Roundtable 12-13 on Peacekeeping in the Midst of War48 min read

Peacekeeping was born in 1948, in the midst of the American civil rights and anti-colonial movements. The basic thrust of the idea was to resolve violent conflict without resorting to violence.  In that sense, peacekeeping is unlike other forms of military intervention because of its foundational principles: consent, impartiality, and the use of force in self-defense (and later in defense of the mandate).  These guiding principles continue to anchor peacekeeping today, even if some of the mechanisms and goals have changed over time.

H-Diplo | ISSF Roundtable XII-13

Lisa Hultman, Jacob D. Kathman and Megan Shannon.  Peacekeeping in the Midst of War.  Oxford:  Oxford University Press, 2020.  ISBN:  9780198845577.

23 July 2021 |
Editor: Diane Labrosse | Commissioning Editor: Manjari Chatterjee Miller | Production Editor: George Fujii


Introduction by Lise Morjé Howard, Georgetown University. 2

Review by Alex J. Bellamy, The University of Queensland. 5

Review by Jessica Di Salvatore, University of Warwick. 8

Review by Abiodun Williams, The Fletcher School of Law and Diplomacy, Tufts University  12

Response by Lisa Hultman, Uppsala University, Jacob D. Kathman, SUNY Buffalo, and Megan Shannon, University of Colorado Boulder 14

PDF Version

Introduction by Lise Morjé Howard, Georgetown University

Peacekeeping was born in 1948, in the midst of the American civil rights and anti-colonial movements. The basic thrust of the idea was to resolve violent conflict without resorting to violence.  In that sense, peacekeeping is unlike other forms of military intervention because of its foundational principles: consent, impartiality, and the use of force in self-defense (and later in defense of the mandate).  These guiding principles continue to anchor peacekeeping today, even if some of the mechanisms and goals have changed over time.

After the peacekeeping failures in Rwanda and Bosnia in 1994 and 1995, a new, central goal in peacekeeping became civilian protection.  Since 1999, the UN Security Council (UNSC) has mandated all complex peacekeeping missions to protect civilians.  Lisa Hultman, Jacob D. Kathman, and Megan Shannon’s new book, Peacekeeping in the Midst of War, assesses whether UN peacekeepers have been achieving this important, mandated goal, as measured in civilian deaths. The authors’ answer is affirmative.  All else being equal, thousands more people die—and would be dying—in civil wars where UN peacekeepers are not deployed.  The book is based on two of the authors’ previous, path-breaking articles that demonstrate that peacekeepers reduce violence between military combatants, and against civilians.[1] In recent years, Hultman, Kathman, and Shannon’s work has helped to build a wave of more than a dozen quantitative studies that have all found, in different ways, that the presence of UN peacekeepers reduces violence during civil wars.[2] The general findings are some of the strongest in all of international relations, probably second only to the democratic peace.

The reviews in this roundtable are thus appropriately laudatory.  At the same time, the reviewers point out various issues with the book, and with peacekeeping in general.  The authors of Peacekeeping in the Midst of War focus on several key mechanisms that they hypothesize peacekeepers use to resolve commitment problems during conflict, including disarming, demobilizing, and reintegrating (DDR) combatants, overseeing ceasefire violations, and providing security. In the first review of this roundtable, Alex Bellamy reiterates the authors’ contention that increased peacekeeping presence aids in these mechanisms, with larger missions being more successful at maintaining the reliable flow of information, commitment to the peace process, disincentives to engage in violence, and safety for civilians.

Bellamy and the second reviewer, Jessica Di Salvatore, both suggest that peacekeepers have proven fairly successful in the somewhat narrow focus of civilian protection and conflict management. However, many of today’s missions (both the stabilization missions within states, and the cease-fire monitoring missions between states) are not moving very quickly toward ending the wars, implementing mandates, and departing.  Although the protection of civilians is a laudable goal, and certainly peacekeepers are achieving this goal, missions are not winding down as quickly as they were in the 1990s and early 2000s.[3]

Di Salvatore supports the authors’ statistical analysis and conclusion that the increased presence of UN troops, police, and observer units aids in reducing violence.  Di Salvatore notes, however, that Peacekeeping in the Midst of War does not adequately explain the causal mechanisms in peacekeeping that serve to reduce violence. She also contends that the authors present a low-bar, “security first” argument that may be more normative than based in evidence. Hultman, Kathman, and Shannon respond by suggesting a variety of ways that future work might tease-out the relative importance of the 5-6 causal mechanisms they explore.  The authors do not contest the “security first” term.  It seems, however, that the introducing the term “security first” is misplaced.  The authors are interested in assessing combat-related death.  Security is not the same thing as the absence of violent death.  Security—what makes an individual or a state feel secure—is much more subjective and broader.  Hultman, Kathman, and Shannon’s approach to measuring violence is not a “security first” approach, rather, they are making the reasonable claim that negative peace—the absence of violent conflict—must usually come before positive peace, even if UN peacekeeping mandates are not consistently clear on this priority.

In the final review in this roundtable, Abi Williams calls for greater attention to the practical and political problems that obstruct mandate implementation.  He raises the issue of disagreements among member states over the distribution of peacekeeping resources and their effects on UN effectiveness as a topic requiring further research.  Williams recalls that originally, peacekeeping was predicated on the notion that there would be a “peace to keep.” Many studies have evaluated peacekeeping along fairly “absolutist” terms of success or failure in mandate implementation—did the peacekeepers full their UNSC-mandated tasks and depart?  This method of evaluation, however, is limited.  Williams points out the value in Hultman, Kathman, and Shannon’s re-casting of how scholars might evaluate peacekeeping.  Since many peacekeeping missions are no longer deployed where there is a peace to keep, and the missions are not regularly ending, it is important to evaluate whether they are accomplishing narrower goals such as reducing military and civilian deaths.  Williams notes that the authors have provided convincing evidence that more peacekeepers correlate with fewer deaths, but he also, like Di Salvatore, invokes the lack of clarity about causal mechanisms suggesting that “it is not so much who participates but how they participate.”

On this point of “who participates and how” it is important to note that the authors exclude civilians from their statistical analyses.  Civilian peacekeepers, however, engage in a wide array of important activities such as mediating conflicts, training future bureaucrats, and monitoring and reporting on human rights and sexual abuse.  The authors depict peacekeeping as primarily a military endeavor, without mentioning civilian control, direction, or action.  Moreover, on Williams’ theme of “who participates and how,” the authors contend that “observers seem to exacerbate violence” because, the authors hypothesize, observers send a signal that the international community is not serious about ending violence, and because they do not have the military capacity to stop violence (94, 125, 126).  This argument is problematic for several reasons.  Violence exacerbation may have many causes (for example, violence has escalated in Syria very often, and without observers).  Moreover, non-violent international actions and signals can have positive effects.  For example, there are currently 700 observers from dozens of Organization for Security and Co-operation in Europe (OSCE) and other states in eastern Ukraine.[4] The OSCE observers track and report every movement in the conflict, and the civil war in Ukraine has one of the lowest death rates of all current conflicts. Civilians and observers play important roles in reducing violence, which are not discussed in the book.  By investigating only the military and police-oriented activities of blue helmets, the book does not address how peacekeepers protect civilian and military lives. The exclusive focus on military-oriented peacekeeping mechanisms also gives rise to limited policy prescriptions.

