National Security

February 11, 2016
Eli Berman of University of California, San Diego, Organizer

Alex Imas, Carnegie Mellon University; Michael A. Kuhn, University of Oregon; and Vera Mironova, University of Maryland

A History of Violence: Field Evidence on Trauma, Discounting and Present Bias

The extent to which individuals discount the future and whether they discount in a time-consistent fashion is an important determinant of their life outcomes. Using a field experiment in the Democratic Republic of Congo, Imas, Kuhn, and Mironova show that direct exposure to violence substantially increases present bias — choice of the smaller, immediate reward over the larger, later reward. The researchers demonstrate that providing individuals with a delay between information about the choice and the choice itself mitigates the differences in behavior between those who were exposed to violence and those who were not. The authors' findings suggest that enforcing a cooling off period between income notification and consumption opportunities may help generate more patient choices and mitigate the elevated impulsivity of individuals that have experienced violence. The researchers measure their treatment effects both in reduced-form as well as in the form of structural estimates of a quasi-hyperbolic discounting function to enable comparison with measures of other types of time inconsistency and a welfare evaluation of the treatment effect. Their results have implications for policies aimed at alleviating the deleterious effects of present bias and the role of deliberation in the structure of commitment contracts.

Samuel A. Bazzi and Matthew Gudgeon, Boston University

Local Government Proliferation, Diversity, and Conflict

The creation of new local governments is a key feature of decentralization in developing countries. The implications of this process for violent conflict are not well understood. On the one hand, bringing representative government closer to the electorate can reduce heterogeneity in preferences, thereby mitigating conflict. On the other hand, creating local government institutions also leads to a large increase in rents that may be contested violently. Group cleavages can determine which of these two effects prevails. Identifying these distinct channels empirically has proven difficult. This paper resolves these challenges by exploiting a natural experiment in the ethnically and religiously diverse context of post-authoritarian Indonesia where rapid decentralization was accompanied by dramatic growth in the number of new districts and a resulting decline in ethnolinguistic fractionalization. Bazzi and Gudgeon use new microdata on conflict from 2000–2014 and leverage the plausibly exogenous timing of redistricting due to a government moratorium. Overall, redistricting has small and insignificant average effects on conflict. However, areas that experience greater ethnolinguistic and religious homogenization as a result of splitting experience a significant reduction in conflict. At the same time, the researchers find a differential increase in violence in areas that receive a new government and are also ethnically polarized. These differential increases in violence are most pronounced around the time of the first election and for types of violence associated with contestation of public resources and institutions. These results suggest that allowing for redistricting along group lines can reduce conflict, but the benefits of reduced diversity may be undone if the newly governed population is highly polarized. In such cases, conflict may then simply shift from the original seats of government to newly created ones.

Brian Duncan and Hani Mansour, University of Colorado Denver, and Bryson Rintala, U.S. Air Force Academy

Weighing the Military Option: The Effects of Wartime Conditions on Career Pathways

Joining the military to obtain training and educational benefits is an important option available to young Americans at the start of their careers. In this paper, Duncan, Mansour, and Rintala show that making the military option less desirable has lasting consequences on career paths. Using internal military data, they find that county-level exposure to U.S. combat casualties during the Iraq and Afghanistan Wars decreases the supply of new soldiers in that county. Moreover, the researchers find that casualties from a given county change the observable characteristics of soldiers who enlist in that county. Their identifying assumption is that the assignment of casualties to U.S. home of record counties is as-good-as random and that it does not impact military's local demand for soldiers, which is instead set at the national level. To investigate the schooling choices of youth as a function of wartime conditions, they use data from the American Community Survey. The findings indicate that exposure to casualties at a young age (17-18) increases the probability of dropping out from high school, and decreases the probability of attaining any college education. The results suggest that, at least for some youth, having the military option available motivates them to finish high school and serves as an important vehicle through which they can acquire post-secondary education.

