Books and Monographs

2016. Foundations of the Islamic State: Management, Money, and Terror in Iraq, 2005-2010 (with J. Shapiro, H. Shatz, et al.), Santa Monica, CA: Rand Corporation

2016. U.S. Special Operations Forces in the Philippines, 2001-2014 (with L. Robinson and G. Oak), Santa Monica, CA: Rand Corporation.

2014. Countering Others' Insurgencies: Understanding U.S. Small-Footprint Interventions in Local Context (with S. Watts, J. Campbell, S. Lalwani, and S. Bana), Santa Monica, CA: Rand Corporation. (Summary here.)


2016. The Impact of U.S. Drone Strikes on Terrorism in Pakistan (with A. Sarbahi) International Studies Quarterly.

2016. Conditional Cash Transfers, Civil Conflict and Insurgent Influence: Experimental Evidence from the Philippines (with B. Crost and J. Felter), Journal of Development Economics 118(1):171-182.

2014. Aid Under Fire: Development Projects and Civil Conflict (with B. Crost and J. Felter), American Economic Review 104(6): 1833-1856.

2013. Insurgent Compensation: Evidence from Iraq (with B. Bahney, R. Iyengar, D. Jung, J. Shapiro, and H. Shatz), American Economic Review 103(3): 518-522.

2013. The Future of Insurgency (with S.G. Jones). Studies in Conflict & Terrorism 36(1): 1-25.

2012. Does Decapitation Work? Assessing the Effectiveness of Leadership Targeting in Counterinsurgency Campaigns. International Security 36(4): 47-79. Appendix. Errata.

2008. The Geography of Insurgent Organization and its Consequences for Civil Wars: Evidence from Liberia and Sierra Leone. Security Studies17(1): 107-237.

2007. Negotiated Settlements and Government Strategy in Civil Wars: Evidence from Darfur. Civil Wars 9 (4): 359-377.

2007. International Norms, Commerce, and the Political Economy of Insecurity in Sierra Leone. Canadian Journal of African Studies 41(1): 66-94.

2004. Timber Booms, State Busts: The Political Economy of Liberian Timber. Review of African Political Economy 101: 441-456.

Book Chapters

2014. Security Implications of Drones in Warfare, in D. Cortright, K. Wall and R. Fairhurst, eds., Drones and the Future of Armed Conflict: Ethical, Legal, Strategic Implications (Chicago: University of Chicago Press).

2013. Timber Booms, State Busts: The Political Economy of Liberian Timber, in Rita Abrahamsen, ed., Conflict and Security in Africa (Suffolk, U.K.: James Currey Press), 25-40.

Working Papers

Explaining Al Qa’ida’s Involvement in Insurgencies (with S.G. Jones). December 2013.

Abstract: Since al Qa’ida was established in 1988, it has participated in 29 percent of the total conflicts involving Sunni insurgent groups. This study examines why al Qa’ida intervenes in some insurgencies, but not others, and why it allies with some Sunni groups, but not others, when it becomes involved in an insurgency. It analyzes 86 Sunni insurgencies since al Qa’ida was formed, identifying key factors associated with al Qa’ida alliances. It tests several hypotheses by conducting a statistical analysis using the universe of cases of Sunni insurgencies from 1989-2012, as well as a case study of al Qa’ida’s alliance behavior in Iraq after the U.S. invasion in 2003. Both the quantitative and qualitative evidence indicate that ideology and social networks—often developed and reinforced in jihadist training camps—provide the most persuasive explanations: al Qa’ida is most likely to intervene in support of insurgencies where there is a Sunni group that espouses a radical Salafi-jihadist ideology and has leaders who underwent training in an al Qa'ida camp.

Explaining the Duration of Counterinsurgency Campaigns (with B. Urlacher) February 2012

Abstract: Why are some counterinsurgency campaigns resolved quickly while others go on for decades? Numerous studies examine the duration of civil and interstate wars but few examine insurgency as distinct type of war. Using a new dataset of counterinsurgency wars between 1800-2000, we find (1) that the duration of insurgencies has varied substantially over time and (2) that the effects of several key factors have varied across different eras. These results are consistent with the hypothesis that changes in the international system have had a strong impact on insurgency as a type of warfare.

Op-Eds, Policy Briefs, Commentary

After the Battle for Mosul, Get Ready for the Islamic State to Go Underground," War on the Rocks, October 18, 2016 (with P. Ryan).

Striking Back at The Islamic State’s Foreign Fighter Pipeline, The National Interest, May 31, 2016 (with Benjamin Bahney and Howard J. Shatz).

The Islamic State's Money Problems, USA Today, March 4, 2016.

To Defeat ISIS, Focus on Its Real Sources of Strength, The National Interest, December 4, 2015 (with Benjamin Bahney).

The Enemy You Know and the Ally You Don't, Foreign Policy, June 23, 2015 (with Benjamin Bahney and Patrick Ryan).

Who Runs the Islamic State? US News & World Report, May 22, 2015 (with Benjamin Bahney).

Terrorist Financing in Canada and Abroad, Testimony presented before the Canadian Parliament House of Commons Standing Committee on Finance, May 5, 2015.

Countering ISIL's Financing, Testimony presented before the House Financial Services Committee on November 13, 2014

Hit the Islamic State in the Pocketbook, Newsday, October 5, 2014 (with Benjamin Bahney).

Hitting ISIS Where It Hurts: Disrupt ISIS' Cash Flow in Iraq, The New York Times, August 13,2014. (with Benjamin Bahney).

Obama's Iraq Dilemma: Where did ISIS come from, and can anything be done about it?, US News & World Report, June 17, 2014.

Partner Capacity in Counterinsurgency Campaigns, Research Brief, RAND Corporation, February 2014.

Prospects for a 'Rule Book' on Targeted Killing, RAND Corporation, December 5, 2012.

Do Targeted Killings Work? Council on Foreign Relations, September 24, 2012. (Reprinted on The RAND Blog, August 22, 2012.)

Drone Strikes Keep Pressure on al-Qaida, Providence Journal, August 18, 2012. (Reprinted by RAND Corporation, August 22, 2012.)

The Effectiveness of Leadership Decapitation in Combating Insurgencies, Policy Brief, Belfer Center for Science and International Affairs, June 2012.