lead to widespread or catastrophic failures. In addition the high level of interconnectedness of these systems means that the abuse, destruction, or interruption of any one of them quickly affects the others. As a result the whole society is vulnerable, with the welfare and even lives of significant portions of the population placed at risk.

Second, as technology advances, the means of mass destruction are falling into the hands of smaller and smaller entities. In the war against terrorism, the enemy may be living among us and is largely unknown, or at least unidentifiable. Today that enemy includes international terrorist organizations such as al Qaeda, operating from overseas bases and supported or protected—and possibly assisted—by a variety of states and independent sources.1 It also includes home-grown fanatics.

These two trends affect all societies and their increasing vulnerability to terrorism, but the United States has a particular need for protection because its military preeminence makes terrorism virtually the only method by which those who wish to take violent action against it can do so. Moreover, U.S. vulnerability is exacerbated by some of the features that its people most treasure—freedom, personal initiative, openness, mobility—and that technology has helped make possible.

Catastrophic Terrorism

Terrorism—commonly defined as attack on the innocent, outside the context of organized armed conflict, with the objective of spreading fear and intimidation—has always been a danger to society. But what is new and especially troubling about the above two trends is their potential to combine, giving rise to the fearsome risk that the welfare of the many may be held hostage by the few—what this report calls “catastrophic terrorism.”

While science and technology can be used to combat all forms of terrorism, this report focuses on catastrophic terrorism. It is not possible to quantify catastrophic terrorism or to precisely distinguish it from “ordinary” terrorism;2 this


Gerald Holton, in a presentation in 1976, identified an emerging combination threat from what he called type III terrorism: nonstate groups of terrorists operating transnationally (type I terrorists) with the financial, logistic, and technical help of failed states (type II terrorists). For this reason it must not be assumed that terrorists will be unable to avail themselves of technologies that require a government level of investment for their development and acquisition (“Reflections on Modern Terrorism,” in Edge, available online at <http://www.edge.org/3rd_culture/holton/holton_print.html>, and based on a presentation at the Conference on Terrorism (1976) and a publication in Terrorism: An International Journal in 1978.)


Terrorism in general is difficult to define. According to the State Department’s annual publication Patterns of Global Terrorism, “No one definition of terrorism has gained universal acceptance.” The State Department uses the definition contained in Title 22 of the United States Code, Section 2656f(d): “The term terrorism means premeditated, politically motivated violence perpetrated against

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