In 1945, the United States put a final and definitive end to World War II when it used two atomic bombs on Japan, forcing their surrender. At that time the entire world learned of the terrible potential of weapons of mass destruction. Unfortunately, as the major nations have backed away from weapons of mass destruction (WWD), terrorist organizations have sought to acquire them. Worse, technological advances have made it possible for to be constructed on a small enough scale that they could feasibly be smuggled anywhere in the world. .

             We have seen isolated use of such weapons. Terrorists released the nerve gas Sarin into a Tokyo subway some years ago, anthrax was used in the United States with the Postal Service as the delivery method, and al-Qaeda killed thousands in 2001 by flying fuel-laden passenger planes into buildings (Quillen, 2002). The last event in particular demonstrated that some groups want to leave a large mark from their terrorist activities, making the threat of WWD in their hands a real threat. .

             One of the greatest concerns of those charged with protecting us from terrorist attacks is that of nuclear and radiological devices. The word "nuclear" immediately puts fear in people because what we know of nuclear weapons is the kind of wide-scale obliteration that occurred in Nagasaki and Hiroshima at the end of World War II. However, there are two kinds of nuclear weapons terrorists might use. One threat is more realistic than the other. .

             Nuclear weapons are strategic armaments built by countries for offensive and defensive purposes. They are relatively difficult to build and to use, and most countries keep careful track of them, making them hard for terrorists organizations to acquire and hard for them to use. A second kind of nuclear device has been called a "dirty bomb," but can also be called a "radiological dispersion device," or RDD. One of the biggest risk factors with RDD's is that they can be constructed from nuclear waste materials, which are not nearly as well controlled as nuclear weapons are.