Lateral 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 (Choucri and North 1972; Choucri and North 1975; Ashley 1980; Choucri and North 1989; North 1990; Lofdahl, 2002). Framed by Robert C. North and Nazli Choucri, the theory addresses the sources and consequences of such a tendency.
In contrast to tradition in international relations, lateral pressure theory takes the position that all actors and entities are embedded in three interconnected systems namely the social system and its physical properties, the natural system and its life supporting properties and, more recently, the constructed cyber system and its enabling potentials for all actors and entities worldwide.
Lateral pressure is a relatively neutral concept similar to what Sorokin (1957, 565) called economic expansion and Simon Kuznets (1966, 334–348) referred to more broadly as outward expansion. The strength of a country's lateral pressure is generally taken to correlate positively with its power as conventionally understood. The theory of lateral pressure draws on the level of analysis or "Image" perspective in international relations (Boulding 1956; Waltz 1979), largely as an initial framing, and then extends this traditional perspective in specific ways.
When Choucri and North (1972; 1975) formulated the theory of lateral pressure in qualitative as well as quantitative terms they signaled that, in general, the strength of a country's lateral pressure correlates positively with its capabilities and power (a concept that is almost universally used but defined with difficulty). Lateral pressure theory provides a more detailed and nuanced view of the sources of power, the types of leverages used, and the behaviors that can be inferred. It suggests how certain types of international behaviors or activities appear to be more prevalent in some countries than others. Among the notable reviews of lateral pressure theory are Levy (2005), and Pollins and Schweller (1999). Lateral Pressure Basics summarize the elements of the theory.
Ashley, Richard K. 1980. The Political Economy of War and Peace: The Sino Soviet American Triangle and the Modern Security Problematique. London: F. Pinter.
Boulding, Kenneth E. 1956. The Image: Knowledge in Life and Society. Ann Arbor: University of Michigan Press.
Choucri, Nazli, and Robert C. North. 1972. "In search of Peace Systems: Scandinavia and the Netherlands, 1870–1970." In Peace, War, and Numbers, edited by B. M. Russett, and American Political Science Association, 239–274. Beverly Hills, CA: SAGE.
Choucri, Nazli, and Robert C. North. 1975. Nations in Conflict: National Growth and International Violence. San Francisco: W. H. Freeman.
Choucri, Nazli, and Robert C. North. 1989. "Lateral Pressure in International Relations: Concept and Theory." In Handbook of War Studies, edited by M. I. Midlarsky, 289–326. Boston, MA: Unwin Hyman.
Kuznets, Simon. 1966. Modern Economic Growth: Rate, Structure, and Spread. New Haven, CT: Yale University Press.
Levy, Jack S. 1998. "The Cause of War: A Review of Theory and Evidence." Annual Review of Political Science Vol. 1, 139–165.
Lofdahl, Corey L. 2002. Environmental Impacts of Globalization and Trade: A Systems Study. Cambridge, MA: MIT Press.
North, Robert C. 1990. War, Peace, Survival: Global Politics and Conceptual Synthesis. Boulder, CO: Westview.
Pollins, Brian M., and Randall L. Schweller. 1999. "Linking the Levels: The Long Wave and Shifts in U.S. Foreign Policy, 1790–1993." American Journal of Political Science 43(2), 431–464.
Sorokin, Pitirim. 1957. Social and Cultural Dynamics: A Study of Change in Major Systems of Art, Truth, Ethics, Law, and Social Relationships. New Brunswick, NJ: Transaction Books.
Waltz, K. N. 1979. Theory of International Politics. Reading, MA: Addison-Wesley.