Radiological and Nuclear Terrorism
Radiological weapons, while they have never been used, have the potential to cause large-scale disruption to a city that is attacked. Although radiological weapons are unlikely to cause massive numbers of casualties, the use of such devices may lead to social unrest and fear, and recovering from such an attack is likely to be lengthy and costly, possibly rendering large areas off-limits until clean-up is completed. In addition, many of our emergency responders and medical caregivers are unfamiliar with radiological emergencies, and it is possible that this lack of familiarity may complicate the response to a radiological emergency. For this reason, the threat of a radiological attack must be taken seriously.
Of particular concern is the availability of radioactive materials that might be used in such an attack. This was highlighted by a recent GAO investigation, in which a phony company received a radioactive materials license, which could have been used to purchase radioactive materials for illicit purposes. There have also been concerns raised that radioactive materials might be sold to a phony company overseas, only to be smuggled back into the US to be used in a terrorist attack.
If terrorists are successful in obtaining radioactive materials, they may choose to launch either an overt attack (a "dirty bomb") or a covert attack (sometimes called a "smoky bomb"). Much has been written about the former, and somewhat less about the latter. There are also several sites with information for emergency responders and medical professionals who are responding to a radiological attack. In addition to these web sites, there is a large literature on the impact of radiological terrorism. Links to related articles and papers are on the right side.
As potentially bad as a radiological attack may be, a terrorist attack using nuclear weapons would be disastrous. We know what such weapons would do, having seen the results in Japan at the end of the Second World War. A nuclear attack in a major city could leave hundreds of thousands dead and hundreds of thousands more injured - in addition to the financial, economic, psychological, and social impact.
Making a radiological device is very little more difficult than is making any other terrorist bomb. Making a nuclear device is far more complex; physics alone places many constraints on the potential nuclear bomb-maker, and obtaining sufficient quantities of fissionable materials is even more difficult; but not impossible. There is a great deal of information available that describes the basics of nuclear weapons design and, even if making a miniaturized high-yield weapon is beyond the reach of even most nations, making a weapon comparable to the ones used in Japan is entirely possible. (http://nuclearweaponarchive.org/). In addition, the proliferation of nuclear weapons technology (and the instability of some existing nuclear weapons states) raises other possibilities for the spread of nuclear weapons to terrorist organizations.
There is a tremendous literature on the effects of nuclear weapons. Perhaps the best single reference is, appropriately enough,The Effects of Nuclear Weapons, by Glasstone and Dolan. Another good book that discusses the thermal effects of nuclear weapons (e.g. mass fires, or "fire storms") is "Whole World on Fire" by Lynn Eden. Links to articles and papers on this topic are on the right side.
We have no way of knowing the likelihood of a radiological or nuclear attack, so it is difficult to decide how much time and effort to devote to preparing for a response to such an attack. However, we can expect that some effects from such an attack might be similar to what we might see from some other disasters, natural and otherwise. Some of these are summarized in the tables in which provided on the right side.