Importantly, the reviewers praise the authors’ exploration of the negative effects of peacekeeping.  A greater peacekeeping presence reduces violence, but it can bring detrimental impacts to host states.  Bellamy highlights the positive relationship between the size of a mission and the rates of sexual and gender-based crimes committed against local populations.  Di Salvatore focuses on the “economic distortions resulting from the so-called peacekeeping economies.” Both Di Salvatore and Williams reference the Action4Peacekeeping initiative, which is intended to introduce stricter accountability measures to correct for these negative effects.  In their response, the authors affirm the need for greater study to deduce which peacekeeping mechanisms are most effective at violence reduction.  They also echo Di Salvatore’s point that the lack of prioritization in mandates serves as an impediment to peacekeeping success.

To conclude, Hultman, Kathman, and Shannon have produced an important piece of scholarship.  Their book demonstrates that UN peacekeepers reduce violence against civilians, and between combatants.  This is a significant contribution for both scholarly and policy audiences.  It will be important, however, for future studies to dive more deeply into developing a rational theoretical framework that might better account for today’s complex civil war battlefields, with multiple actors, few frontlines, and multiple reasons for fighting.  It would also be beneficial if quantitative qualitative methods-oriented colleagues engaged more regularly with each other.  Peacekeepers are keeping the peace, but how they keep the peace remains a debate.  Answering this question is crucial not only for the sake of honing scholarly analysis, but also for improving policy recommendations and policy action.



Lisa Hultman is an associate professor of peace and conflict research at Uppsala University.  Her research focuses on civil war, international politics of protection, and the consequences of intervention.

Jacob D. Kathman is a professor of political science at SUNY Buffalo.  He studies peace and conflict processes, including issues of peacekeeping, intervention, and civilian victimization.

Megan Shannon is an associate professor of political science at the University of Colorado Boulder.  Her research explores how international institutions influence human and interstate security.

Lise Morjé Howard is a professor of Government and Foreign Service at Georgetown University, and President of the Academic Council on the United Nations System.  She has published extensively on UN peacekeeping, civil war termination, and American foreign policy in such journals as International OrganizationInternational SecurityInternational Studies QuarterlyInternational Peacekeeping, Global Governance, and Foreign Affairs.  She served as lead author for the Effectiveness of Peace Operations Network’s recent evaluation of the UN mission in the Central African Republic.  She is the author of two award-winning books on peacekeeping: UN Peacekeeping in Civil Wars (Cambridge University Press, 2008) and Power in Peacekeeping (Cambridge University Press, 2019).

Alex J. Bellamy is Director of the Asia Pacific Centre for the Responsibility to Protect and Professor of Peace and Conflict Studies at The University of Queensland, Australia.  He Fellow of the Academy of Social Sciences in Australia and has been a visiting fellow at the University of Oxford (most recently 2019-2020).  Recent books include World Peace (And How We Can Achieve It) (Oxford University Press, 2020) and, with Paul D. Williams, Understanding Peacekeeping, 3rd edition (Polity Press, 2021).  He is currently writing a book about the international response to the Syrian civil war.

Jessica Di Salvatore (Ph.D. University of Amsterdam, 2017) is Associate Professor in Political Science and Peace Studies at the University of Warwick (Department of Politics and International Studies).  Her research interests focus on peacekeeping operations, UN peacebuilding and political violence.  She has published her work in American Journal of Political Science, British Journal of Political Science, Journal of Conflict Resolution, Journal of Peace Research, International Peacekeeping and International Studies Quarterly.

Abiodun Williams is Director of the Institute for Global Leadership and Professor of the Practice of International Politics at The Fletcher School of Law and Diplomacy, Tufts University.  He was President of The Hague Institute for Global Justice and Senior Vice President at the United States Institute of Peace.  He was Director of Strategic Planning for UN Secretaries-General Kofi Annan and Ban Ki-moon, and served in three peacekeeping missions in the Balkans and Haiti.  He is past Chair of the Academic Council on the United Nations System (ACUNS) and has published widely on the UN and conflict prevention.


Review by Alex J. Bellamy, The University of Queensland

It is safe to say that beyond the hallowed halls, seminar rooms, and negotiating chambers in and around the United Nations, the practice of peacekeeping does not enjoy a warm reputation in global public opinion.  The political right tends to see it either as a colossal waste of effort and resources expended on war zones with limited political value, a byword for ineptitude and failure, or a combination of both.  The political left often views peacekeeping as a vehicle for militarism, neo-imperial interventionism, sexual exploitation, and abuse, and/or the forcible imposition of capitalism.  There are, of course, grains of truth in all these (and other) criticisms.  Peacekeeping does sometimes fail outright – witness Rwanda, Srebrenica, and, more recently, Syria.  Sometimes expensive missions drag on seemingly without end, as in the Democratic Republic of Congo (DRC).  Some missions do have an appalling track record of sexual abuse and exploitation – the [1999-present] United Nations Organization Stabilization Mission in the Democratic Republic of the Congo (MONUSCO) in the DRC stands out in this regard too but is by no means alone on that score.  Yet for all that, time and again sober assessments of the practice’s overall record – some of which are quantitative, like Virginia Fortna’s landmark study, others qualitative, like Lise Howard’s important work – reveal that civil-war affected countries and the peace settlements they negotiate tend to do better when attended by peacekeepers than those to which no peacekeepers are deployed.[5]

In theory, peacekeeping – a practice begun in ad hoc fashion by the UN in 1948 – was designed to play a very specific set of roles in recently war-torn places that had managed to fashion a peace to keep.  Guided by principles of consent, impartiality, and the use of force only in self-defence, peacekeepers would operate in the critical gap between a credible ceasefire and the termination of hostilities through a peace settlement.  Their role was: to reassure the conflict parties by monitoring compliance with their ceasefire, increasing the political costs of defection, and providing a tripwire should defection occur.  But practice has a habit of not conforming to theory, and in that sense peacekeeping is no exception. Not even the UN’s earliest missions hewed closely to the ideal.

