The making of international law through multilateral conventions and adjudication often leads to periods of legal uncertainty, times in which there are alternative rules and divergent views on how they ought to be applied to particular cases. I argue that legal uncertainty gives states opportunities and incentives to formulate excessive unilateral claims, thus making disputes more likely to arise.

This study presents new theory and evidence on the repertoire of electoral intimidation, suggesting that threats can be used to deter rival party supporters from voting but also to mobilize citizens to vote for a particular party. We expect these strategies to unfold in the same electoral context, but differ in targeting and incidence; while threats to demobilize are concentrated in closely contested

Why are some autocratic regimes more prone to mass uprisings than others? This article argues that autocratic leaders can mitigate opposition mobilization by strategically appointing opposition leaders to cabinet positions. Drawing on yearly data from autocracies between 1966 and 2020, the article exploits temporal variations in the composition of cabinets and the onset of mass uprisings within autocratic

This paper presents a game-theoretic model where dissidents with heterogeneous abilities and motivations contribute to collective action. A regime demotivates dissidents by preemptively increasing their costs of contributing, using a budget that can be spread across them in any way desired. The regime’s optimal targeting strategy is shown to depend on the (technological) degree of complementarity between

There is ample evidence that the political exclusion of minorities from state power increases the risk of conflict. Nevertheless, do these same results apply to local representation? I explore this question using the success in mayoral elections of the Chilean Mapuche, a deprived indigenous minority in a longstanding conflict against the Chilean state. Combining a novel database on conflict and a surname

Under what conditions do sponsors directly intervene in the target state’s civil conflicts? While previous research on state sponsorship for the rebels tends to focus on how ties between the two can influence their interactions, this article argues that the sponsor is more willing to provide combat support when the target state is under the rule of a personalist regime. Due to a lack of internal constraints

There is a scarcity of systematic data regarding the military equipment of rebel groups engaged in intrastate conflicts. This empirical gap has impeded the rigorous evaluation of (formal) theories concerning militarized interactions between governments and rebel groups. To address this deficiency, we have developed the Rebels' Armament Dataset (RAD). This dataset provides detailed information on the

This paper analyses how pre-pandemic levels of inequality across US counties have shaped the impact of the COVID-19 pandemic on the incidence of protests. The results from difference-in-differences and instrumental variable models using high-frequency weekly data show that more stringent measures to contain the pandemic increased the incidence of protests, but only in US counties with high levels of

Are civil wars shaped by how they start? While existing literature points to the path-dependent nature of conflict, the link between the type of onset and wartime dynamics have been largely overlooked. Building on a recent typology capturing the dynamics of civil war onset (1944–2020), I analyze conflict trajectories, focusing on three macro-level wartime dynamics: warfare, intensity, and duration

This paper is concerned with state capacity and autocrat survival. We argue that state strength in autocracies increases leader tenure but reduces the stability of the regime itself; stronger autocracies run a higher risk of transitioning to democracy. This trade-off arises as a result of how state capacity affects the behavior of elite challengers. A stronger state reduces the likelihood of the ruler

In this study, we experimentally test the theoretical results of a contest game between groups when the value of the prize is fixed and when it is endogenously determined. It can decrease with contest efforts of all groups as in the case of an armed conflict or a lawsuit. The value of the prize can also increase with contest efforts as in the case of a patent race. We also analyze the impact of different

The militarization of border control is a defining feature of contemporary international politics. Why do states flock toward these policies despite their questionable efficacy? We theorize that border militarization stems in part from public reactions to the threat of international and domestic decline. We test this argument with two conjoint experiments that randomize the implementing agency, strategy

This article introduces the US Aid to Security Sector Actors (USASSA) dataset, the product of a collaboration between academic researchers and the nonprofit Security Assistance Monitor. In addition to providing the most comprehensive source of data on US security assistance, the USASSA dataset transforms detailed information about how security assistance funds are spent into aid and recipient typologies

The existing literature on terrorism focuses on the “rally-around-the-flag-effect” – a relatively short-term phenomenon. The non-immediate effects of terrorist attacks on trust in institutions, however, remain largely unexplored. Arguing that maintaining law and order and upholding peace is considered the responsibility of the political and legal institutions in democracies, we theorize the “accountability

Empirical studies have shown that terrorists’ policy goals are rarely achieved, leading some to conclude that terrorism doesn’t work. We theorize that terrorism can work, but for its supporters rather than for the terrorists themselves. Because supporters are willing to contribute resources to a terrorist organization, thereby increasing the organization’s ability to launch attacks, this can coerce

When and why do foreign policy officials believe that it is important to fight for credibility? Conventional wisdom suggests that policymakers tend to care uniformly about how others perceive them. Yet this logic overlooks substantial variation in how officials prioritize credibility when weighing policy options. I argue that organizational identity affects the dimensions of credibility that policymakers

