Not Gone with the Wind: Long-Run Impact of Herbicidal Warfare in Vietnam
利用美军飞行记录和村庄级除草剂暴露差异，研究发现越南战争期间除草剂暴露增加10%会导致2001年人口减少1.57%-1.93%，2020年减少2.42%-2.8%，且对人口增长率有负面影响。
We investigate the legacies of herbicidal warfare on population size and growth in Vietnam in 2001-2020. The identification strategy exploits the flight-level military records and the plausibly exogenous hamlet-level variation in herbicide exposure around the spray-on, direction-change, and spray-off points of fixed-wing aircraft missions, combined with a fuzzy regression kink design. The elasticity estimate suggests that a 10% increase in herbicide exposure during the Vietnam War is associated with a decrease in population size of 1.57-1.93% in 2001 and 2.42-2.8% in 2020. We also find negative associations between herbicide exposure and overall and annual population growth rates.