"How did Muhajiroun become Jihadists? Foreign Fighters and the Geopolitics of the Conflict in Syria," in Jasmine K. Gani and Raymond Hinnebusch, eds., Actors and Dynamics in the Syrian Conflict's Middle Phase: Between Contentious Politics, Militarization and Regime Resilience (St. Andrews Syrian Studies), Routledge, 2022 (with Yutaka Takaoka).
"Strategic Asset or Political Burden? U.S. Military Bases and Base Politics in Saudi Arabia," in Shinji Kawana and Minori Takahashi, eds., Exploring Base Politics: How Host Countries Shape the Network of U.S. Overseas Bases (Routledge Advances in International Relations and Global Politics), Routledge, 2020.