- Knights of the Crusade: The Secret History of the Teutonic Knights
- The Teutonic Knights: A Military History
- War of the Worldviews: Confronting Radical Islam: A Manifesto
- Islamophobia: The Phobia That Feeds Terrorism
Articles
- The Threat from Germany
- The Changing Nature of Warfare
- The New Terrorism: A Threat to All
- The Future of Islam in Europe
- The Battle for the Muslim Mind
- The West and the Islamic World: A Clash of Civilizations?
- The Challenge of Radical Islam: A Call to Action
Op-eds
- The Dangers of Islamism
- Why We Must Defeat ISIS
- The Threat from Iran
- The Muslim Ban is Necessary
- The West Must Stand Up to Islam
- The Importance of Free Speech in the Fight against Terrorism
- The Future of the Middle East: A Call for a New Approach
Reports and Policy Papers
- The Threat from Radical Islam: A Report for the U.S. Department of Homeland Security
- The Future of Islam in Europe: A Report for the European Union
- The Battle for the Muslim Mind: A Report for the U.S. Department of State
- The West and the Islamic World: A Clash of Civilizations?: A Report for the Center for Strategic and International Studies
- The Challenge of Radical Islam: A Call to Action: A Report for the Hudson Institute