In recent years, much emphasis has been placed on responding to the consequences of an attack rather than on preventing terrorist acquisition or use of weapons of mass destruction.
On September 11, a small group of terrorists inflicted the level of death and destruction some feared might result from an attack by terrorists using sophisticated weapons of mass destruction (WMD). The skill of this group lay not in its ability to acquire exotic weapons materials but rather in its planning, organization, teamwork, and commitment to achieve a diabolic objective.
In the span of one hour, a group of 19 men, supported by others whose numbers are still not clear, fundamentally changed the national security landscape of the United States. The number of Americans killed on U.S. soil in these attacks raised a profound and frightening question about the defense of the country: are the suicide hijackings of September 11 just another step in an escalatory process that may lead radical antiAmerican terrorists to use nuclear, biological, or chemical weapons against American interests at home or abroad?
Since the 1995 attack by the Japanese cult group Aum Shinrikyo against the Tokyo subway with liquid sarin, the United States has had a heightened fear of terrorist use of weapons of mass destruction. One particular worry has been that Osama bin Laden and the al Qaeda network might exploit the chaos in Central Asia to seek to acquire WMD capabilities from former Soviet republics. The indictment of bin Laden for his alleged involvement in the bombing of U.S. embassies in Kenya and Tanzania claims that he has tried to acquire nuclear and chemical weapons, and one of the prosecution's witnesses in the bombing trial revealed that he had sought to acquire radioactive material on behalf of bin Laden and al Qaeda.
But turning radioactive material into a nuclear bomb is a hard task, even for a state with considerable industrial infrastructure and expertise, and the six years since the Tokyo subway attack have made that incident seem more like an aberration than a paradigm-breaking event that others copy. Aside from Aum Shinrikyo, open-source literature to date references no other significant terrorist organization that has used unconventional weapons repeatedly.1 Although attacks with weapons of mass destruction are possible, the historical record of states and terrorist groups using exotic unconventional weapons is quite limited.2 Terrorists appear more likely to use what they can readily acquire rather than to go through the difficult process of making weapons from scratch or stealing them from a state's arsenal.
In the last 25 years, terrorist use of conventional explosives has consistently proved far more deadly than the few instances of terrorism involving unconventional weapons. Many more people died or were injured in the attacks on the Murrah Federal Building in Oklahoma City and the U.S. embassies in East Africa than in the Tokyo subway attack. Although there is some evidence that, in recent years, terrorists have shown an interest in unconventional weapons, thus far they have employed more readily available means in ever more dramatic and deadly ways.
Nevertheless, the consequences of a successful WMD attack on American soil could be so catastrophic that serious government attention is warranted. In recent years, much of the emphasis has been on responding to the consequences of such an attack rather than preventing terrorist use or acquisition of weapons of mass destruction. Given the relative cost of prevention versus response, this emphasis seems misplaced. In a climate in which officials will go to extraordinary lengths for counterterrorism, spending smart is more important than just spending big.
Non-proliferation measures, cooperative threat reduction, and other arms control initiatives can help limit the opportunities for terrorists to acquire or develop WMD. Although the …