Research Questions

  1. What is critical infrastructure and how is it categorized?
  2. How are critical infrastructure sectors related? How severe are cascade effects from attacks on various sectors?
  3. What are some key threat prevention areas that should be addressed?

U.S. critical infrastructure supports the prosperity of the nation and its people. It permeates the daily lives of citizens, underpinning the safety and security of the general public and ensuring the economic well-being of the nation, yet the health of these assets, systems, networks, and facilities is often taken for granted. In this report, the authors analyze threats and hazards to critical infrastructure and examine the vectors by which an adversary might conduct attacks against the homeland. They also look at the cascading effects of an attack and other impacts resulting from infrastructure age and maintenance and from weather challenges, and they offer characterizations of various types of threat actors and vectors to raise awareness of systemic vulnerabilities and threat environments that can affect critical U.S. infrastructure.

Key Findings

  • For this report, critical infrastructure is broadly defined as systems and assets so vital to the United States that their loss would have a debilitating effect on national security, public health, or safety. The authors divide these assets into seven sectors: energy, transportation, financial services, communications, health care, water, and municipal services.
  • Impacts resulting from critical infrastructure attacks or vulnerabilities are often intensified by interdependencies and cascading effects across sectors and geographic boundaries; therefore, singular events are not really singular and will have outsize effects.
  • There is a high degree of interdependence in some sectors; the resulting difficulty in isolating the effects of an attack to a single actor or category makes attribution particularly challenging.
  • Hesitancy by private organizations to share details about specific threats or threat actors often stems from concerns regarding customer confidence, legal liabilities, or proprietary technology; this hinders information-sharing efforts, planning, response, recovery, and collaboration between affected entities and other stakeholders.
  • Infrastructure protection often requires a deep understanding of targeted infrastructure; highly trained individuals are needed to address these mitigations at the system level and work with other sector experts on cross-sector impacts.
  • Some sectors have underinvested in much-needed enhancements to infrastructure networks, assets, systems, and facilities; this increases the likelihood of disruption and interruption of services.
  • Sector authorities are often decentralized, and assets are largely privatized; resulting silos can create challenges in coordination and complicate efforts to maintain and enhance critical infrastructure.

This research was sponsored by the Office of the Director of National Intelligence and conducted within the Defense Policy Program of the RAND National Security Research Division.

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