International courts lack traditional enforcement mechanisms. Scholars theorize that compliance with human rights rulings is therefore often driven by domestic processes, including political mobilization and parliamentary agenda setting. A necessary condition underlying these processes is attention to the rulings which is in part expected to be mediated by media attention. However, these conditions

States often intentionally stall crisis negotiations, hoping to build arms or attract allies to achieve a more favorable bargaining position. Why do their adversaries tolerate delay in some cases, but attack upon delay in others? I argue that this is because states cannot perfectly distinguish between intentional and unavoidable delays. This presents a strategic tension: a state prefers to attack preventively

This article explores the phenomenon of high levels of public trust in the military across the Global South. We extend arguments from the US civil-military relations literature to a broader context and generate testable hypotheses to explain trust in the armed forces driven by the military’s performance and professionalism, and the public’s patriotism and partisanship. Using public opinion survey data

How is service history associated with returning veterans' attitudes about democracy? Existing research predicts pro-government militia veterans have less support for democracy because of political efficacy gained from service and divergent policy preferences from the general population. We test that theory in Ukraine through surveys of both returning veterans and the general population between 2019

Though previous research has recognized that armed groups do not always recruit fighters on a voluntary basis, varieties and determinants of insurgent forced recruitment are still poorly understood. What drives armed groups to employ certain methods of coercive recruitment? This article conceptualizes and studies a particular form of coerced recruitment—insurgent conscription—whereby rebel groups rely

Following regime change, how does wartime victimization shape political attitudes and participation in the long run? I argue that it increases post-war political vigilance: greater sensitivity to illiberal politics and poor governance, but with dampened effects on participation under authoritarianism due to greater fear of harm. I examine Protected Villages (PVs) in the Zimbabwe Liberation War (1972–1979)

Why do some individuals with military experience support the insurrection of January 6? With US military veterans playing a central role in the assault on the US Capitol, answering this question is of immediate scholarly and policy concern. To better understand the impact of military service, we conducted the first nationally representative survey of support for pro-Trump anti-democratic violence (“insurrectionist

Autocratic elections are often marred with systematic intimidation and violence towards voters and candidates. When do authoritarian regimes resort to violent electoral strategies? I argue that electoral violence acts as a risk-management strategy in competitive authoritarian elections where: (a) the regime’s prospects for coopting local elites, competitors, and voters are weak, and (b) the expected

We investigate the impact of UN peacekeeping on voluntary returns and negative attitudes towards displaced persons. We posit that peacekeeping missions can have beneficial effects by improving security and alleviating the socio-economic burden imposed by new arrivals on receiving communities. Focusing on the critical case of South Sudan, we combine information on peacekeepers' subnational deployment

How can one increase openness towards conflict refugees in states that have experienced conflict? While highlighting shared war experience may reduce hostility toward refugees by enabling people to better understand the plight of refugees, it may also foment higher levels of out-group antipathy due to heightened feelings of threat. To answer this question, we leverage the context of South Korea, a

Millions of people around the world are internally displaced. And yet – compared to other forms of wartime victimization – scholars know relatively little about the long-run consequences of displacement for victims. This gap in the literature is problematic since displacement is distinct from other forms of victimization, and because IDPs face unique challenges in post-conflict transitions. This study

How does conflict, displacement, and return shape trust, reconciliation, and community engagement? And what is the relative impact of exposure to violence on these indicators? In this paper we explore these questions by focusing on the legacies of armed conflict and the differences between those who stayed in their communities of origin during the conflict (stayees) and those who were displaced internally

This research highlights a neglected paradox of migration policies: whereas narratives on migrants as a security threat in their countries of destination find little support in empirical studies, forcing migrants to return may increase violence and crime back home. Using migrants’ exposure to deportation threats at destination as an exogenous source of identification, this paper traces the long shadow

Land reform has been employed as a component of counterinsurgency strategies to inoculate peasants against rebel appeals by giving peasants their own land. However, the remedial effects of land reform can be undermined by right wing violence and rebel violence intended to subvert land reform implementation. We used municipio level data on land reform and election results from El Salvador to test propositions

The global rise of right-wing populist (RWP) leaders has raised concerns about the threat they pose to a cooperative international order, but there is little systematic evidence linking RWP leaders to military aggression. Are RWP leaders more prone to initiating international disputes? If so, when and why? We argue that a RWP leader’s hyper-nationalist rhetoric can galvanize popular support for militant

Growing affective polarization, or animosity between competing ideological groups, threatens to tear apart democratic societies worldwide. In nations that are facing external conflicts, the threat arising from these conflicts may boost internal cohesion and potentially reduce the internal threat of fragmentation. However, in the current study, we analyze survey datasets from two societies embedded

I examine the effect of the policing capacity of traditional authorities (TAs) on communal conflict. TAs of ethnic groups use distinct customary laws and dispute-resolution mechanisms. Their coexistence with national norms and those of other TAs results in parallel legal systems. I argue that this generates uncertainties about norms and vertical and horizontal jurisdictional conflict, which increases