In the Middle East, the United Nations Emergency Force (UNEF) (1956-1967) mission so often taken to be a poster child for ‘traditional’ peacekeeping was actually tasked not just with monitoring a ceasefire line but also with supporting the promotion of human rights in Gaza. In Congo in the 1960s, UN peacekeepers found themselves not just caught up in the midst of war, but actively participating in it. In reality, the ceasefires that brought peacekeepers into a country often quickly broke down, forcing new tasks upon the blue helmets. Thus, peacekeepers in Bosnia, who had initially been deployed (somewhat bizarrely) to monitor a ceasefire in neighbouring Croatia, found their mandate stretched to securing the delivery of humanitarian supplies, monitoring, and sometimes forcibly responding to the use of heavy weapons, and managing so-called ‘safe areas.’ Likewise, peacekeepers in Rwanda, who had been deployed to monitor the Arusha peace agreement, found themselves challenged to protect civilians from genocide.  In Sierra Leone at the turn of the century, UN peacekeepers did more than just monitor the peace, they used force alongside that country’s government and British troops to impose it.  Indeed, of the twelve UN peacekeeping missions ongoing at the start of 2021, seven are deployed in contexts of ongoing or recurrent armed conflict.  Clearly, we need to think differently about how we measure, and understand, the effectiveness of peacekeeping.

That is precisely what Peacekeeping in the Midst of War does. Indeed, so well does it accomplish its task that it is hard to imagine that over the next couple of decades or so anyone will study peacekeeping without referring to it as a critical point of reference.  The extensive research which underpins this study is meticulous.  In their deft handling of the data they present, the authors are thoughtful and reflective.  That should come as no surprise.  The authors, Lisa Hultman, Jacob Kathman, and Megan Shannon, paved the way to this landmark book with a succession of pioneering research articles illuminating aspects of peacekeeping as never before.[6] The result is a book that not only rewards careful reading from beginning to end but that also should sit on the desk, not the shelf: a constant companion for anyone trying to understand peacekeeping.

The basic argument is straightforward enough: that given the right conditions, UN peacekeepers can reduce the violence of civil war (see 4 and 172ff).  Specifically, that the deployment of peacekeepers tends to reduce battlefield casualties and civilian victimization.  The authors marshal a mountain of evidence to sustain that claim most carefully.  What is more, they show that, in general, the greater the number of peacekeepers deployed, the greater these positive effects are likely to be.  These effects are achieved through one or more of four principal mechanism. Peacekeepers can increase the political costs associated with using violence (77ff), improve the ability of combatants to credibly commit to the peace process (16, 50ff), improve the flow of information, and protect civilians from harm (e.g., 4).  All this puts downwards pressure on violence by limiting its utility and increasing its cost.  This central thesis is backed up with so much data and careful analysis that it will be hard to dispute, even though it does strip away what popular culture and political chatter assumes about UN peacekeeping.

But this is not a straightforward “add peacekeepers and stir” type of argument.  Peacekeeping does not unambiguously produce peace, they argue.  Exogenous conditions matter, but so – and this is another important departure – does the nature and composition of the mission itself.  How missions are configured – their size, capacities, conduct, mandate, what they actually do on the ground – influences their likely effectiveness. That is one reason why recent studies on the composition of peace operations and the practices of peacekeeping are so important.[7] It is also why the authors of this book spend so much time thinking about what we mean by, and how we measure, the effectiveness of peacekeeping.  Their answers are illuminating.

The question of how we understand peacekeeping effectiveness has long been a vexed one; there are no good and easy answers.  Indeed, one of the reasons there is so much criticism of peacekeeping is that the expectations attached to it are so unrealistic.  Many accounts judge peacekeeping against arbitrary benchmarks and apply binaries of “success” and “failure.” This approach to measuring effectiveness wrenches states and societies from their own contexts.  Instead of success and failure, the authors of this book insist, we should be looking at whether the deployment of peacekeepers makes things “better” or “worse” than they were before.  Simple binaries also collapse multiple social goods into a single assessment.  A state and a society are a complex thing, with multiple moving parts.  The art of politics is often the art of making trade-offs between different sorts of goods – between security and liberty, for example.  Evaluating peacekeeping is like that too, or at least it ought to be, as Hultman, Kathman, and Shannon explain.

Peacekeepers might on the one hand reduce battle deaths and civilian victimization, whilst simultaneously committing sexual abuse and exploitation, creating sex markets, distorting local economies, and behaving insensitively to local cultures.  To say, as this book does, that peacekeeping can reduce violence is not to say that it does not also generate problems but that with one comes the other.  In fact, sometimes positive and negative are two sides of the same coin.  When peacekeepers establish protection of civilians sites, for example, as they have in South Sudan, they provide a place of sanctuary from immediate physical violence and help reduce overall civilian victimization. But these sites can also encourage civilian displacement and increase the vulnerability to sexual and gender-based violence of the women and girls who are so displaced.  Likewise, with the economy.  Hultman, Kathman, and Shannon show that by reducing violence and injecting resources into often impoverished communities, peacekeepers can open up opportunities for economic recovery and mitigate the effects of the conflict trap, but that by distorting local economies they can also exacerbate existing vulnerabilities and even create new ones.

This book is full of complex trade-offs like this and frank recognition of peacekeeping’s flaws.  But that is balanced by repeated evidence that across different scales and types of violence, war-torn societies with peacekeepers tend to do better than similarly afflicted societies without peacekeepers.  Indeed, they show that whilst larger missions have a greater positive effect on violence, their negative footprints are also necessarily greater.  One of the book’s more important and discomforting observations is that whilst large peacekeeping forces are more likely to reduce civilian victimization overall, they are also more likely to commit their own sexual and gender-based crimes.  Observations like that give us a much more sophisticated account of peacekeeping effectiveness.

Such observations also, however, shed light on practice and policy that could help create an agenda for future reform – one driven by evidence rather than fashion.  Clearly, much more needs to be done to prevent sexual abuse and exploitation by peacekeepers.  That is a well understood priority.  But three other areas of reform, which are perhaps less well understood, are also highlighted by this book.  First, there is a need to think more carefully about peacekeeping economies to reduce negative impacts and exacerbate potential benefits.  Second, if the scale and nature of a mission matters, then we need to know much more about the specific compositions that are likely to have best effect in different sorts of settings.  Third, given the trade-offs, attention needs to be paid to the long-term effects of peacekeeping and to how different actors and institutions can shape those more positively.  Richard Caplan, John Gledhill, Sabrine Karim, Athena Kolbe, and Andrea Ruggeri have already begun a major research project to investigate what happens ‘after exit’), and this book gives further impetus to that line of enquiry.[8]

One of the guiding motifs of Peacekeeping in the Midst of War is the former UN Secretary-General Dag Hammarskjold’s aside that the UN’s function is to save humanity from hell, not take it to heaven. With thorough research and careful evaluation, it succeeds in demonstrating just how peacekeeping contributes to that goal whilst also offering an agenda for research and reform aimed at making peacekeeping a little more heavenly and a little less hellish.



