and now includes 16 sectors: chemical; commercial facilities; communications; critical manufacturing; dams (including locks and levees); defense industrial base; emergency services; energy; financial services; food and agriculture; government facilities; health care and public health; information technology; nuclear reactors, materials, and waste; transportation systems; and water and wastewater systems (Federal Register 2013).
The national protection plan defines a broad spectrum of assets in need of security, which is complex and unwieldy with respect to unifying concepts and modeling for engineering purposes. In contrast, the concept of a “lifeline,” developed by the Technical Council on Lifeline Earthquake Engineering to evaluate the performance of large, geographically distributed networks during earthquakes (O’Rourke 2007), involves a smaller number of critical systems—electric power, gas and liquid fuels, telecommunications, transportation, waste disposal, and water supply. If flood and hurricane protection systems are added, one can identify a subset of seven geographically distributed networks that are intimately linked with the economic well-being, security, and social fabric of the communities they serve. Thinking about critical infrastructure through this subset of lifelines helps clarify common features and provides an effective framework for understanding interdependencies among the different systems.
Hurricane Katrina in 2005 challenged the 9/11 paradigm of protection of critical infrastructure. The hurricane protection system (HPS) of New Orleans was authorized by the US Congress under the 1965 Flood Control Act, and its design and construction were supervised by the US Army Corps of Engineers. But when Hurricane Katrina struck, the HPS was incomplete and no parish had the full level of protection authorized in 1965. As the Interagency Performance Evaluation Task Force concluded, the HPS “did not perform as a system”; it had been constructed in a piecemeal fashion over many years that represented a history of “continuous incompleteness” (IPET 2008).
A new paradigm emerged after Hurricane Katrina, centered on the concept of resilience, and much has been written and discussed about this concept. In current parlance, the resilience of an organization or community is an overarching attribute that reflects its degree of preparedness and ability to respond to and recover from shocks. The term has become the scaffolding on which to build a community or organization that is well prepared and responsive to a wide range of demands, including natural hazards and human threats. Current US policy for critical infrastructure is an amalgam of concepts and activities based on the development of community resilience and the protection of critical infrastructure.