"Today, the elements of a perfect storm are in place around the world: an ample supply of weapons-usable nuclear materials, an expansion of the technical know-how to build a crude nuclear bomb, and the determination of terrorists to do it. This should be a grave concern for all of us. Terrorists don’t need to go where there is the most material; they are likely to go where the material is most vulnerable. That means the future of the nuclear enterprise, including the future of the nuclear power industry, requires that every link of the nuclear chain be secure—because the catastrophic use of atoms for terrorism will jeopardize the future of atoms for peace."
Senator Sam Nunn
11 November 2013
The international community has for some time been alarmed by the prospect of a terror or criminal organization acquiring possession of fissile material with the intent to weaponize it in a nuclear explosive device. A potential malefactor has two options for the acquisition of fissile material: first, to steal or divert the material from a state; or second, to manufacture the material. Of these, the former is considered more likely though the latter cannot, and should not be discounted.
For reasons explored later, it is more likely a terrorist or criminal organization would seek to move fissile material across transnational borders rather than attempt to transport a fully assembled nuclear explosive device, since the former is comparatively difficult to detect when properly shielded and concealed whereas the latter is susceptible to discovery. This being the case, nuclear smuggling more likely involves the movement of illicit fissile material than illicit nuclear explosive devices. Once illicit fissile material reaches its intended destination and is in a malefactor's possession, the malefactor can leverage its disruptive effect by means of an adequately supported claim simply to have such material in-country, without necessarily having taken the additional step to weaponize the selfsame material. However, fabricating an actual explosive nuclear device allows a malefactor to leverage both the disruptive and the destructive effects.
This paper explores the nature of weapons-usable fissile material; the several options by which a malefactor could gain possession of it; and the method and effect of weaponizing fissile material in an explosive nuclear device. That discussion is preamble to an exploration of the phenomenon of nuclear smuggling and detecting the movement of illicit fissile material for the purpose of interdiction. ...