Critical Infrastructure Protection in Homeland Security: Defending a Networked Nation, 2nd Edition

3Theories of Catastrophe

The study of critical infrastructure protection (CIP) and homeland security in general is more than the study of terrorist attacks, natural disasters, and accidents. In fact, there is a rich theoretical basis for the study of catastrophes, complex systems, and the relationship between complexity and failure of CIKR systems. This chapter traces the historical development of the three major theories: Perrow’s normal accident theory (NAT), Bak’s theory of punctuated equilibrium, and the more recent insights obtained by applying complex adaptive systems theory to CIP.

Biological and ecological systems are among the most complex systems in existence. It is not surprising, then, that principles observed in biological systems also apply to human-made CIKR systems. These principles are often expressed in terms of paradoxes and parables such as the tragedy of the commons (TOC), paradox of enrichment (POE), paradox of redundancy (POR), and competitive exclusion principle (CEP). The combination of NAT, complexity theory, and a handful of biological principles forms the basis of a comprehensive and modern theory of catastrophes.

This chapter surveys the three theories and develops new measures and insights into complex CIKR systems by borrowing principles from biology as follows:

• NAT: Charles Perrow’s 1979 theory states that extreme events occur when two or more failures occasionally come together in an unexpected way, are accelerated and increased in severity ...