He is writing a history of Afghanistan after September 11, 2001 (Henry Holt). Mansur Khan Mahsud is the research coordinator for the FATA Research Center, an Islamabad-based think tank. He is from the Mahsud tribe of South Waziristan and has worked with several NGOs and news outlets as a researcher. He holds a masters degree in Pakistan studies from the University of Peshawar. Brian Fishman is a counterterrorism research fellow at the New America Foundation. This is excerpted from a longer Counterterrorism Strategy Initiative research paper on militancy in North Waziristan, part of the New America Foundation’s "Battle for Pakistan" series.