Kevin Lewis

March 04, 2020

When Do Leaders Free‐Ride? Business Experience and Contributions to Collective Defense
Matthew Fuhrmann
American Journal of Political Science, forthcoming


The logic of free‐riding expects that individuals will underinvest in public goods, but people often behave in ways that are inconsistent with this prediction. Why do we observe variation in free‐riding behavior? This study addresses this question by examining contributions to an important international public good — collective defense in military alliances. It develops a behavioral theory of free‐riding in which the beliefs of world leaders are important for explaining investments in public goods. The argument holds that leaders with business experience make smaller contributions to collective defense because they are egoistic and more comfortable relying on a powerful ally for their defense. An analysis of defense expenditures in 17 non‐U.S. members of the North Atlantic Treaty Organization from 1952 to 2014 provides evidence consistent with the theory. The findings suggest that leaders with business experience are more likely than other heads of government to act as self‐interested utility maximizers.

Is there an ‘emboldenment’ effect: Evidence from the insurgency in Iraq
Jonathan Monten & Radha Iyengar Plumb
Journal of Strategic Studies, forthcoming


Does wartime debate in democracies during counterinsurgency campaigns embolden insurgent adversaries? Despite the historical frequency of this claim, there is little direct evidence assessing this ‘emboldenment’ hypothesis. This paper develops a novel test of this argument during the US counterinsurgency campaign following the invasion of Iraq in 2003. We find that following spikes in US domestic debate over the Iraq war, there is no evidence that insurgent attacks on military or civilian targets increased in regions of Iraq with greater access to US news compared to regions with less access. Overall, these results offer no support for the emboldenment claim.

Outside the Wire: U.S. Military Deployments and Public Opinion in Host States
Michael Allen et al.
American Political Science Review, forthcoming


How do citizens within countries hosting U.S. military personnel view that presence? Using new cross-national survey data from 14 countries, we examine how different forms of exposure to a U.S. military presence in a country affect attitudes toward the U.S. military, government, and people. We find that contact with U.S. military personnel or the receipt of economic benefits from the U.S. presence correlates with stronger support for the U.S. presence, people, and government. This study has profound implications for the role that U.S. installations play in affecting the social fabric of host nations and policy implications for the conduct of U.S. military activities outside the United States.

Arming in the global economy: The importance of trade with enemies and friends
Michelle Garfinkel, Constantinos Syropoulos & Yoto Yotov
Journal of International Economics, forthcoming


We analyze how trade openness matters for interstate conflict over productive resources. Our analysis features a terms-of-trade channel that makes security policies trade-regime dependent. Specifically, trade between two adversaries reduces each one's incentive to arm given the opponent's arming. If these countries have a sufficiently similar mix of initial resource endowments, greater trade openness brings with it a reduction in resources diverted to conflict and thus wasted, as well as the familiar gains from trade. Although a move to trade can otherwise induce greater arming by one country and thus need not be welfare improving for both, aggregate arming falls. By contrast, when the two adversaries do not trade with each other but instead trade with a third (friendly) country, a move from autarky to trade intensifies conflict between the two adversaries, inducing greater arming. With data from the years surrounding the end of the Cold War, we exploit the contrasting implications of trade costs between enemies versus trade costs between friends to provide some suggestive evidence in support of the theory.

Statistical sightings of better angels: Analysing the distribution of battle-deaths in interstate conflict over time
Céline Cunen, Nils Lid Hjort & Håvard Mokleiv Nygård
Journal of Peace Research, forthcoming


Have great wars become less violent over time, and is there something we might identify as the long peace? We investigate statistical versions of such questions, by examining the number of battle-deaths in the Correlates of War dataset, with 95 interstate wars from 1816 to 2007. Previous research has found this series of wars to be stationary, with no apparent change over time. We develop a framework to find and assess a change-point in this battle-deaths series. Our change-point methodology takes into consideration the power law distribution of the data, models the full battle-deaths distribution, as opposed to focusing merely on the extreme tail, and evaluates the uncertainty in the estimation. Using this framework, we find evidence that the series has not been as stationary as past research has indicated. Our statistical sightings of better angels indicate that 1950 represents the most likely change-point in the battle-deaths series – the point in time where the battle-deaths distribution might have changed for the better.

