The age of reductionism is over, new laws of physics are being discovered, and the old theoretical constructs are being replaced with new understanding. The modern operating environment in common with the world of physics has changed. This change, brought on by globalization and the increased integration of global communication, economic and informational systems, brings new challenges to those responsible for maintaining the security of the nation-state. This monograph initially examines the current operational environmental models for the UK and USA assessing their relevance to theory in light of changes that have taken place globally since the publishing of those documents. The paper then examines the modern threat and environment in which that threat may act in order to place this combination into a theoretical construct. Chapter 5 presents a theoretical model based on the ideal gas law, for the modern operating environment following analysis of the future threat and future arenas of operation. In conclusion, this monograph analyzes the effect of the thesis findings by briefly considering their implication on the standard campaign-planning model for the USA and UK. Further study in the area noted in the concluding chapter should be undertaken in order to refine this theoretical model, test the suppositions contained herein, and produce a better resolution with regard to the shape and structure of the future operating environment.