Review by Jessica Di Salvatore, University of Warwick

In 2018, the Department of Peace Operations began working on the Comprehensive Planning and Performance Assessment System (CPAS) with the goal of providing UN peacekeeping missions with a “performance policy framework measuring performance based on data collection and analysis” (UNSC resolution 2436).  CPAS is supposed to be used in all ongoing peacekeeping missions by 2021 and, as surprising as it may sound, it is possibly the very first tool the UN has put in place to evaluate missions’ performances based on outcomes and long-term impact.  In a way, the UN (and possibly the international community) is still wondering whether peacekeeping works and, if it does, how those results can be shown.  It would not be an overstretch to claim that the same spirit of understanding whether peacekeeping works, and, if so, at what exactly, also animates Lisa Hultman, Jacob Kathman, and Megan Shannon’s Peacekeepers in the Midst of War.  The authors not only pose these key questions, but they also guide us through the data analysis and the cases studies that, ultimately, lead them to the conclusion that yes, peacekeeping can work against violence.  But the UN needs to equip missions properly in order to ensure success.

Hultman, Kathman and Shannon explore monthly changes in battlefield violence and violence against unarmed civilians in countries that were at war between 1992 and 2014 in order to assess peacekeepers’ effectiveness against both benchmarks.  Interestingly, the authors devote an entire chapter to discussing their conceptualization of effectiveness as violence mitigation and explaining why it is an important standard (42-44).  And they are right in doing so, because while violence reduction resonates as the most urgent evaluation criteria for missions that are deployed to active conflicts, this is a very low bar, particularly now, at a time when peacekeeping has become increasingly entangled with ambitious peacebuilding goals.  Should we evaluate missions that are mandated to rebuild state capacity as successful if they reduce violence but are unable to carry out any other goal they are mandated with?  Should we assess reduction in violence on a monthly basis or should we look at longer-term indicators?  Hultman, Kathman, and Shannon address these concerns, arguing that security enables the successful implementation of other tasks, hence representing a conditio sine qua non for the overall success of these missions

It is undeniable that pursuing political reforms while citizens’ lives are threatened and governments are busy fighting on the battlefield is unrealistic. To some extent, Hultman, Kathman and Shannon’s stance on the need to establish a safe environment before implementing other tasks may unfortunately be more normative than descriptive of the practice of peacekeeping.  In authorizing new missions and designing their mandates, the UN Security Council (UNSC) does not seem to follow a security-first approach, and tends to authorize overwhelmingly ambitious multidimensional mandates. Hence, the UNSC should not expect missions to be able to even try to carry out tasks when these are practically impossible; and yet, it does.  The book does not directly address this apparent mismatch between which criterion of effectiveness is a priority and what the UNSC (and host countries) expect missions to achieve.  But by showing that peacekeepers can reduce violence, Hultman, Kathman, and Shannon may implicitly have a point.  The UNSC should perhaps seriously consider strategic sequencing and prioritization in mandates, rather than expecting missions to pursue tasks in contexts where they are likely to fail or not even being able to try.[9] This is even more important if the missions’ pursuit of non-security tasks (e.g. organising elections or promoting human rights) during conflict interferes with their capacity to protect by reducing other parties’ willingness to cooperate.[10]

One of the book’s key contributions is defining a metric that makes sense, is observable, measurable, and can be replicated in future studies, as is its stressing of the importance of considering fundamental differences across missions.  As with decision to focus on violence reduction among other possible indicators of effectiveness, in this case the authors focus on the size of missions’ personnel in order to assess which features make some operations better than others at curbing conflict.  The missions they include in their sample range from observers’ missions such as the UN Observer Mission in Liberia (UNOMIL) or the UN Observer Mission in Sierra Leone (UNOMSIL), with no or few military units, to missions comprising thousands of armed personnel such as the UN Organization Stabilization Mission in the Democratic Republic of the Congo (MONUSCO).  Notably, previous studies measured peacekeeping as presence/absence.[11] This scholarship did acknowledge that not all missions are the same, but largely focused on the typology of missions based on their mandates.  Here the authors’ focus on size, however, aims to capture the actual capacity of the mission to operate in the field, regardless of its assumed type.  Before this book was published in 2019, Hultman, Kathman, and Shannon had already published important work measuring peacekeeping in terms of deployment size[12], and that work paved the way for a turn in quantitative studies of peace operations that now cannot avoid considering such important variations in missions’ personnel.  Together, their focus on violence reduction as a criterion for effectiveness and on missions’ personnel has become a standard for the most recent quantitative research on UN peacekeeping.[13]

The book’s focus on the size of UN troops, police, and observer units within peace operations is not only crucial for the purpose of operationalization and accuracy; it is of utmost importance if we want to understand what is about peacekeeping that make it work.  One could argue, for example, that the mere presence of peacekeepers, even if they are not heavily militarized, is a sufficient signal to deter belligerents from using violence.  Belligerents may either fear that the UN is ready to deploy more troops and counter them more proactively, or they may be worried about reputational costs given that the UN is in the field and the international community is watching.  The latter mechanism suggests that peacekeepers can persuade belligerents that violence is not viable regardless of the military costs it involves.[14] Conversely, Hultman, Kathman, and Shannon envision the impact of UN missions as largely dependent on missions’ military power.  In particular, the authors identify five key military activities that peacekeepers carry out and that contribute to mitigate information asymmetries and commitment problems between warring parties (53-59).  These activities entail separating combatants, disarming, demobilizing, and reintegrating them, verifying and reporting violations of the peace process (e.g. ceasefires violations) and providing security behind frontlines.  These tasks are carried out by armed personnel (including police units), and thus already suggest that observers may do little to increase the cost of violence for belligerents.  Indeed, the authors’ statistical analysis confirms that large military contingents give UN missions sufficient capacity to curb battlefield violence and civilian killings on a monthly basis.  The analysis is elaborated and provides several tests to illustrate the robustness of this conclusion.  The robust link between sizeable military deployments and violence mitigation, however, cannot reveal whether the five activities above are indeed the most relevant for success.  As there is no unequivocal link between those activities and the number of UN troops in the field, the statistical analysis is complemented with the case studies of MONUSCO in DRC and the United Nations Operation in Côte d’Ivoire (UNOCI), where some of these activities were carried out.

Although the five activities do provide insights into what UN personnel can do in practice to mitigate violence and increase its cost for belligerents, it is unclear how commonly are these tasks carried out by peacekeepers in civil wars and whether some (or all) are necessary and sufficient for effective violence mitigation.  Take, for example, the separation of combatants.  How is interposition achieved when one of the parties in conflict is the state and the clashes occur in areas with contested control?  In this scenario, how can combatants be effectively separated when there are no clear frontlines and guerrilla tactics are predominant, as occurs in most asymmetric conflicts?  This, in turn, opens up questions about the meaning of the term “behind the frontlines” when frontlines cannot be easily identified.[15] Certainly, some missions are deployed to conflicts that are more suitable to such approaches.  UNOCI, for example, established a zone of confidence from West to East to keep the parties separated and create a buffer.  For this reason, Ivory Coast is an appropriate choice to investigate the contribution of peacekeeping in separating combatants, and to illustrate the role large deployments that enable the mission to control a vast territory effectively.  However, this does not seem to have been the standard tactical approach for other peacekeeping operations.

