The Elusive Promise of “Over-the-Horizon” Counterterrorism

Abstract

Amid criticism on the United States withdrawal from Afghanistan, President Biden described the future of U.S. counterterrorism as “over-the-horizon.” This term is derived from long-distance radar technology. It implies that security forces will be postured outside a conflict. Once intelligence reveals a plot, they will cross international borders, execute a strike, and prevent the attack. This has been tried before. In the 1980s and 1990s, national security staff advocated for periodic strikes and raids against terrorists. They failed. This article explores these failures. It examines declassified sources to understand risk-benefit calculations by the White House and finds that the juxtaposition of perceived risks associated with a single strike weighed against benefits derived from cumulative strikes makes presidents reluctant to approve over-the-horizon operations.