T. V. Paul’s edited volume and Yoram Haftel’s book bring regionalism back into international relations theory. Both authors ask why in some regions there is peace and even security communities while other regions remain trapped in enduring rivalries. In International Relations Theory and Regional Transformation, the contributors use a wide range of IR theories to explain regional transformations including realist, liberal, constructivist, and eclectic perspectives. Regional Economic Institutions and Conflict Mitigation primarily engages the liberal perspective. For Haftel, regional economic organizations (REOs) and especially their design and the implementation of agreements can have an important effect on the level of regional conflict and the success of conflict management mechanisms.

There are a number of similarities between these books. First, both Paul and Haftel address why interstate conflict has declined in some regions but not in others. Second, both move beyond explaining dyadic peace and address the more difficult problem of regional peacemaking. Third, both books advance policy-relevant, concrete findings for practitioners to improve regional conflict management mechanisms. Finally, Haftel’s book and some of the contributors to the edited volume are engaged in a growing discussion at the nexus of political economy and security studies, considering such topics as the relationship between trade and conflict, the security externalities of trade, the trade-off between defense spending and domestic investment, and the use of economic statecraft tools such as sanctions and incentives.

The ambitious and comprehensive edited volume is intended to push the study of regional orders forward, beyond its current atomized and narrow paradigmatic state. Paul accomplishes this by organizing the volume around the major IR approaches, allowing for a wide-ranging discussion of the role of power, institutions, regime type, economic interdependence, ideas, identity, and practices and their effect on regional stability, peace, and security communities. His intent is to capture the common variables or “meeting points” across these paradigms to account for regional transformation. One good example is the chapter by Norrin Ripsman, who builds on both realism and liberalism. Ripsman maintains that regional peacemaking should begin with a realist top-down approach at the government level. However, transforming negotiated agreements into entrenched partnerships requires the bottom-up mechanisms of economic interdependence, democratic regimes, or cooperative international institutions.

According to Paul’s introductory chapter, regional transformation entails “long term” and “meaningful” change in the relationship among states in a region. This broad definition allows for a big-tent conversation about why regional transformations occur. For Paul, in contrast to Haftel’s model, extraregional and great powers may be included in the regional security complex. Writing from realist perspectives, both Dale Copeland and Jeffrey Taliaferro emphasize the role of the great powers as triggers for regional transformation. For Copeland, great powers shape the power differentials and trends of the major regional actors to either moderate the likelihood of conflict or increase it. Taliaferro, who differentiates between extraregional states and pivotal states within particular regions, maintains that coordinated strategies can decrease the near-term likelihood of interstate conflict and facilitate regional transformation over the long term.

For Paul, positive regional transformation occurs along a continuum. The first stage in regional transformation is what he terms a regional system that is characterized by balance-of-power politics. The next stage is regional society where states recognize that they have common interests despite differences and disputes. The highest stage is regional community, which entails an unwillingness to consider the use of force among the members. In his introductory chapter, Paul raises several important questions related to this continuum. First, he asks what mechanism can transform regions. The contributors discuss the role of powerful triggers for regional transformation, such as the great powers, agents, and ideas. Second, the editor asks, but the contributors fail to answer in any systematic manner, the vital question of how to move a region from one stage to the next.

One shortcoming in this inclusive volume is whether realist, liberal, and constructivist theories that were developed to explain great power dynamics and especially the European model can explain regional transformations in other locales. Specifically, can these perspectives be taken off the shelf, slightly modified and adapted, and applied to conflict-ridden regions to account for progress (or the lack thereof) in regional transformations? Among the contributors, John Owen raises some doubt about applying the commercial peace literature to regions. While he is clear that the dyadic effect of economic interdependence is robust, he questions whether this dynamic can be reproduced at the regional level. Specifically, it is not sufficient for dyads to liberalize; to avoid intraregional conflict, the entire region must become interdependent. According to Owen, for this to occur, either hegemony or democracy will be required, both of which he argues can be problematic. Still, John Oneal in his chapter highlights the pacific effect of democracies and finds no evidence to support Jack Snyder and Edward Mansfield’s claim that democratizing states are more conflict prone.

