SummaryLateral Pressure refers to any tendency (or propensity) of individuals and societies to expand their activities and exert influence and control beyond their established boundaries, whether for economic, political, military, scientific, religious, or other purposes. Framed by Robert C. North and Nazli Choucri, the theory addresses the sources and consequences of such a tendency.Lateral Pressure theory seeks to explain the relationships between state characteristics and patterns of international behavior. The theory addresses the sources and consequences of transformation and change in international relations and provides a basis for analyzing potential feedback dynamics. To the extent that states expand their activities outside territorial boundaries -driven by a wide range of capabilities and motivations -they are likely to encounter other states similarly engaged. The intersection among spheres of influence is the first step in complex dynamics leading hostilities, escalation, and eventually to conflict and violence. These processes are contingent on the actors' intents, capabilities, and activities.The causal logic in lateral pressure theory runs from the internal drivers, that is, the master variables that shape the profiles of states --through the intervening variables, namely, aggregated and articulated demands given prevailing capabilities --the outcome often generates added complexities. This paper proceeds as follows: First we highlight the basic features of lateral pressure theory, its core components, and their interconnections. Some aspects are more readily quantifiable than others. Some are more consistent with conventional theory in international relations. Others are based on insights and evidence from other areas of knowledge, thus departing from tradition in potentially significant ways. Second, we summarize the phases of empirical investigations and the evolution of theory over time. Third, we return to basics and focus on the refinements of metrics and quantification of the core concepts. All of this pertains to the world, as we have known it prior to the construction of the Internet, the core of cyberspace. Fourth, we then turn briefly to results so far of our o research on lateral pressure in the cyber domain. The Endnote highlights some emerging imperatives.
Keywords:Lateral pressure theory, cyberspace and traditional international relations, cyber challenges to the state system.