The international community faces no greater risk to peace and security than the nexus of terrorists and weapons of mass destruction. While recent years have brought us ever more serious terrorist attacks, such as the September 11, 2001 attacks, the Madrid train bombing, the attack on the school in Beslan, Russia, and the London subway bombings, the international community has not yet suffered a catastrophic terrorist attack involving nuclear, biological, chemical, or radiological weapons. However, the anthrax attacks suffered by the United States in 2001 and the sarin attacks suffered by Japan in 1995 provided an early warning regarding the risks posed by weapons of mass destruction in the hands of terrorists.
As we begin the 21st century, a variety of factors have increased the threat of terrorists acquiring and using weapons of mass destruction. First, certain terrorists groups, such as Al Qaeda, have openly declared their intention to acquire and use weapons of mass destruction against innocent civilian populations. Second, the fall of the former Soviet Union and the existence of other failed or weakened states have increased the probability that terrorists or their facilitators will seek to steal or smuggle nuclear, biological, or chemical weapons stocks. Third, the Internet and the development of digital and mobile communications, and the onset of globalization and other technological advances have enabled terrorist groups to acquire quickly the expertise and coordinate the delivery of WMD through extended, transnational networks.
In recent years, terrorists have shown a remarkable capacity to adapt to measures taken to combat their activities and escape the reach of the rule of law. In some cases, they take advantage of safe havens in territories or locations that lack a robust legal or regulatory infrastructure or law enforcement and security capabilities, or worse, have governments that are witting collaborators in terrorist activities. Terrorists also rely on elaborate transportation, logistics, and travel capabilities to move personnel, material, and related capabilities necessary to plan for and carry out attacks. In still other cases, terrorists intrude into "virtual spaces" such as modern financial or communications networks to incite or carry out the preparations for ever more lethal attacks, including those involving weapons of mass destruction.
A comprehensive and systematic approach to reducing the risk of a WMD terrorism attack involves 1) reducing the probability that terrorists will attack a given target in a given manner during a given time period (threat), 2) reducing the probability that a given attack with result in damage to a given target (vulnerability), and 3) reducing the expected damage of a successful terrorist attack on a given target (consequence). As we work to reduce further the probability of terrorist attacks involving WMD, we must take additional measures to reduce our vulnerabilities to and the consequences from such attacks.