Haftel’s book is a smart and methodologically sophisticated study of the effect of regional economic institutions on conflict reduction at the regional/subsystemic level. For this reason alone, students in IR theory should read this book carefully. Haftel uses a rationalist theory-of-war model or a bargaining model. The underlying argument is that interstate conflict is costly and occurs primarily due to some failure in the bargaining process, such as miscalculation, uncertainty, or indivisibility. For the author, the combination of effective institutional design of REOs and the implementation of negotiated agreements can reduce and even eliminate these causes of regional armed conflict.

Haftel develops a data set of 25 REOs from the 1980s and 1990s and puts it to good use. His main research question is why some REOs facilitate peacemaking and why the record of REOs in reducing interstate conflict is so mixed. For Haftel, three institutional design features of REOs matter in facilitating regional peacemaking. These are the scope of economic activity; the regularity of meetings of high-level officials to facilitate communication and to reduce miscalculation and uncertainty among regional states; and institutional autonomy in terms of the corporate bureaucracy and dispute-settlement mechanism (DSM), which foster peace through mediation, information, and adjudication. In addition to institutional design, the extent of the implementation of the negotiated agreements matter.

One crucial question that Haftel addresses in depth, and in a sophisticated manner that accepts some of the limitations of his argument, is that of causality and especially the problem of reverse causality. He demonstrates that the design and implementation of REOs affect interstate militarized disputes, rather than the reverse argument. He also addresses the problem that the relationship between regional institutions and regional peace might be spurious, caused by other variables such as the distribution of power, regime type, or interdependence. Given the original data set that he develops for the quantitative sections, one shortcoming is the Association of Southeast Asian Nations case study, which relies on secondary material to substantiate his argument.

Haftel does a good job of placing his argument in the context of the existing literature of scholars who work on some combination of REOs, institutions, interdependence, armed conflict, and conflict mitigation, including some of the contributors to Paul’s volume. Both the work of other scholars and Haftel’s contributions to the field are clear, especially where he advances the discussion.

Given the breath and scope of the topic of regional conflict-management mechanisms, there are holes in Haftel’s book. First, the author’s use of a rationalist bargaining model has its shortcomings. For him, the state is largely a black box. In his model there are high-level officials and bureaucrats in the REOs who are representatives of the government. These high-level officials are not members of the foreign policy executive (FPE) in the government—the inner circle, Kitchen Cabinet, ExComm, or Tuesday Lunch Group who are responsible for, and tasked with, making foreign economic and security policy, including the difficult choices related to peacemaking, conflict management, and armed conflict. Do these high-level officials who represent the REOs have influence on or access to the FPE, and does the FPE listen to them? Another neglected group is domestic and societal economic actors. The domestic political-economy model distinguishes between broad and logrolled coalitions of inward- and outward-oriented firms, sectors, or factors of production. These groups reflect the winners and losers from trade and cooperation and will lobby state leaders for their preferred policies, though they too remain outside of the model.

Second, Haftel’s book is about regional peacemaking. The reader is left wondering how REOs move member states through the different stages of peacemaking that are necessary for regional transformations. Specifically, how do REOs promote negotiations between rival states, facilitate the signing of peace agreements, assist in the implementation of the agreement, and move from dyadic peace to regional peacemaking? Both Haftel and Paul fail to systematically address this vital question.

Finally, the narrow focus on REOs, though important to better understand their independent effect on conflict management, ignores other significant actors in the international and regional system that contributes to regional peace and armed conflict. Moreover, these other groups interact with and have influence on the REOs. Specifically neglected are noneconomic organizations such as military or energy, third parties, and extraregional actors. The chapter by Stephanie Hofmann and Frederic Merand in the edited volume addresses this problem. The authors maintain that the presence of a dense web of institutions increases the opportunity cost of conflict.

Both books make important contributions to the literature on regional transformations and conflict management mechanisms, discussing why in some regions peace and even security communities emerge. In answering this question, Paul, sets as his goal to discover the common ground among atomized explanations, whereas Haftel’s goal is to emphasize the role of regional economic organizations and their design. With the decline of great power rivalries for now and the renewed focus on regionalism with the rise of the BRICS (Brazil, Russia, India, China, and South Africa) and the rest, these books offer a welcome opportunity for students, scholars, and practitioners to better understand how and why peacemaking has succeeded in some regions.