The threat of terrorism, which created the vogue for a national ‘‘homeland security’’ infrastructure, must be understood in a strategic context. Terrorist attacks have direct costs, but they also seek self-injurious overreaction, such as the waste of blood and treasure on the part of the victim state; recruitment and sympathy gains when the victim state misdirects a violent response; and the weakening of the political order in the society attacked so that it is induced to act wrongly. When it does so, it cedes the moral and ideological high ground, making terrorists groups look relatively more legitimate.

Policymakers should use risk management to prioritize security efforts, and they should avoid holding out the promise of perfect security, as there is no such thing. Civil liberties must be fully protected, and doing so is consistent with proportionate and well-focused domestic security efforts.

More on Counterterrorism and Homeland Security


What Happened to the Islamic State Foreign Fighters That Had Returned to Europe?

By John Mueller. National Interest (Online). November 5, 2018.

Another Year of the War in Afghanistan

By A. Trevor Thrall and Erik Goepner. Texas National Security Review. September 11, 2018.

U.S. Security Aid Enables Torture in Cameroon

By A. Trevor Thrall and Jordan Cohen. UPI. August 14, 2018.

Cato Studies

Extreme Vetting of Immigrants: Estimating Terrorism Vetting Failures

By David Bier. Policy Analysis No. 838. April 17, 2018.

Public Opinion and Counterterrorism Policy

By John Mueller and Mark G. Stewart. White Paper. February 20, 2018.

Step Back: Lessons for U.S. Foreign Policy from the Failed War on Terror

By A. Trevor Thrall and Erik Goepner. Policy Analysis No. 814. June 26, 2017.


Trump’s National Security Strategy: A Critic’s Dream

Emma Ashford. Texas National Security Review. December 21, 2017.

Review of Kilcullen, David, Blood Year: The Unraveling of Western Counterterrorism

Sahar Khan. H-War. November 2017.

The Danger of Overreacting to Terrorism—and How to Resist It

Benjamin H. Friedman. World Politics Review. August 15, 2016.

Public Filings

Reducing Wasteful Federal Spending

By Chris Edwards. Testimony. June 10, 2015.

Hearing on “Continued Oversight of U.S. Government Surveillance Authorities”

By Julian Sanchez. Testimony. December 11, 2013.

Notice of Proposed Rulemaking: Passenger Screening Using Advanced Imaging Technology

By Jim Harper, John Mueller, and Mark G. Stewart. Public Comments. June 21, 2013.

Cato Reviews & Journals

Oppose Any Foe: The Rise of America’s Special Operations Forces by Mark Moyar

Brad Stapleton. Cato Journal. Winter 2018.

Trump Takes ‘A Pause ’

Marni Soupcoff. Regulation. Spring 2017.

76. Nuclear Weapons: Proliferation and Terrorism

Cato Handbook for Policymakers. Cato Handbook for Policymakers, 8th Edition (2017).


Double Game: Why Pakistan Supports Militants and Resists U.S. Pressure to Stop

Featuring Sahar Khan, Ambassador Robin L. Raphel, and John Glaser. September 27, 2018. Policy Forum.

The NSA and the Road to 9/11: Lessons Learned and Unlearned

Featuring William Binney, J. Kirk Wiebe, Edward Loomis, Thomas Drake, Diane Roark, & Patrick G. Eddington. September 4, 2018. Policy Forum.

Live Power Problems Podcast Recording: “All I Want for Christmas is an F-35: Trump, the Generals and the Defense Budget”

Featuring Aaron Mehta, Emma Ashford, and A. Trevor Thrall. December 12, 2017. Cato Digital.


Remarks at Cato Institute Conference on Terrorism

By David B. Kopel. September 10, 1996.

Downsizing the Federal Government