Meet the Experts

Graham T. Allison is the Douglas Dillon Professor of Government and director of the Belfer Center for Science and International Affairs at the John F. Kennedy School of Government at Harvard University. He served as assistant secretary of defense for policy and plans at the Department of Defense in the Clinton administration. Allison is the author of "Nuclear Terrorism: The Ultimate Preventable Catastrophe" (2004) and "Avoiding Nuclear Anarchy: Containing the Threat of Loose Russian Nuclear Weapons and Fissile Material" (1996).

Matthew Bunn is a senior research associate and acting executive director of the Project on Managing the Atom at the Belfer Center for Science and International Affairs at John F. Kennedy School of Government at Harvard University. He is an expert on the security of weapons-useable nuclear materials, and served as an adviser to the Office of Science and Technology Policy in the Clinton administration.

Daniel Hirsch has studied safety and security issues at university reactors for 27 years. He is the president of the Committee to Bridge the Gap, a Los Angeles-based advocacy group that provides technical and legal assistance to communities near existing or proposed nuclear sites. Hirsch is the former director of the Adlai Stevenson Program on Nuclear Policy at the University of California, Santa Cruz. In the 1980s, Hirsch fought to close the nuclear research reactor at University of California, Los Angeles, after he and his students discovered that radioactive gas from the reactor was leaking into the building where he taught. The UCLA reactor was eventually closed.

Ronald E. Timm is a senior consultant for RETA Security Inc., a for-profit company that has analyzed security for the Department of Energy and the Department of Defense. As a Department of Energy contractor, Timm has assessed security systems, both at the nation's major nuclear facilities and for the transportation of special nuclear material. For 15 years, he worked at the Department of Energy's Argonne National Laboratory, where he served as a senior project manager and security engineer.

Roy Zimmerman is the director of nuclear security and incident response at the Nuclear Regulatory Commission. The federal agency regulates more than 100 commercial nuclear power plants and 35 research and test reactors, including those located on university campuses. Zimmerman has been with the commission since 1978, and has served as a reactor inspector, division director, and deputy director in the Office of Nuclear Reactor Regulation.

Fritz Steinhausler is a professor at the Institute of Physics and Biophysics at the University of Salzburg in Austria. A nuclear physicist, he has co-authored several papers on the vulnerability of nuclear reactors to terrorist sabotage. In 2002, Steinhausler collaborated with Stanford University researchers to launch a database that tracks missing, stolen and recovered radioactive material worldwide.