In fact, Hultman, Kathman, and Shannon use the case of MONUSCO to point out that separation is not always feasible as it might have been for UNOCI; for MONUSCO, the main strategy to control armed groups’ violence was the integration of former rebels into national security forces (153, 158).  Hence, in this case, disarming, demobilizing, and (re)integrating combatants was a more feasible approach than physical separation.  But while separation was sufficient (and probably necessary) to reduce violence in Ivory Coast, disarmament, demobilization, and reintegration (DDR) were not sufficient for that purpose in DRC.  As the authors highlight, MONUSCO had to face more challenges due to the limited incentives for rebels to leave their resourceful groups and become loyal to the government.  Hence, DDR could not be used successfully to solve the commitment problem.  However, the idea that DDR is a tool to address the commitment problem is questioned by the observation that solving the commitment problem may be needed in order for DDR to occur in the first place.  Does DDR carried out by peacekeepers make former belligerents more trustworthy and likely to remain committed to the peace process, or are peacekeepers the reassuring factor that incentivize rebels to go through DDR?  Put it differently, it is unclear what the contribution of peacekeepers really is in this complex process.  Not only do belligerents have to give up arms with the risk of being annihilated by the other party that is not disarming (i.e. the government), they also need to commit to not going back to violence or defecting once disarmament and reintegration occurred. These are two separate commitment problems, and it is unclear which one peacekeepers can influence. It is possible that they solve both.  But this ambiguity lingers, and while it does not threaten the validity of the general argument put forward by the authors, it has consequences when we attribute the capacity to solve commitment problems to military units only.  Indeed, while providing reassurance that the other party will not take advantage of its superiority after DDR relies more on the missions’ military capacity, ensuring that parties stay committed to the peace process and have incentives to work together likely requires a political solution.

Showing how exactly peacekeepers solve the commitment problem and reduce information asymmetries that fuel conflict is a daunting task.  Lisa Hultman, Jacob Kathman, and Megan Shannon provide convincing, solid evidence that UN military forces can mitigate violence, and illustrate how the five activities might have played a role in two recent peace missions.  They do not claim to provide an exhaustive list of activities, and future research should evaluate research designs that allow a direct assessment of these (and potentially other) peace-promoting activities.  Recent work goes in this direction, and shows how missions’ reconciliation activities (mostly implemented by civilian, not military personnel) can suppress conflict locally.[16] Although previous research had already provided some indications that peacekeeping can contribute to peace,[17] Hultman, Kathman, and Shannon strike the right balance in concluding that not all missions are successful; on average they are, but some missions are more effective than others, and this is largely a function of their military capacity. In the last chapter of the book, the authors engage in a discussion of the ‘failures’ of peacekeeping, for example in relation to sexual abuse and exploitation or the economic distortions resulting from the so-called peacekeeping economies.  These issues are not just collateral effects, and the UN should address them with urgency by ensuring proper accountability systems (in line with the commitments expressed by UN members in the Action4Peacekeeping initiative).  However, the main message of Peacekeeping in the Midst of War should not be understated: because (under the right conditions) peacekeeping both works and saves lives, it is a key multilateral tool to tackle conflict.  This is even more important at a time when UN missions face financial constraints that can significantly reduce their capacity to authorize sizeable military deployments.



Review by Abiodun Williams, The Fletcher School of Law and Diplomacy, Tufts University

Peacekeeping, which famously is not mentioned in the Charter of the United Nations, is now over 70 years old and has shown remarkable flexibility and endurance.  Peacekeepers have monitored ceasefires, delivered humanitarian aid, advised on police reform, enforced peace agreements, organized elections, and protected civilians, among many other tasks.[18]  As the Cold War drew to a close and the international climate improved, the Norwegian Nobel Committee awarded the 1988 Nobel Peace Prize to UN peacekeeping forces.  Nonetheless, peacekeeping’s worth and relevance remain the subject of regular debate.  Despite media commentary to the contrary, the UN’s record in peacekeeping has been mixed, not disastrous.  A main goal of Lisa Hultman, Jacob Kathman, and Megan Shannon in this theoretically sophisticated and empirically rich book is “to address the disconnect between the empirical record of UN peacekeeping and the popular perception of peacekeeping” (21).  This will strike a chord with all those who are concerned about the erosion of faith in the potential of the UN to act in the interest of the global collective good.

A widely held view is that the UN can keep the peace when the weather is relatively fine, but it cannot do so in a storm.  This perception has its origins in the 1990s when UN peacekeepers were sent into places like Somalia, Bosnia, and Rwanda where there was no peace to keep, and without sufficient resources or a clear mandate.  The conflicts of the last decade of the twentieth century were also largely intra-state, and challenged the traditional practice of UN peacekeeping, which was predicated on there being a peace to keep.  Those difficult missions were flawed in conception and execution.  The response to the failures of the 1990s was soul-searching by the UN, resulting in reviews of what had gone wrong, and forward-leaning recommendations to remedy the deficiencies of peacekeeping given contemporary trends in conflict.[19]  The authors maintain that over the years a body of literature has appeared that evaluates peacekeeping missions in absolutist terms as either achieving “success” or suffering “failure.”  This absolutist approach obscures important variations in the performance of peacekeeping missions and sets lofty standards that are difficult, if not impossible, to meet.[20]

The volume is part of the latest and growing literature on peacekeeping that combines rigorous qualitative and quantitative analysis of peacekeeping effectiveness.  The recent literature takes a more nuanced approach to evaluating the overall impact of peacekeeping.[21]  The authors provide some encouraging news about UN peacekeeping.  Peacekeeping is effective in reducing violence in civil conflicts, which is a precondition for the accomplishment of other goals.  The book describes the several violence-reduction mechanisms employed by peacekeeping missions including separating combatants, creating buffer zones, assisting in the disarmament, demobilization, and reintegration of combatants, verifying compliance with peace processes, and policing in local communities behind the frontlines.  It argues convincingly that the capacity of a mission (deployment size) and its constitution (type of personnel) are two essential characteristics that enable peacekeeping to mitigate violence.  But it glosses over another key to effective peacekeeping, which is not so much who participates but how they participate.

It is evident that the UN typically takes on the hardest cases, as shown in the illuminating explorations of its peace operations in Côte d’Ivoire (the United Nations Operation in Côte d’Ivoire, UNOCI) and the Democratic Republic of the Congo (the United Nations Organization Stabilization Mission in the Democratic Republic of the Congo, MONUC and MONUSCO).  The Organization remains the actor of last resort when all other avenues are exhausted.  And given this reality, the UN’s record of success is striking, as the authors make clear: “Despite violent crises occurring on the UN’s watch in the two cases assessed…we still observe successful violence mitigation, particularly when the capacity of missions is enhanced” (167).  In a world of power politics and hashtag activism, it is inevitable that some crises garner more attention than others, but without the UN, such imbalances would be far more egregious.  Even where the Organization has faced setbacks, it is important to remember former UN Secretary-General Dag Hammarskjöld’s dictum that “the United Nations was not created in order to bring us to heaven, but in order to save us from hell,” the epigraph of the book’s opening chapter (1).  If that is the standard by which we judge the UN’s record, its success rate begins to look rather more impressive.

