Today, the origins of the concept of RW have largely been forgotten.  Indeed, since 9/11, radiological weapons have been associated mainly with non-state actors, who may not have the means or motivations to acquire and use far more lethal nuclear explosives.  A fixation on the very real dangers posed by nuclear terrorism, however, should not obscure the risks that states also may again pursue radiological weapons.

A comparative analysis of the United States’ and the Soviet Union’s previously underexplored radiological weapons programs identifies the drivers behind their rise and demise. The findings of this analysis illuminate the factors likely to affect the pursuit of radiological weapons by other states in the future.