This study uses discontinuities in U.S. strategies employed during the Vietnam War to estimate their causal impacts. It identifies the effects of bombing by exploiting rounding thresholds in an algorithm used to target air strikes. Bombing increased the military and political activities of the communist insurgency, weakened local governance, and reduced non-communist civic engagement. The study also exploits a spatial discontinuity across neighboring military regions, which pursued different counterinsurgency strategies. A strategy emphasizing overwhelming firepower plausibly increased insurgent attacks and worsened attitudes towards the U.S. and South Vietnamese government, relative to a hearts and minds oriented approach.