Ryan Brown, University of Colorado, Denver; Verónica Montalva, Duke University; Duncan Thomas, Duke University and NBER; and Andrea P. Velásquez, University of Colorado, Denver

Impact of Violent Crime on Risk Aversion: Evidence from the Mexican Drug War

Whereas attitudes towards risk are thought to play a key role in many decisions over the life-course, factors that affect those attitudes are not well understood. This study investigates how risk attitudes are affected by elevated levels of insecurity and uncertainty brought on by an unanticipated increase in violent crime. Using longitudinal survey data on Mexican individuals collected before and during the recent dramatic increase in drug-related violence driven by the Mexican war on drugs, Brown, Montalva, Thomas, and Velásquez examine how attitudes towards risk are affected by local-area increases in crime. This study contributes to the current literature by pairing a plausibly exogenous change in conflict with models that account for individual- and location-specific time-invariant unobserved factors and shield the estimates from endogenous migration. The researchers' findings indicate that a rise in local-area violent crime results in increased risk aversion. These results suggest that a violent environment may adversely affect the long-term well-being of the exposed population through unexpected channels such as investment behavior and occupation choice.

Benjamin Crost, University of Illinois at Urbana-Champaign; Claire Duquennois, UC Berkeley; Joseph Felter, Stanford University; and Daniel I. Rees, University of Colorado at Denver

Climate Change, Agricultural Production and Civil Conflict: Evidence from the Philippines

Using unique data on conflict-related incidents in the Philippines, Crost, Duquennois, Felter, and Rees exploit seasonal variation in the relationship between rainfall and agricultural production to learn about the mechanism through which rainfall affects civil conflict. The researchers find that above-average rainfall in the dry season increases agricultural production and, with a one-year lag, dampens conflict intensity. In contrast, above-average rainfall in the wet season is harmful to crops and leads to more conflict the following year. Consistent with the hypothesis that rebel groups gain strength after a bad harvest, there is evidence that lagged rainfall affects the number of violent incidents initiated by insurgents but not the number of incidents initiated by government forces. These results suggest that the predicted shift towards wetter wet seasons and drier dry seasons will lead to more civil conflict even if annual rainfall totals remain stable. The authors conclude by noting that policies aimed at mitigating the effect of climate change on agriculture could have the added benefit of reducing civil conflict.

Mathieu Couttenier, HEC Lausanne; Veronica Preotu and Dominic Rohner, University of Lausanne; and Mathias Thoenig, Université de Lausanne

The Violent Legacy of Victimization: Post-Conflict Evidence on Asylum Seekers,Crimes and Public Policy in Switzerland

Couttenier, Preotu, Rohner, and Thoenig study empirically how past exposure to conflict in origin countries makes migrants more violent prone in their host country, focusing on asylum seekers in Switzerland. The researchers exploit a novel and unique dataset on all crimes reported in Switzerland by nationalities of perpetrators and victims over the period 2009-2012. Causal analysis relies on the fact that asylum seekers are exogenously allocated across the Swiss territory by the federal administration. Their baseline result is that cohorts exposed to civil conflicts/mass killings during childhood are on average 40 percent more prone to violent crimes than their co-nationals born after the conflict. The effect is stable through the lifecycle and is attenuated for women, for property crimes and for low-intensity conflicts. Further, a bilateral crime regression shows that conflict exposed cohorts have a higher propensity to target victims from their own nationality — a piece of evidence that the authors interpret as persistence in intra-national grievances. Last, the researchers exploit cross-region heterogeneity in public policies within Switzerland to document which integration policies are able to mitigate the detrimental effect of past conflict exposure on violent criminality. In particular, they find that offering labor market access to asylum seekers eliminates all the effect.

Vera Mironova, University of Maryland, and Samuel Whitt, Fulbright Scholar, University of Prishtina

Grievances in Civil War Participation: Micro-Level Evidence from Syria

Recent macro-level studies have revived interest in grievance-based explanations of civil war participation. Using original survey data from the ongoing conflict in Syria, Mironova, Whitt, and Mrie try to understand at the micro-level whether fighters, civilians, and refugees can be distinguished based on intensity of personal, social sectarian, and regime-based grievances. Using a well-balanced sample of over 300 active rebel fighters, civilians from within the conflict zone, and externally displaced refugees, the researchers observe that insurgents tend to have strongest regime-based grievances. In contrast, refugees and civilians are less revenge-seeking and more willing to support negotiations for peace and reconcile with regime supporters. Their results speak to the role of grievances in sustaining violence in civil war and to the challenges of securing peace. At the micro-level, grievances appear relevant to understanding not only mobilization for violence, but also conflict duration, the likelihood of negotiated settlements, and prospects for reconciliation.

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