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Research improves understanding of geographic clustering of terrorist attacks


Research improves understanding of geographic clustering of terrorist attacks

Examining the county-level correlates of terrorism in the United States

May 27, 2014Laura Walker

In a new research brief, START investigators highlight findings from their 2013 study examining whether characteristics of U.S. counties can explain the geographic clustering of terrorist attacks in the United States from 1990-2010.

Among the findings and policy considerations highlighted in the brief:

  • Attacks tended to cluster in specific areas, especially large metropolitan areas, from 1990-2010. Yet, they were also widely dispersed—each of the 48 continental U.S. states experienced at least one attack.
  • Of 581 attacks that took place from 1990 –2010, 25 percent occurred in just 10 counties:
    • New York County, NY (Manhattan) (30); Los Angeles County, CA (19); San Diego County, CA (16); Washington, D.C. (15); Miami-Dade County, FL (14); Bernalillo County, NM (13); Maricopa County, AZ (12); King County, WA (9); Lane County, OR (8); and Tulsa County, OK (8).
  • The same types of statistical data that are now routinely used by police departments to help forecast crime hot spots and deploy police officers can also be a helpful tool for those countering terrorism.
  • While the rate of terrorist attacks has declined in the past several decades, a rise in the likelihood of fatalities among recent attacks deserves continued attention.

The new research brief, “County-level Correlates of Terrorism in the United States, 1990-2010,” can be downloaded from the START website.

It is drawn from a report of the same name, “County-level Correlates of Terrorism in the United States, 1990-2010,” published by START.

This research was supported by the Resilient Systems Division of the Science and Technology Directorate of the U.S. Department of Homeland Security.  It is part of a larger effort to develop a comprehensive database on Terrorism and Extremist Violence in the U.S. (TEVUS) that integrates data from the Global Terrorism Database, the American Terrorism Study, Profiles of Perpetrators of Terrorism in the U.S., and the U.S. Extremist Crime Database. Led by the National Consortium for the Study of Terrorism and Responses to Terrorism (START), the research team is creating a resource that will allow operational and academic end-users to conduct unprecedented analyses that incorporate incident, perpetrator, and geospatial information.