Hoping for Peace during Protracted Conflict: Citizens’ Hope Is Based on Inaccurate Appraisals of Their Adversary’s Hope for Peace
Oded Adomi Leshem & Eran Halperin
Journal of Conflict Resolution, forthcoming


Hope is an essential component in the pursuit of political change. In order to hope, citizens need to wish for the change and have some expectations that it could materialize. This article explores how the two components of hope (i.e., wishes and expectations) are constructed in the seemingly hopeless case of a protracted and violent conflict. Utilizing a large-scale survey administered in Israel, the West Bank, and the Gaza Strip, we show that citizens’ appraisals of their adversary’s wishes and expectations for peace affect their own wishes and expectations, which, in turn, influences their willingness to support peacebuilding efforts. Regrettably, citizens’ tendency to underestimate their rival’s wish for peace lessens their own hopes, which further abates the support for peacebuilding. The study is the first to illustrate a mechanism by which hope for peace is constructed and the pathways by which hope facilitates resolution. Theoretical and applied implications are discussed.

Information Operations Increase Civilian Security Cooperation
Konstantin Sonin & Austin Wright
University of Chicago Working Paper, September 2019


Information operations are considered a central element of modern warfare, yet there remains little, if any, systematic evidence of their effectiveness. Using a geographic quasi-experiment conducted during Operation Enduring Freedom in Afghanistan, we demonstrate that civilians exposed to the government’s information campaign resulted in more civilian security cooperation, which in turn increased bomb neutralizations. These results are robust to a number of alternative model specifications that account for troop presence and operations and other confounding factors. The core findings are also corroborated with evidence from a nationwide survey and large-scale analysis of intelligence reports and counterinsurgent operations. This note demonstrates that information campaigns can lead to welfare-enhancing attitudinal and behavioral changes in an adversarial environment and can substantially improve battlefield outcomes.

Atlantic Trade and the Decline of Conflict in Europe
Reshad Ahsan, Laura Panza & Yong Song
University of Melbourne Working Paper, December 2019


We use over 250 years of conflict and market integration data to provide the first evidence that Atlantic trade contributed to Europe's pacification between 1640 and 1896. While the decline in conflict in Europe during this period has been well documented, the role of Atlantic trade has not been previously explored due to a lack of historical trade data. We overcome this constraint by using wheat prices to calculate time-varying measures of market integration between Europe and the New World, which we use as a proxy for Atlantic trade. To identify the causal effects of Atlantic trade, we exploit exogenous changes in wind patterns and tropical cyclone activity over the Atlantic Ocean to instrument trade. Our results suggest that the growth in Atlantic trade between the mid-17th to the early 19th century lowered the probability of intra-European conflict onset by 14.90 percent. We find empirical support for two channels driving our results: first, Atlantic trade led to an increase in real wages and a reduction in both army and navy sizes in Europe. Second, we show that the possibility of forgone Atlantic trade acted as a deterrent to conflict.

Defending the Faith? Assessing the Impact of State Religious Exclusivity on Territorial MID Initiation
Ariel Zellman & Jonathan Fox
Politics and Religion, forthcoming


Interstate conflicts involving religion are commonly argued to be more severe and more protracted than other forms of conflict. Although various arguments have sought to explain religion's apparent contributions to global violence, few consider the foreign policy goals over which religious actors actually fight. This article does so by examining whether religiously-exclusive states tend to militarize interstate territorial disputes (MIDs) over issues of strategic material or identity salience. Insofar as religiously-exclusive states seek to “defend the faith” against internal and external challengers, identity-salient disputes should be a particularly attractive target for militarization. We however find the opposite. Although religiously-exclusive states do initiate territorial MIDs more frequently than their secular counterparts, they are significantly more likely to do so owing to disputed territories' strategic rather than symbolic value. These results challenge accepted wisdom regarding religion's influence on international conflict and suggest critical new avenues for research.

Foreign Policy as Pork-barrel Spending: Incentives for Legislator Credit Claiming on Foreign Aid
Tobias Heinrich & Timothy Peterson
Journal of Conflict Resolution, forthcoming


Foreign policy often creates geographically concentrated domestic benefits. A prominent example is the tying of development aid to purchases from the donor country. This feature of aid highlights the utility in examining foreign policy as an instance of pork-barrel politics. Considering tied aid in terms of legislators’ incentives to provide constituent benefits, we argue that people will support an increase in foreign aid spending more when it would promote local economic activity, while opposing aid cuts more when reduced local economic output would result. Crucially, we also expect that people will support their state’s US senator more when informed that the senator attempted to secure (or retain) locally beneficial funds. We find support for our expectations in a novel survey experiment of US citizens. Our results suggest that legislators’ electoral incentives, and consequential local spending, can help explain the adoption of foreign policies despite national-level public disapproval.


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