Warfare, Irregular Threats, and Terrorism Program

The Warfare, Irregular Threats, and Terrorism Program (WITT) focuses on the activities and capabilities of countries like China, Russia, and Iran as well as the threat and evolution of paramilitary groups and terrorist networks

Led by Dr. Daniel Byman, the Warfare, Irregular Threats, and Terrorism Program (formerly known as the Transnational Threats Project) conducts research and analysis on irregular and hybrid warfare, terrorism, and military operations. The program examines Chinese, Russian, and Iranian irregular and hybrid warfare activities, such as covert action, economic warfare, support to non-state partners, cyber operations, disinformation, political warfare, and espionage. It also assesses terrorist and paramilitary activities by such organizations as Lebanese Hezbollah, Shia militias, the Houthi movement (or Ansar Allah), the Islamic State, al Qaeda, and far-right and far-left extremist networks. Finally, the program researches the military capabilities of China, Russia, and other U.S. adversaries and examines how the United States and its allies can best respond.

The Warfare, Irregular Threats, and Terrorism Program conducts fieldwork overseas, builds and analyzes data sets, and utilizes satellite imagery and other types of qualitative and quantitative analysis. It also draws from an extensive network of policy experts from the U.S. and partner governments, Congress, academia, nongovernmental organizations (NGOs), and the private sector. In partnership with CSIS’s Andreas C. Dracopoulos iDeas Lab, the program translates its research into high-quality videos, podcasts, reports, visualizations, and other products designed to engage audiences and inform policy discussions through objective analysis. The Warfare, Irregular Threats, and Terrorism Program's work is highly valued by government officials, corporate executives, and other influential leaders seeking to understand, prevent, and counter transnational threats.

Contact Information

Media Queries

Featured Analysis

Photo: Anwar Amro/AFP/Getty Images

The Coming Conflict with Hezbollah

Since October 7, 2023, there have been over 4,400 attacks by Israel and Hezbollah combined, and the risk of war is high. Hezbollah has also repeatedly violated UN Security Council Resolution 1701 by deploying forces and firing weapons against Israel.

View CSIS Brief

Latest Analysis

All Warfare, Irregular Threats, and Terrorism Program Content

Filter by

1 - 10 of 263 results

Improving U.S. Intelligence Sharing with Allies and Partners

As the U.S. prepares to compete with China and other adversaries, intelligence sharing with key partners will be vital. In practice, however, intelligence sharing is beset with difficulties, including limited trust, poor bureaucratic procedures, and under-resourcing.

Report by Daniel Byman — January 28, 2025

Deterring Russia: U.S. Military Posture in Europe

Russia’s war in Ukraine and subversive activities in Europe pose a long-term security challenge. While the United States must press its allies to increase defense spending, it should also maintain a resilient—and sustainable—presence in Europe to deter Russian aggression.

Brief by Seth G. Jones and Seamus P. Daniels — January 27, 2025

Jihadist Terrorism in the United States

Despite the attack in New Orleans, long-term trends suggest that jihadist terrorism in the U.S. is not resurgent. The number of jihadist plots and attacks in the U.S. has been low and the average lethality of attacks has also fallen since the territorial defeat of ISIS. 

Brief by Alexander Palmer, Skyeler Jackson, and Daniel Byman — January 21, 2025