From the thesis abstract: "As the United States confronts threats in a post Cold War era it increasingly finds itself in conflict with non-state actors. Many of the non-state enemies of the United States show an interest in acquiring nuclear or biological weapons in order to employ those weapons against the United States or its allies. Terrorist organizations wishing to acquire and use such weapons require intentional or accidental assistance from state actors. Currently the United States relies primarily on diplomatic and economic means to prevent terror acquisition and employment of such weapons. The current methodology does not appear to succeed in its desired ends. If the United States is to survive, it needs to entertain new deterrent alternatives. Announcing a new policy that includes a limited nuclear retaliation option directed against any state sponsor of a terrorist network that employs a high yield nuclear or biological weapon may have a significant deterrence and compellence effect on state sponsors of terrorism and their proliferation of nuclear and biological weapons."
Defense Technical Information Center (DTIC): http://www.dtic.mil/dtic/