The very mention of nuclear terrorism is enough to rouse strong emotions, and understandably so, because it combines the most terrifying weapons and the scariest people in a single phrase. The possibility that terrorists could use nuclear weapons deserves the best possible analysis, but discussion has all too often has been contaminated with exaggeration, even hysteria, that flows in at least some cases from the political interests commentators have in exaggerating the terrorist threat. For example, it has been claimed that nuclear terrorism poses an "existential threat" to the United States.
This "Adelphi Paper "develops a more measured analysis of the risk of nuclear terrorism, defined here as the detonation by terrorists of a device with a true nuclear yield. It attacks the problem from two angles: the very considerable, possibly insurmountable technical challenges involved in getting a functional nuclear weapon, whether "home-made" or begged, borrowed, or stolen from a state arsenal, and the related question of the strategic, political, and psychological motivation to "go nuclear." It concludes, with some other writers, that nuclear terrorism is not a significant threat, and that, among terrorists, Muslim extremists are not the most likely to go use nuclear weapons.

The very mention of nuclear terrorism is enough to rouse strong reactions, and understandably so, because it combines the most terrifying weapons and the most threatening of people in a single phrase. The possibility that terrorists could obtain and use nuclear weapons deserves careful analysis, but discussion has all too often been contaminated with exaggeration, even hysteria. For example, it has been claimed that nuclear terrorism poses anexistential threat to the United States. This Adelphi Paper develops a more measured analysis of the risk of terrorists detonating a true fission device. The problem is attacked from two perspectives: the considerable, possibly insurmountable, technical challenges involved in obtaining a functional nuclear weapon, whetherhome-made or begged, borrowed or stolen from a state arsenal; and the question of the strategic, political and psychological motivations togo nuclear. The conclusions are that nuclear terrorism is a less significant threat than is commonly believed, and that, among terrorists, Muslim extremists are not the most likely to use nuclear weapons.