The authors do not have an idealized view of the UN and the findings of the book are not all rosy because “in reality, peacekeeping missions have a mix of positive and negative effects on conflict and political phenomena in the host state” (28).  The book underlines detrimental aspects of peacekeeping including its negative effects on the economies of host states, and sexual abuses committed by peacekeepers against civilians in their host country, as recent revelations have made clear.[22]  Establishing genuine accountability for abuses by peacekeepers is an improvement which still needs to be made to peacekeeping.

The book’s main recommendation, that peacekeeping missions should be designed with “larger numbers of armed troops and police” to reduce civil war violence, is hard to dispute (173).  But the basic problem which bedevils peacekeeping and remains to be addressed is a practical and political one:  the reluctance of member states to swiftly provide resources of the right quantity and quality to enable the UN to do its job properly.  Providing an answer to this pressing problem will make a real difference to how peacekeeping missions are carried out and – as important today – how the world perceives that they are being carried out.

Peacekeeping is an imperfect instrument that will remain vulnerable to misconceptions and unrealistic expectations.  Peacekeeping in the Midst of War is an important contribution to our understanding of peacekeeping’s limitations and its strengths.  In the words of former UN Secretary-General Kofi Annan which conclude the book: “we cannot say that peacekeeping will prevent all future wars, but we maintain that it can help humanity make its future less scarred by war than its past” (191).



Response by Lisa Hultman, Uppsala University, Jacob D. Kathman, SUNY Buffalo, and Megan Shannon, University of Colorado Boulder

We are humbled to have a wonderful group of scholars read and comment on our book.  Alex Bellamy’s work on peacekeeping and the Responsibility to Protect Doctrine is foundational to our research.[23] Without his vast work in this area, our collective understanding of peacekeeping and civilian protection would be far less rich.  Jessica Di Salvatore’s research on peacekeeping’s effect on criminal and ethnic violence and nonviolent protest is inspiring, as it has pushed peacekeeping research in important new directions, and has revealed both the promise and limitations of peacekeeping efforts.[24] And it is a real treat to receive a review from Abiodun Williams, whose eminent career in United Nations scholarship and peacekeeping practice offers a rare boundary-spanning perspective on our research.[25] We are grateful that such an illustrious group has given their time and energy to review our book, so we thank them and the ISSF/H-Diplo team for coordinating this on our behalf.

We are pleased by the generally positive response to the book and its contribution to the literature, but we note that important questions remain.  While it is not possible to respond to all of the points made by the contributors, we will speak to several general issues that these reviews raise. A thread woven throughout this response is the ever-growing literature on peacekeeping effectiveness.  Gaps left by our research are addressed in ongoing work by others.  Collectively, scholars are pushing the literature forward in new and interesting directions.

First, to reiterate one of the book’s central claims: peacekeeping effectiveness is best viewed on a continuum, rather than an absolute classification of ‘success’ and ‘failure.’ Our book relies on measures of peacekeeping effectiveness where missions are considered more effective if they reduce combat violence and violence against civilians.  This is perhaps the first and best indicator of effectiveness, given the UN’s propensity to deploy missions to active conflict environments and the centrality of violence reduction for achieving other objectives.  We claim that peacekeeping operations (PKOs) outfitted with increasingly large personnel deployments are better able to resolve information asymmetries and commitment problems between combatant factions through such activities as combatant separation, information sharing, disarmament/demobilization/reintegration (DDR) of combatant soldiers, and improving security behind the frontlines.  Both armed troop and police forces engage in these types of activities, informing the theoretical expectation that larger troop deployments reduce battlefield violence and troop and police commitments reduce violence against civilians.  This should not be taken as support for more robust peacekeeping.  The mechanisms we suggest are not based on the offensive use of force, only on the sufficient capacity and composition to carry out crucial security-related tasks.  The empirical analyses support the theoretical expectations, and show that larger and appropriately constituted missions effectively reduce violence.  This is evidence that the violence-reducing activities of peacekeeping missions are more fully employed as deployments increase in size.

However, as Di Salvatore points out, we do not reveal which particular mechanism is operating to reduce violence at a given time, much less the substantive consequence of individual mechanisms in reducing deaths. Tracing a reduction in violence to the use of specific peacekeeping mechanisms has important policy implications.  Unfortunately, there are impediments to teasing out each mechanism’s effect on violence.  For one, the functions performed by PKOs are determined by their mandates, which are determined by political processes on the UN Security Council (UNSC).  As such, the activities in which operations engage and the associated punishments or rewards that PKOs can dispense are the product of mandates the operations receive from the UNSC.  There is a great deal of overlap in operational mandates, and teasing out the mechanisms in a large-n statistical framework may prove challenging.  Further, actions may be circumstantially implemented as a product of mission decision-making on the ground.  For instance, as we point out in the book, civilian protection mandates are often teamed with language that permits circumvention when threats to personnel are dire or operational capacities are perceived as insufficient to the task.  As such, different mechanisms may be more or less operative at different times during deployments, even when a mission is consistently mandated to engage in those tasks. It is therefore difficult to locate the specific substantive consequence of each mechanism.  Still, recent research makes important progress, and deeper case analyses may be revelatory in this regard.[26] Scholars might also identify scenarios where certain mechanisms are more likely to be used effectively, such as situations where it is more feasible to separate combatants.  In policy terms, a fuller understanding of peacekeeping activities, or combinations thereof, that are most effective in violence reduction is a critical element of calibrating missions to achieving mission objectives.  Our work offers evidence that larger mission deployments better pursue mechanisms of violence reduction, but more work needs to be done to identify which mechanisms work best in violent situations.

The discussion of mechanisms is linked to an additional concern raised by Di Salvatore with regard to whether the UN has a “security first” orientation. We argue in the book that reducing violence and improving host state stability is a primary goal of peacekeeping.  Other mission objectives, including security sector reform, democratization, and economic recovery, are downstream from violence diminution.  Yet as Di Salvatore points out, the UNSC may not necessarily equip PKOs with the personnel capacity and composition necessary for improving security as a first-order condition.  Instead, personnel deployments may be more the product of political calculations rather than security concerns.  We agree on this point, and this could have received more discussion in the book.  Indeed, operations may be ineffective because of the garbage-can nature of mandate inclusion, the lack of prioritization between different mandated tasks, and the inability of operations to leverage deployment capacities to pursue first-order security goals.  The UN operation in Syria (UNSMIS) is an example.  While UNSMIS sought to achieve such goals as convincing the combatant parties to “stop the fighting,” “protect civilians,” and “stabilize the country,” the operation was never equipped to engage in activities that could support those ends, since political negotiations within the UNSC produced a small, feeble observer deployment to Syria that lasted only four months.[27]

As suggested in Williams’s review, motivating substantial deployments from the UN’s membership is a crucial element of effective peacekeeping, but achieving larger deployments is a multifold challenge.  As we have mentioned, authorizing sufficient deployment levels can be a politically charged process in the UNSC.  An additional challenge is inducing member-states to contribute enough personnel to satisfy UNSC mandates, and maintain them under difficult circumstances.  Important research has begun to uncover how to work under a politically charged process to best equip peacekeeping missions.[28] And future work on peacekeeping effectiveness is likely to benefit from an understanding of what motivates substantial personnel commitments as a first step to violence reduction.

