With enemies like these

Kevin Lewis

January 17, 2018

Partisan Cues and Opinion Formation on Foreign Policy
Amnon Cavari & Guy Freedman
American Politics Research, forthcoming


How does the extension of party conflict to a foreign policy issue affect the ability of Americans to form an opinion about the issue? We test this using elite references and longitudinal public opinion data about the Israeli–Palestinian conflict, a salient foreign policy issue in the United States that is increasingly characterized by partisan divisions. Our findings demonstrate that since the turn of the 21st century, the availability and clarity of party cues have increased, as well as the share of Americans who hold an opinion about the issue. Applying regression models to individual-level data, we reveal that the extension of party conflict to this issue has made it easier for more Americans to form an opinion.

Mars or Mercury? The Geopolitics of International Currency Choice
Barry Eichengreen, Arnaud Mehl & Livia Chitu
NBER Working Paper, December 2017


We assess the role of economic and security considerations in the currency composition of international reserves. We contrast the “Mercury hypothesis” that currency choice is governed by pecuniary factors familiar to the literature, such as economic size and credibility of major reserve currency issuers, against the “Mars hypothesis” that this depends on geopolitical factors. Using data on foreign reserves of 19 countries before World War I, for which the currency composition of reserves is known and security alliances proliferated, our results lend support to both hypotheses. We find that military alliances boost the share of a currency in the partner’s foreign reserve holdings by 30 percentage points. These findings speak to current discussions about the implications of possible U.S. disengagement from global geopolitical affairs. In a hypothetical scenario where the U.S. withdraws from the world, our estimates suggest that long-term U.S. interest rates could rise by as much as 80 basis points, assuming that the composition of global reserves changes but their level does not.

Estimating the Amount of Nuclear Weapon-usable Material Outside Government Control Using Data on Reported Seizures
Valentin Stanev & Steve Fetter
Science & Global Security, Fall 2017, Pages 125-142


Terrorists could acquire nuclear weapons by using weapon-usable nuclear material that was stolen or otherwise diverted from legitimate authorities. Multiple well-documented seizures suggest the existence of a black market that draws on an unknown stock of weapon-usable nuclear material that is not under the control of authorities. We estimate the total amount of uncontrolled material based on publicly reported seizures and several different statistical methods and models. We estimate that 90 to 250 kilograms — sufficient for up to ten nuclear weapons — remain outside the control of legitimate authorities. While this estimate is subject to large uncertainties and potential bias, governments may have additional information about nuclear material seizures that could be used to improve estimates.

Negative Returns: U.S. Military Policy and Anti-American Terrorism
Eugen Dimant, Tim Krieger & Daniel Meierrieks
University of Pennsylvania Working Paper, October 2017


We investigate the effect of U.S. military aid and U.S. troop deployments on anti-American terrorism, using a sample of 106 countries between 1986 and 2011. We find that greater military commitment leads to more anti-American terrorism. We study the underlying mechanisms using a mediation analysis and show that both U.S. military aid and troop deployments in foreign countries do not improve local state capacity. Rather, we find that more military aid (but not troop deployments) is linked to poorer political-institutional outcomes in aid-receiving countries, explaining the positive association between U.S. military aid and anti-American terrorism. Our findings suggest that U.S. military policy does not make the United States safer from transnational terrorism.

Casualty Rates of US Military Personnel During the Wars in Iraq and Afghanistan
Matthew Goldberg
Defence and Peace Economics, January/February 2018, Pages 44-61


In Operation Iraqi Freedom, which ended in August 2010, nearly 3500 hostile deaths occurred among US military personnel and 32,000 more were wounded in action (WIA). More than 1800 hostile deaths occurred during Operation Enduring Freedom (in and around Afghanistan) through 2014 and about 20,000 were WIA. A larger proportion of wounded personnel survived in Iraq and Afghanistan than during the Vietnam War, but the increased survival rates were not as high as some studies have asserted. The survival rates were 90.2% in Iraq and 91.6% in Afghanistan, compared with 86.5% in Vietnam. The casualty rates varied between the conflicts in Iraq and Afghanistan and before, during, and after the respective surges. Amputation rates are difficult to measure consistently, but I estimate that 2.6% of all WIA and 9.0% of medically evacuated WIA from the Iraq and Afghanistan theaters combined resulted in the major loss of a limb. Elevated non-hostile death rates (including deaths due to accidents, illnesses, homicides, or suicides) resulted in about 220 more deaths in Iraq and about 200 more deaths in Afghanistan than would have been expected in peacetime among populations of the size deployed to those two conflicts.

War versus peace: Does military officer quality adjust?
Marigee Bacolod, Michael Griner & Chad Seagren
Applied Economics Letters, forthcoming


In this study, we demonstrate the quantity–quality trade-off between the size of the U.S. military force and the quality of its junior military leaders. We employ a difference-in-differences methodology and compare measures of job performance before and after to show that in periods of military force expansion, the average quality of U.S. Marine officers decline; the converse holds in times of relative peace. This has implications for both military effectiveness and understanding labour market dynamics.

Power, proximity, and democracy: Geopolitical competition in the international system
Jonathan Markowitz & Christopher Fariss
Journal of Peace Research, January 2018, Pages 78-93


Why do only some powerful states choose to develop power projection capabilities? To answer this question, we test the proposition that states choose to develop power projection capabilities when they face a competitive geopolitical environment. This proposition is derived from our theory, which is used to construct a new measure of the level of geopolitical competition that every state in the system faces. This measure incorporates each state’s relative geographic position to every other state in the international system, the relative amount of economic power of those other states, and the degree to which their interests are compatible. We then apply this unique country-year measure to test the proposition that competitive environments are associated with the development of power projection capabilities, as measured by the tonnage of naval ships maintained by each country in each year. We demonstrate that our measure helps explain the degree to which states choose to invest in power projection capabilities. This provides an explanation for why the world has been economically multipolar, but military unipolar, for the past quarter century, and why this might change in the future, as rising powers with incompatible interests are increasing their investment in power projection capabilities.

