"It's not a matter of if, it's a matter of when" says one anti-terror expert. Defense expert Graham Allison believes not enough has been done to prevent the unthinkable.
Click one of the "Listen" links to hear about the very real threat of nuclear terror on American soil, and what can be done to stop it.
Graham Allison, Director of the Belfer Center for Science and International Affairs at Harvard's Kennedy School of Government, former Assistant Secretary of Defense for Policy and Plans and author of "Nuclear Terrorism: The Ultimate Preventable Catastrophe."
This program aired on August 18, 2004.