To conclude, we reiterate the need to move away from simple binary conceptions of success and failure in peacekeeping.  Peacekeeping is complex, and the environments in which peacekeeping operates are dangerous and complicated.  In the book, we addressed but one dimension of such multifaceted processes: lethal violence.  Yet there is an open door to discussion of the additional ways to conceptualize effectiveness and how we might balance the ‘benefits’ of peacekeeping against the detriments that peacekeeping operations can foist upon their hosts populations.  As Bellamy points out in his review, one possible consequence of deploying larger PKOs is that acts of sexual violence perpetuated by peacekeepers may increase against people in their areas of deployment.  Further, peacekeeping economies, and the economic recessions they can induce, may be more economically damaging according to the size of the withdrawing PKO.  However, these negative effects of peacekeeping can be avoided.  While we do not engage in any direct analyses that compare levels of sexual exploitation or economic performance in the book, we do suggest that violence reduction may be one way of reducing opportunities for sexual predation and improving economic growth.  Additionally, increasingly large operations need not lead to increased malicious behavior by peacekeepers, as institutional and policy reforms can be leveraged to benefit local populations in the areas to which peacekeepers deploy.[29] As such, the detriments of the UN’s operational efforts need not be deterministically (nor even positively) correlated with the size of operations deployed.  A rapidly growing literature is sure to improve our understanding of how to reduce the negative externalities of peacekeeping.[30]



Beber, Bernd, Michael J. Gilligan, Jenny Guardado, and Sabrina Karim.  2019. “The Promise and Peril of Peacekeeping Economies.” International Studies Quarterly 63(2): 364-375.

Belgioioso, Margherita, Jessica Di Salvatore, and Jonathan Pinckney. 2020. “Tangled Up In Blue: The Effect of UN Peacekeeping on Nonviolent Protests in Post-Civil War Countries.” Forthcoming in International Studies Quarterly.

Bellamy, Alex J. 2014.  Responsibility to Protect: A Defense.  Oxford, UK: Oxford University Press.

Bellamy, Alex J., Paul D. Williams, and Stuart Griffin.  2010. Understanding Peacekeeping.  Cambridge, UK: Polity Press.

Bove, Vincenzo, Chiara Ruffa, and Andrea Ruggeri. 2020. Composing Peace: Mission Composition in UN Peacekeeping.  Oxford UK: Oxford University Press.

Bove, Vincenzo, Chiara Ruffa, and Andrea Ruggeri.  “How Does the Composition of Peacekeeping Operations Matter?” in Han Dorussen (ed.) Handbook on Peacekeeping and International Relations.  Cheltenham, UK: Edward Elgar Publishing.

Di Salvatore, Jessica.  2018. “Obstacle to Peace?  Ethnic Geography and Effectiveness of Peacekeeping.” British Journal of Political Science 50(3): 108-1109.

Di Salvatore, Jessica.  2019. “Peacekeepers against Criminal Violence – Unintended Effects of Peacekeeping Operations?” American Journal of Political Science 63(4): 840-858.

Lise Morjé Howard.  2019. Power in Peacekeeping.  Cambridge, MA: Cambridge University Press.

Kathman, Jacob D. and Molly Melin.  2017. “Who Keeps the Peace?  Understanding State Contributions to UN Peacekeeping Operations.” International Studies Quarterly 61(1): 150-162.

Karim, Sabrina and Kyle Beardsley.  2017. Equal Opportunity Peacekeeping: Women, Peace, and Security in Post-Conflict States.  Oxford, UK: Oxford University Press.

Passmore, Timothy JA, Megan Shannon, and Andrew Hart.  2018. “Rallying the Troops: Collective Action and Self-Interest in UN Peacekeeping Contributions.” Journal of Peace Research 55:3 (2018):366-379.

Smidt, Hannah M. 2020.  “United Nations Peacekeeping Locally: Enabling Conflict Resolution, Reducing Communal Violence.” Journal of Conflict Resolution 64(2): 344–372.

United Nations Security Council.  2012. Statement by the President of the Security Council.  S/PRST/2012/6, March 21.

Williams, Abiodun.  2017. “The Responsibility to Protect and Institutional Change.” Global Governance 23(4): 537-544.

Williams, Abiodun.  2000. Preventing War: The United Nations and Macedonia.  Lanham, MD: Rowman and Littlefield.

[1] Lisa Hultman, Jacob Kathman, Megan Shannon, “United Nations Peacekeeping and Civilian Protection in Civil War,” American Journal of Political Science, 57:4 (2013): 875–891.  Lisa Hultman, Jacob Kathman, Megan Shannon, ‘Beyond Keeping Peace: United Nations Effectiveness in the Midst of Fighting,” American Political Science Review 108:4 (2014): 737-753.

[2] Barbara Walter, Lise Howard, V. Page Fortna, “The Extraordinary Relationship between Peacekeeping and Peace,” British Journal of Political Science, first view, November 2020: 1-18.

[3] Nor are new missions starting—the UN has not fielded a new, large deployment since 2014.

[4] OSCE Special Monitoring Mission to Ukraine, September 2020 status report.

[5] Virginia Page Fortna, Does Peacekeeping Work?  Shaping Belligerents’ Choices after Civil War (Princeton: Princeton University Press, 2008) and Lise M. Howard, Power in Peacekeeping (Cambridge: Cambridge University Press, 2019).

[6] For example, Lisa Hultman, Jacob Kathman, Megan Shannon, “United Nations Peacekeeping and Civilian Protection in Civil War,” American Journal of Political Science 57:4 (2013): 875–891 and Lisa Hultman, Jacob Kathman, Megan Shannon, ‘Beyond Keeping Peace: United Nations Effectiveness in the Midst of Fighting,” American Political Science Review 108:4 (2014): 737-53.

[7] Respectively, Vincenzo Bove, Chiara Ruffa, and Andrea Ruggeri, Composing Peace: Mission Composition in UN Peacekeeping (Oxford: Oxford University Press, 2020) and Severine Autesserre, The Frontlines of Peace: An Insider’s Guide to Changing the World (Cambridge: Cambridge University Press, 2021).

[8] On ‘after exit’ see

[9] Robert Blair, Jessica Di Salvatore, and Hannah Smidt, “When Do UN Peacekeeping Operations Implement Their Mandates?” (2020) SSRN Electronic Journal.