Outgroup members’ internal criticism promotes intergroup openness: The role of perceived risk
Melissa McDonald et al.
British Journal of Social Psychology, forthcoming


Research suggests that hearing an outgroup member voice internal criticism increases individuals’ openness to the outgroup's perspective. We replicate and extend these findings in the context of the Israeli–Palestinian conflict. Israeli participants exposed to a Palestinian official voicing internal criticism reported more openness to the Palestinian narrative of the conflict, an effect that was mediated by an increase in participants’ perception that Palestinians are open-minded and a subsequent increase in their hope for more positive relations between the two groups. In our extension of these findings, we examined a complementary mechanism contributing to the effectiveness of the criticism manipulation, specifically the extent to which participants perceive that the Palestinian official took a risk voicing criticism of Palestinians. Positive messages from a hostile outgroup may be received with suspicion, but if they are articulated under great risk to the speaker, greater credibility may be granted. Across two studies, we demonstrate that the criticism conveys risk to the speaker and that this risk is predictive of the perceived credibility of the speaker, and participants’ subsequent openness to the outgroup's perspective.

Testing the impact and durability of a group malleability intervention in the context of the Israeli–Palestinian conflict
Amit Goldenberg et al.
Proceedings of the National Academy of Sciences, forthcoming


Fostering perceptions of group malleability (teaching people that groups are capable of change and improvement) has been shown to lead to short-term improvements in intergroup attitudes and willingness to make concessions in intractable conflicts. The present study, a field intervention involving 508 Israelis from three locations in Israel, replicated and substantially extended those findings by testing the durability of a group malleability intervention during a 6-month period of frequent violence. Three different 5-hour-long interventions were administered as leadership workshops. The group malleability intervention was compared with a neutral coping intervention and, importantly, with a state-of-the-art perspective-taking intervention. The group malleability intervention proved superior to the coping intervention in improving attitudes, hope, and willingness to make concessions, and maintained this advantage during a 6-month period of intense intergroup conflict. Moreover, it was as good as, and in some respects superior to, the perspective-taking intervention. These findings provide a naturalistic examination of the potential of group malleability interventions to increase openness to conflict resolution.

Minimizing Unintended Deaths Enhanced the Effectiveness of Targeted Killing in the Israeli–Palestinian Conflict
Ophir Falk & Amir Hefetz
Studies in Conflict & Terrorism, forthcoming


Targeted killing has become a primary counterterrorism measure used by a number of countries in their confrontation with lethal threats. This article focuses on the impact of unintended deaths on the effectiveness of targeted killing. The article evaluates the effectiveness of targeted killings carried out in the Israeli–Palestinian conflict theater that resulted in unintended deaths, compared to the effectiveness of targeted killings where the intended target is the sole person killed. Using multivariate analysis, we demonstrate that targeted killings with unintended deaths were followed by a greater number of suicide bombings and associated casualties compared with targeted killings with no unintended deaths. Based on these findings, nations involved in such conflicts should strive to inflict as few unintended deaths as possible, not only because it is morally right, but also because it is more effective in mitigating terrorism.

Which wars spread? Commitment problems and military intervention
Zachary Shirkey
Conflict Management and Peace Science, forthcoming


This article argues that wars caused by commitment problems are more likely to experience outside military intervention than are wars with other causes. Wars caused by commitment problems are more likely to draw in outside states because they tend to be more severe and produce larger war aims. These larger stakes create both threats and opportunities for non-belligerent states thereby prompting military intervention. The greater stakes also generate incentives for belligerent states to seek outside aid. This relationship between commitment problems and intervention implies that while certain types of wars may be more likely to experience intervention, the same causes can explain both intervention and war initiation. The argument is tested on the Correlates of War Interstate War dataset using logit-based generalized linear models. The findings support the commitment problem hypothesis and have implications for the bargaining framework and for theories about the causes of multilateral and general wars.

The 22 September 1979 Vela Incident: The Detected Double-Flash
Christopher Wright & Lars-Erik De Geer
Science & Global Security, Fall 2017, Pages 95-124


On 22 September 1979 two optical sensors on U.S. satellite Vela 6911 detected a double-flash of light that appeared characteristic of an atmospheric nuclear explosion conducted over the southern Atlantic or Indian Ocean. It became known as the Vela Incident, Event 747, or Alert 747. An anomaly between the amplitude of the two signals during the second pulse led a U.S. government expert panel established to assess the event to conclude in mid-1980 that a more likely explanation was the impact of a small meteoroid on the satellite, the debris from which reflected sunlight into the sensors' field of view. No model was presented to support the contention, and a similar anomaly — known as background modulation — was a given for the second pulse of all confirmed explosions detected by Vela, though beginning later. Nonetheless, this event has remained the subject of intense debate. This article reviews the evidence and presents an updated analysis of the original Vela signal based on recently declassified literature and on modern knowledge of interplanetary dust and hyper velocity impact. Given the geometry of the satellite, and that the bulk of the surface comprised solar panels, much of the debris from any collision would be carried away from the sensors' field of view. Thus, a meteoroid collision appears much less likely than previously assumed. The double flash is instead consistent with a nuclear explosion, albeit detected by an aged satellite for which background modulation was abnormal and/or commenced earlier, also seen in post-event SYSTEM tests. A companion paper to be published in 2018 presents radionuclide and hydroacoustic evidence supporting the conclusion that the Vela Incident was a nuclear weapon test explosion.


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