Military spending data measure key international relations concepts such as balancing, arms races, the distribution of power, and the severity of military burdens. Unfortunately, missing values and measurement error threaten the validity of existing findings. Addressing this challenge, we introduce the Global Military Spending Dataset (GMSD). GMSD collates new and existing expenditure variables from

Why do some rebel organizations form a united front when others confine themselves to a loose partnership? Existing research on rebel movements reveals that insurgents should quickly leave cooperative agreements if doing so will provide particular advantages in a post-conflict setting. Still, rebel groups may build diverse alliances, from joint attacks to shared command structures. If rebels are indeed

How does third-party diplomatic and material support affect rebel groups’ use of terrorism in civil wars? We argue via a game-theoretic model that diplomatic support prompts prospective shifts in rebel tactics, from civilian to military targets, in anticipation of material support, while material support alters the cost structure of attacks, leading to the same tactical shift. We empirically test the

A growing body of research argues that external threats from the international system strengthen ethnocentrism and authoritarianism, personal values anchored in national identity. We evaluate a necessary implication of this argument, that these shifting values drive change in broader social behaviors. Our focus is revealed value change in a non-political setting: American consumers’ choice of supermarket

Many European nation-states were historically homogenized through violent ethnic cleansing. Despite its historical importance, we lack systematic evidence of the conditions under which groups where targeted with cleansing and how it impacted states’ ethnic demography. Rising nationalism in the nineteenth century threatened multi-ethnic states with “right-sizing” through secessionism and irredentism

International weapons transfers send military capabilities, make arms production economically feasible, and construct security relations. They influence buyers’ and sellers’ foreign policies, domestic politics, and military spending behavior. However, data availability has limited their study to the bipolar Cold War and unipolar post-Cold War periods. We thus introduce the Interwar Period International

"Loyalty trials" are common to a range of conflict settings, with consequences that range from harassment to imprisonment, torture, or death. Yet, they have received little if any attention as a general phenomenon in studies of state repression, civil war, or rebel governance, which focus on particular behaviors that authorities use to put people on trial, such as dissent, defection, and resistance

We use this article to introduce the Militarized Interstate Confrontation (MIC) dataset, 1816-2014—a new dataset for international conflict with a host of innovative features. The MIC data corrects...

A purported advantage of secrecy in international politics is its ability to reduce pressures for conflict escalation by obscuring responsibility for hostile actions. Delegating these actions to pr...

The “rally 'round the flag” effect—a short-term boost in a political leader’s popularity during an interstate political dispute—was first proposed by Mueller (1970) more than half a century ago. Ho...

Does “shaming” work in NATO? More precisely, does publicly using negative language criticizing allies’ defense spending improve burden-sharing, or is it counterproductive, leading to lower spending...

A growing literature has documented widespread variation in the extent to which insurgents provide public goods, collect taxes, and regulate civilian conduct. This paper offers what is, to our know...

Defense policy makers have become increasingly concerned about conflict in the “gray zone” between peace and war. Such conflicts are often interpreted as cases of deterrence failures, as new techno...

What determines the outcomes of civil wars? Existing literature highlights numerous factors at the systemic, state, and organizational levels of analysis. Yet there is little research on the attrib...

Many of the world’s major cities have recently seen large episodes of social unrest. What is the relationship between the changes these cities have experienced, particularly in the form of gentrifi...

In dyadic ultimatum bargaining proposers, who are privately informed about the pie size, can exploit their “moral wiggle room” by engaging in unfairness which is unobservable by responders. Our set...

Existing research portrays militant splinter groups as more violent than their parent organizations due to factors like more extreme preferences or capacity-building needs. Though widely held, the ...

Studies have shown that intergroup conflict may result from two distinct human motives: the desire to obtain personal retributions from conflict (egoism), and the desire to sacrifice for the benefi...

Kidnapping is a common tactic used by insurgent groups. However, why insurgents commit kidnappings remains insufficiently understood. Based on 1,386 group-year observations of 140 insurgents betwee...

Terrorist designation has increasingly become an important counterterrorism tool used by intergovernmental organizations and state governments. This article examines the determinants of terrorist l...

Why did some American citizens choose to travel to fight in Syria and Iraq rather than engage in Islamic State of Iraq and Syria (ISIS)-inspired terrorism in the United States? We conducted a socia...

Do international naming and shaming campaigns reduce public support for repressive leaders? International advocacy can provide domestic audiences with new information about human rights abuses and ...

Ceasefires are a critical tool for those engaged in conflict management during civil wars, yet little scholarship exists that systematically assesses the durability of these arrangements. We argue ...

Pundits debate whether conflict in cyberspace is more likely to trigger or preempt conflict in other domains. We consider a third possibility. Rather than directly complementing or substituting for...

Quantitative research into the effectiveness of the UN human rights treaty bodies (UNTBs) in eliciting remedial responses from states is impeded by a lack of usable data on how states respond to th...