[10] Andrea Ruggeri, Theodora-Ismene Gizelis, and Han Dorussen. (2013). “Managing Mistrust An Analysis of Cooperation with UN Peacekeeping in Africa,” Journal of Conflict Resolution 57:3 (2013): 387–409.

[11] See, for example, Michael Doyle and  Nicholas Sambanis, Making War and Building Peace: United Nations Peace Operations (Princeton: Princeton University Press, 2006); Virginia Page Fortna, Does Peacekeeping Work? Shaping Belligerants’ Choice After Civil War. (Princeton: Princeton University Press, 2008); Michael J. Gilligan and Ernest J. Sergenti, “Do UN Interventions Cause Peace? Using Matching to Improve Causal Inference,” Quarterly Journal of Political Science 3:2 (2008): 89–122.

[12] Lisa Hultman, Jacob Kathman, and Megan Shannon, “United Nations Peacekeeping and Civilian Protection in Civil War,” American Journal of Political Science 57:4 (2013): 875-891; Hultman, Kathman, and Shannon, “Beyond Keeping Peace: United Nations Effectiveness in the Midst of Fighting,” American Political Science Review (2013): 737-753; Hultman, Kathman, and Shannon, “United Nations Peacekeeping Dynamics and the Duration of Post-Civil Conflict Peace,” Conflict Management and Peace Science 33:3 (2016): 231-249.

[13] For a review of this quantitative research, see Di Salvatore and Andrea Ruggeri “Effectiveness of Peacekeeping Operations,” in William Thompson, ed., Oxford Research Encyclopedia of Politics (Oxford: Oxford University Press, 2107).

[14] Lise Morjé Howard, Power in Peacekeeping (Cambridge: Cambridge University Press, 2019).

[15] In fact, when separating combatants becomes unfeasible, belligerents may be less likely to respond to UN deployments with decreasing violence against civilians.  See Di Salvatore, “Obstacle to Peace? Ethnic Geography and Effectiveness of Peacekeeping,” British Journal of Political Science 50:3 (2020): 1089–1109.

[16] Hannah Smidt, “Mitigating Election Violence Locally: UN Peacekeepers’ Election-education Campaigns in Côte d’Ivoire,” Journal of Peace Research 57:1 (2020): 199–216.

[17] Fortna, Does Peacekeeping Work? Shaping Belligerants’ Choice After Civil War (Princeton: Princeton University Press, 2008); Michael Doyle and Nicholas Sambanis, Making War and Building Peace: United Nations Peace Operations (Princeton: Princeton University Press, 2006).

[18] See Alex J. Bellamy and Paul D. Williams with Stuart Griffin, Understanding Peacekeeping, 2nd ed. (Cambridge: Polity Press, 2010), 71-152.

[19] “Report of the Panel on United Nations Peace Operations,” A-55/305-S/2000/809, August 21, 2000; and “Report of the High-Level Independent Panel on Peace Operations, Uniting our Strengths for Peace: Politics, Partnership and People,” A/70/95-S/2015/446.  June 16, 2015.

[20] See, for example, Dennis C. Jett, Why Peacekeeping Fails (New York: St Martin’s Press, 1999), and Frederick H. Fleitz, Peacekeeping Fiascoes of the 1990s (Westport: Praeger, 2002).

[21] Two illuminating studies are Michael W. Doyle and Nicholas Sambanis, Making War and Building Peace:  United Nations Peace Operations (Princeton: Princeton University Press, 2006); and Lise M. Howard, UN Peacekeeping in Civil Wars (Cambridge: Cambridge University Press, 2008).

[22] News Articles | Preventing Sexual Exploitation and Abuse (,

[23] In particular, see Alex J. Bellamy and Paul D. Williams, with Stuart Griffin. Understanding Peacekeeping, 2nd ed. (Cambridge: Polity Press, 2010); Bellamy.  The Responsibility to Protect: A Defense (Oxford: Oxford University Press, 2015).

[24] Jessica Di Salvatore.  “Obstacle to Peace?  Ethnic Geography and Effectiveness of Peacekeeping.” British Journal of Political Science 50:3 (2018): 108-1109; Di Salvatore.  “Peacekeepers against Criminal Violence – Unintended Effects of Peacekeeping Operations?” American Journal of Political Science 63:4 (2019): 840-858; Margherita Belgioioso, Di Salvatore, and Jonathan Pinckney.  “Tangled Up In Blue: The Effect of UN Peacekeeping on Nonviolent Protests in Post-Civil War Countries,” International Studies Quarterly, forthcoming.

[25] See Williams’s work on conflict prevention and the Responsibility to Protect doctrine, including Abiodun Williams.  “The Responsibility to Protect and Institutional Change,” Global Governance 23(2017): 537-544; Williams.  Preventing War: The United Nations and Macedonia (Lanham: Rowman and Littlefield, 2000).

[26] Lise Morjé Howard, Power in Peacekeeping. (Cambridge: Cambridge University Press, 2019); Hannah M. Smidt. “United Nations Peacekeeping Locally: Enabling Conflict Resolution, Reducing Communal Violence.” Journal of Conflict Resolution 64:2 (2020): 344–72.

[27] United Nations Security Council.  2012. Statement by the President of the Security Council.  S/PRST/2012/6, March 21.

[28] On shortfalls in peacekeeping personnel contributions, see Timothy JA Passmore, Megan Shannon, and Andrew Hart, “Rallying the Troops: Collective Action and Self-Interest in UN Peacekeeping Contributions.” Journal of Peace Research 55:3 (2018):366-379.  See also Vincenzo Bove, Chiara Ruffa, and Andrea Ruggeri, Composing Peace: Mission Composition in UN Peacekeeping (Oxford: Oxford University Press, 2020).  On the domestic and geopolitical security implications of peacekeeping personnel contributions by UN member states, see Jacob D. Kathman and Molly Melin.  “Who Keeps the Peace?  Understanding State Contributions to UN Peacekeeping Operations,” International Studies Quarterly 61:1 (2017): 150-162.  For a review of the importance of mission composition for operational effectiveness, see Bove, Ruffa, and Andrea Ruggeri, “How Does the Composition of Peacekeeping Operations Matter?” in Han Dorussen, ed., Handbook on Peacekeeping and International Relations (Cheltenham, UK: Edward Elgar Publishing).

[29] For instance, improving the UN’s ability to report and punish sexual abuses by its peacekeepers, improving gender balancing of operations, and expanding peacekeeper training and professionalism can reduce sexual exploitation.  More extensive economic planning that carefully considers issues of improving economic growth and sustainability during PKO deployments and following their withdrawal can also help reduce the ill-effects of peacekeeping economies.

[30] For examples, see work by Sabrina Karim and Kyle Beardsley.  Equal Opportunity Peacekeeping: Women, Peace, and Security in Post-Conflict States.  (Oxford: Oxford University Press 2017); Bernd Beber, Michael J Gilligan, Jenny Guardado, and Sabrina Karim.  “The Promise and Peril of Peacekeeping Economies.” International Studies Quarterly 63:2 (2019):364-379.