good governance, among other things – is consistent with the theory presented in this article: namely, a weakening of the prevailing major-power consensus about what counts as a threat to international peace and security and about how to respond to such threats. However, this is just one of several possible futures that emerge from the history of CCM.

The second reading of ‘pragmatic’ peacekeeping, involving a renunciation of ‘goals' and ideology, is less plausible. This article has demonstrated how and why peacekeeping and CCM have always rested on shared understandings about peace and stability. Whatever changes may occur within contemporary peace operations, and whatever new CCM mechanisms may emerge in the future, they will necessarily reflect – and enact – assumptions about the political world.

Conclusion

The view that UN peacekeeping has entered a period of transition is widespread among observers of these missions, yet there is little agreement about the precise nature of this transformation or where it may lead. Part of the problem, I have argued, is the dearth of theoretical frameworks to guide such analysis, particularly at the ‘macro’ level of the international system. A further impediment has been the relatively narrow historical scope of most assessments, which have tended to focus on contemporary peacekeeping practices rather than considering them as the latest instantiation of a much older phenomenon – collective conflict management – which has taken different forms in the past and could do so again in the future. To address both of these shortcomings, this article has presented the outlines of a systemic theory of CCM that advances three main propositions: (1) the key enabling condition for CCM is shared understandings among the world’s most powerful states about what constitutes an international security threat; (2) the purposes of CCM systems, once established, will also tend to reflect the content of these shared understandings; (3) if these shared perceptions change, CCM will either adapt, fragment, or fade into irrelevance. Initial findings from four case studies supported to these propositions.

A useful next step would be to elaborate this theory, including by clarifying the relationship between domestic governance systems and international threat perceptions, the role of shocks in CCM change, and other conditions under which such institutions may persist or disappear. Even in its current form, however, the framework presented in this paper may help to sharpen assessments of peacekeeping’s current ‘transformation’, not least by encouraging researchers to make their own theoretical assumptions more explicit.

Acknowledgments

My thanks to the editors of the journal and two anonymous reviewers, as well as the editors of this special section, Caroline Dunton and Marion Laurence, for their comments on previous drafts. I also benefited from feedback from participants at a workshop hosted by the Centre for International Policy Studies at the University of Ottawa in May 2021, including trenchant comments from Cedric de Coning.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Social Sciences and Humanities Research Council of Canada.

Notes on contributors

Roland Paris

Roland Paris is a professor of international affairs and the director of the Graduate School of Public and International Affairs at the University of Ottawa, Canada.

Notes

1 This article uses ‘peacekeeping’ as an umbrella term encompassing the array of UN peace operations, from preventive deployments to post-conflict peacebuilding.

2 On the distinction between ‘micro’ and ‘macro’ approaches, see Paris 2014.

3 These contributions include several works on the implications of global power shifts for peacekeeping, and some that consider peace operations from the perspective of international relations theory, such as Oksamytna and Karlsrud 2020. Some specific ‘macro’ questions have also received considerable attention, including, for example, the relationship between peacekeeping and the politics of the UN Security Council (Dayal 2021; Martin-Brûlé, Pingeot, and Pouliot 2019; Howard and Dayal 2018; Voeten 2005).

4 For a different definition of collective conflict management, see Lepgold and Weiss 1998.

5 Deployed military and police: 73,852 (April 2022) vs. 107,805 (April 2015). Combined budget: $8,276 billion (2015–16) vs. $6.453 billion (2022–23). On the ‘downsizing’ in UN peacekeeping, see Coleman 2020.

6 As Waltz (1979, 64) put it: ‘the means of security for one state are, in their very existence, the means by which other states are threatened’.

7 Jervis (1982) argues that the Concert ended in 1823, whereas Schroeder (1986) says it had lingering effects through the latter part of the century.

8 For example, in the ‘Treaty between Great Britain, Germany, Austria, France, Italy, Russia, and Turkey for the Settlement of Affairs in the East: Signed at Berlin, July 13, 1878’, reproduced in American Journal of International Law 2 (1908), 402.

9 ‘Address Before a Joint Session of the Congress on the State of the Union’ (January 25, 1994), https://www.presidency.ucsb.edu/documents/address-before-joint-session-the-congress-the-state-the-union-12.

10 United Nations, ‘List of Peacekeeping Operations, 1948–2019’, n.d., https://peacekeeping.un.org/sites/default/files/unpeacekeeping-operationlist_3_1_0.pdf.

11 George W. Bush, Second Inaugural Address, January 20, 2005.

12 ‘Most Voters Say No to Further U.S. Nation-Building Efforts’, Rasmussen Reports, 22 August 2016, http://www.rasmussenreports.com/public_content/politics/general_politics/august_2016/most_voters_say_no_to_further_u_s_nation_building_efforts.