Description:
The complexity of the 21st century threat landscape contrasts significantly with the bilateral nuclear bargaining context envisioned by classical deterrence theory. Nuclear & conventional arsenals continue to develop alongside antisatellite programs, autonomous robotics or drones, cyber operations, biotechnology, & other innovations barely imagined in the early nuclear age. The concept of cross-domain deterrence emerged near the end of the George W. Bush administration as policymakers & commanders confronted emerging threats to vital American military systems in space & cyberspace. The Pentagon now recognizes five operational environments or so-called domains (land, sea, air, space, & cyberspace), & cross-domain deterrence poses serious problems in practice. This text steps back to assess the theoretical relevance of cross-domain deterrence for the field of international relations.