Essays in the political economy of conflict and development

This dissertation analyzes the economic causes of civil conflict and political strife. My first essay, joint with Juan Vargas, assesses how income shocks affect armed conflict. We exploit exogenous shocks in international commodity prices and a rich dataset on civil war in Colombia to analyze this question. We find that price shocks to labor-intensive agricultural commodities and capital-intensive natural resources affect conflict in opposite directions. A sharp fall in coffee prices in the 1990s increased violence differentially in coffee intensive regions, by lowering wages and the opportunity cost of joining armed groups. In contrast, a rise in oil prices increased violence differentially in oil regions, by increasing local government revenue which is siphoned by armed groups. My second essay analyzes how U.S. military aid affects political violence and democracy, using data from Colombia. Since military aid is channeled to Colombian army brigades operating out of military bases, I compare how changes in aid affect outcomes in municipalities with and without bases. I instrument aid to Colombia with aid to countries outside of Latin America. I find that U.S. military assistance leads to differential increases in attacks and political assassinations by paramilitaries (who are allied with the military), but has no significant effect on guerilla violence. Voter turnout also falls more in base municipalities during regional elections. These findings suggest that military aid may strengthen armed non-state actors, undermining domestic political institutions. My third essay addresses how immigration affects the educational achievement of non-immigrant students. I use data from over 4700 public elementary schools in California and proxy for the share of foreign-born students with the share of students who speak English as a second language. Exploiting cohort-to-cohort variation within a grade within a school, I find that a rise in the proportion of non-English proficient students leads to modest, but significant declines in the test scores of native students, in both Math and English. The analysis suggests that there may be real competition over access to local public goods such as education, addressing one key impetus behind the political strife around immigration.