Security, Peace & Conflict Workshop: Greg Smith (Duke University)

Talk title: The Dynamic Effect of Bombing in Vietnam

Existing research on bombing widely presupposes that the effect of bombing remains constant. Scholars ignore the fact that bombing creates pressure for the target to adapt in ways that mitigate the effects of the imposed policy. During the Vietnam War, for example, the North Vietnamese adapted to U.S. bombing by moving surface to air missiles (SAMs) into restricted zones around Hanoi and Haiphong that were off-limits to U.S. aircrews. This study introduces a new dynamic theory of bombing and measures how the effect of bombing changed throughout the Vietnam War by using instrumental variable models and a new variant of Marginal Structural models that rely upon Extreme Gradient Boosted Trees. The results show that bombing worked immediately to reduce territorial control, but that effectiveness attenuated quickly in hamlets where bombing was used repeatedly. Moreover, the results suggest that North Vietnamese insurgents moved into the areas surrounding hamlets to avoid U.S. bombing campaigns. In addition to challenging static theories of coercion, the results contradict the popular supposition that bombing is necessarily counterproductive due to the fact that it increases local support for the insurgent group.