Arid regions of Africa are expanding by thousands of square kilometers a year, potentially disturbing pastoral routes that have been forged over a long period of time. This disturbance is often said to explain why "herder-farmer" conflicts have erupted in recent years, as pastoralists and...

We investigate the long-run effects of cooling on conflict. We construct a geo-referenced and digitized database of conflicts in Europe, North Africa, and the Near East from 1400-1900, which we merge with historical temperature data. We show that cooling is associated with increased conflict....

How does the interplay of geography and political-economic forces affect the shape of nations? This paper presents a quantitative framework for characterizing the equilibrium evolution of national boundaries in a world with a rich geography. The framework delivers simple equilibrium conditions...

Much has been written about deterrence, the process of committing to punish an adversary to prevent an attack. But in sufficiently rich environments where attacks evolve over time, formulating a strategy involves not only deterrence but also appeasement, the less costly process of not responding...

This paper investigates the economic effects of conflict, using the terrorist conflict in the Basque Country as a case study. Our analysis rests on two different strategies. First, we use a combination of other regions to construct a 'synthetic' control region which resembles many relevant...

This paper provides a formal model of endogenous country formation and of choice of defense spending in a world with international conflict. The model is consistent with three observations. First, secessions and, more generally, break-up of countries should follow a reduction in the likelihood...

Mechanism design teaches us that a mediator can strictly improve the chances of peace between two opponents even when the mediator has no independent resources, is less informed than the two parties, and has no enforcement power. We test the theory in a lab experiment where two subjects...

Natural resources have driven both growth and conflict in modern Africa. We model the interaction of parties engaged in potential conflict over such resources. The likelihood of conflict depends on both the absolute and relative resource endowments of the parties. Resources fuel conflict by...

This paper provides evidence of the long-run effects of a permanent increase in agricultural productivity on conflict. We construct a newly digitized and geo-referenced dataset of battles in Europe, the Near East and North Africa covering the period between 1400 and 1900 CE. For variation in...

In recent years, cases in which state governments chose to override federal environmental regulation with tighter regulations of their own have become increasingly common, even for pollutants that have substantial spillovers across states. This paper argues that this change arose at least in...