This book examines one manifestation of the general technical competition between terrorist groups and security organizations—the balance between the potential use by terrorists of advanced conventional weapons and the responses available to deter or counter them. Our use of the termadvanced conventional weaponsis inclusive and broad: any new or unusual conventional weaponry developed for ordinary military forces. Such weaponry seems a priori likely to be particularly threatening in the hands of terrorists. All weaponry is obviously designed to do damage, but new design features might enable new, or at least unfamiliar, terrorist attacks. At the same time,...

While considerable attention is being directed to potential terrorist use of unconventional weapons such as chemical, biological, radiological, and nuclear (CBRN) weapons, relatively little attention has been directed to potential terrorist use of advanced conventional weapons. The November 2002 attacks in Mombasa, Kenya, using Russian-made man-portable air defense systems (MANPADS) against an Israeli airliner, attributed by some to al Qaeda, demonstrated that some terrorists are willing and interested in using relatively unfamiliar, advanced weaponry.¹

Our use of the termadvanced conventional weaponsis inclusive and broad: any new or unusual conventional weaponry developed for ordinary military forces. This is essentially...

Although most modern military weapons are more powerful than similar antecedents, many may be implausible for terrorist use. For example, there is little likelihood that a terrorist group would attempt to acquire and use a main battle tank or a jet fighter. Similarly, a large warship would be of little practical value to terrorists. As a result, the types of military weapons on which this book focuses are relatively small, person- or light-vehicle transportable systems that would be relatively easy to conceal and use. Most are systems that one person or a small group could employ. The research team sought...

In assessing the attractiveness of a particular advanced conventional weapon system to terrorist adversaries, the central consideration must be the potential benefit that the terrorist organization might gain by acquiring and using the weapon. Having examined a variety of next-generation weapons, it is clear that there are many potentially dangerous conventional weapons being introduced into the inventories of modern military forces around the world. However, most of the weapons improve upon the lethality, usability, or reliability of existing weapons on the margin. As such, these new weapons are excellent candidates for replacing obsolete weapons but, from a homeland security perspective,...

Given the potential hazard of some advanced conventional weapons should they be diverted into terrorists’ hands, mechanisms for denying or limiting the utility of such weapons are clearly desirable if they do not interfere excessively with the military utility of advanced conventional weapons. The established mechanisms for controlling the use of weapons by unauthorized users are known by the termuse controls. Use controls can be thought of as a collection of procedural, technical, and policy tools that arrayed together can limit access to, and ability to use, advanced conventional weapons. Some controls are focused on preventing the underlying technology...

Whether or not a terrorist group pursues a new, advanced weapon can be framed as a judgment about costs and benefits. In this context, the choice to seek a specific weapon will depend on the terrorist group’s assessment of how potential benefits compare with the costs of obtaining a weapon and on how the apparent costs and benefits of that advanced weapon compare with other tactical and technological options available to the group. This calculus may be an implicit rather than an explicit process, and decisions may be based on cost and benefit criteria that are idiosyncratic to the terrorist...

This research started with two basic questions, which can now be answered:

What difference would it make if terrorists could use advanced conventional weapons in their attacks?

What could the United States do to reduce this threat?

Most advanced conventional weapons are not discussed in depth in this monograph because they do not appear to be particularly attractive to terrorists. In many cases, terrorists already have roughly equivalent weapons at their disposal, and incremental improvements will not significantly increase their attack capabilities. For example, although an improved explosive might enable terrorists to make a truck bomb smaller, existing truck bombs...