
Gray zone security challenges, existing short of a formal state of war, present novel complications for U.S. policy and interests in the 21st century. We have well-developed vocabularies, doctrines and mental models to describe war and peace, but the numerous gray zone challenges in between defy easy categorization. For purposes of this paper, gray zone challenges are defined as competitive interactions among and within state and non-state actors that fall between the traditional war and peace duality. They are characterized by ambiguity about the nature of the conflict, opacity of the parties involved, or uncertainty about the relevant policy and legal frameworks.