Terrorism for the most part is not mindless violence. Mass casualties do not serve the terrorists' goals and could alienate the population. Thus the detonation of a nuclear bomb or the deliberate dispersal of toxic nuclear material seem the least likely terrorist threats. However, terrorists might contemplate carrying out low-level nuclear incidents and hoaxes. The inconvenience and political repercussions will probably exceed the actual danger to public safety. At a far more gradual rate the possibilities of serious nuclear incidents may increase simply because the number of nuclear facilities will increase, and technical knowledge regarding nuclear devices will spread. Before then, however, more effective safeguards can be developed.
Jenkins, Brian Michael, Terrorism and the Nuclear Safeguards Issue. Santa Monica, CA: RAND Corporation, 1976. https://www.rand.org/pubs/papers/P5611.html. Also available in print form.
Jenkins, Brian Michael, Terrorism and the Nuclear Safeguards Issue, Santa Monica, Calif.: RAND Corporation, P-5611, 1976. As of September 09, 2021: https://www.rand.org/pubs/papers/P5611.html