Though approximately one in four coup attempts takes place during an ongoing civil war, scholars have not yet analyzed how the incidence of civil war affects coup attempts and outcomes. We conduct the first empirical analysis of the relationship between ongoing civil war and coup activity, finding (1) war increases the risk of a coup attempt, though (2) war-time coup attempts are significantly less likely to be successful, and (3) the risk of war-time coup is much higher when states face stronger rebel groups that pose greater threats to the political survival of the incumbent government. We attribute these findings to the pernicious effect of ongoing war on the welfare of the military elites and soldiers who have the greatest capacity to execute a coup attempt. As war diminishes their welfare and creates uncertainty about the future of the state, potential plotters become more willing to accept riskier coup attempts than they might plot during peace-time. Coup motivations are greatest when incumbents are more likely to lose their wars, and this causes coup plotters to attempt more and riskier coups when rebels are relatively strong.

As anthropogenic activities warm the Earth, the fundamental solution of reducing greenhouse gas emissions remains elusive. Given this mitigation gap, global warming may lead to intolerable climate changes as adaptive capacity is exceeded. Thus, there is emerging interest in solar radiation modification, which is the process of deliberately increasing Earth’s albedo to cool the planet. Stratospheric aerosol injection (SAI)—the theoretical deployment of particles in the stratosphere to enhance reflection of incoming solar radiation—is one strategy to slow, pause, or reverse global warming. If SAI is ever pursued, it will likely be for a specific aim, such as affording time to implement mitigation strategies, lessening extremes, or reducing the odds of reaching a biogeophysical tipping point. Using an ensemble climate model experiment that simulates the deployment of SAI in the context of an intermediate greenhouse gas trajectory, we quantified the probability that internal climate variability masks the effectiveness of SAI deployment on regional temperatures. We found that while global temperature was stabilized, substantial land areas continued to experience warming. For example, in the SAI scenario we explored, up to 55% of the global population experienced rising temperatures over the decade following SAI deployment and large areas exhibited high probability of extremely hot years. These conditions could cause SAI to be perceived as a failure. Countries with the largest economies experienced some of the largest probabilities of this perceived failure. The potential for perceived failure could therefore have major implications for policy decisions in the years immediately following SAI deployment.

Can the discovery of petroleum resources increase the risk of civil conflict even before their exploitation? We argue that it can, but only in poorer states where oil revenues threaten to alter the balance of power between regimes and their opponents, rendering bargains in the present obsolete in the future. We develop our claims via a game‐theoretic model of bargaining between a government and a rebel group, where decisions over war and peace occur in the shadow of increasing oil wealth that both increases national wealth and shifts relative power in the government's favor. To test the model's main hypothesis, we leverage data on newly discovered oil deposits as an indicator of the state's expected future power resources. Our argument has important implications for the literature on credible commitments, power shifts, and violent conflict.

This article explains coup activity in democracies by adapting insights from the literature on commitment problems and framing coup around the threats leaders and potential coup plotters pose to each other. I claim democratic constraints on executive power inhibit a leader’s ability to repress threats from political rivals. Though this decreases motivations for coup attempts, it also makes democracies more vulnerable should a coup attempt occur. Consequently, democratic constraints on executive power do not reduce the frequency of coup attempts, but coups attempted against democracies are much more likely to succeed. Using several data sets of coup activity and democratic constraints, I find significant differences in coup activity in democracies and non-democracies. Relative to civilian non-democracies, democracies are about half as likely to use coup-related repression, but they face a similar frequency of coup attempts. Plots against democracies are nearly twice as likely to succeed.

How does the way a non-democratic leader takes power affect the stability of her government? Prior research identifies irregular leader entries-those violating the regime's norms for leader selection-to be especially likely to foreshadow subsequent unconstitutional transitions. This paper shows how some forms of irregular leader entry can actually protect leaders from most threats of forced removal from power. When leaders use a strong and loyal coalition of supporters to overthrow their predecessors and their entire ruling regimes, as they do in successful rebellions, popular uprisings, and major regimechanging coups, they explicitly prove their strength to any potential rivals. These leaders are substantially less likely to be ousted than leaders who take power in ways that do not convey strength so convincingly, such as normal succession and elite reshuffling. We analyze an original dataset of non-democratic leader transitions and show that accounting for the strength demonstrated during a leader's entry to power substantially improves our ability to predict how and when the leader will eventually leave office. * NOTE: The data and all computer code necessary to replicate the results and figures in this analysis will be made publicly available at the authors' homepage on publication. R and Stata 14 were used for all statistical analyses.