Discussions of the logic of deterrence, both theoretical and practical, dominated the literature on just war theory during the Cold War. Despite diminished attention, the topic remains of vital importance to the current national security concerns, playing a central role in debates over Cyberwarfare and the use of non-conventional weapons or strategies. This Roundtable seeks to revive traditional discussions about the logic of deterrence, but to place this topic in a contemporary setting. Many of the former questions at the intersection of rational choice theory and ethics apply with renewed force in a post-Cold War world: Is it permissible to threaten to do something it would not otherwise be permissible to do? Does precommitment to an otherwise impermissible course of action render it permissible, given that it is accompanied by advance warning? Does deterrence require public notice to constitute a legitimate public policy? These older theoretical questions prove particularly challenging in an age of highly advanced technologies of war. How does deterrence work if the threatened attack cannot be traced back to the state that launched it? How should deterrence theory handle enemies whose actions are highly unpredictable and decentralized, and where the primary actors might not be interested in sparing civilian lives or even avoiding their own death? Is it legitimate to issue threats of kinetic action to deter a Cyber attack? Given the complexities of modern warfare and counter terrorism operations, the challenges of deterrent theory are now ripe for reexamination.