Nuclear terrorism presents an unparalleled threat to the United States. The economic impact alone of a nuclear terrorist attack would undoubtedly be staggering. Estimates of the direct economic cost of one potential scenario--a crude nuclear device detonated in lower Manhattan--range well over $1 trillion. Even this estimate cannot capture the full tragedy of such a scenario, which could include half a million deaths, a zone of total destruction one mile wide, and radiation extending for miles around the blast's center. For the protectors of America's national interest, no single issue is more urgent and frightening.
Such a scenario is a real possibility. As Graham Allison and Andrei Kokoshin wrote in these pages, "we must first be prepared to imagine the unimaginable--there is a substantial probability that within the next decade, an act of nuclear terrorism will occur."1 These authors, and most who study the issue, reach this dire conclusion because a terrorist group needs to acquire only several kilograms of nuclear material to construct a functioning bomb out of the more than 2,000 metric tons of nuclear material that exist around the world.
Thankfully, nuclear terrorism is a finite problem. Simply put, nuclear terrorism is impossible without nuclear material, and the amount of nuclear material is finite. The quantities that exist can be counted and, in principle, comprehensively secured. Additionally, the production of new nuclear material is beyond the technological reach of terrorist organizations, barring state sponsorship.
