This year, a quarter century will have passed since the Sept. 11, 2001 attacks and governments around the world recognize that the threat of extremist violence is not the same as it once was in terms of the most hostile actors, their motivations, and the ways in which they interact with the information environment. In short, the threat is evolving — and in some respects, growing.  

Since early 2025, Just Security’s Counterextremism Initiative has explored this persistent threat in a series of essays authored by a diverse group of experts and researchers. While the international community has failed to reach a consensus on the meaning of terms such as violent extremism and terrorism (and nations have adopted multiple definitions of these labels), for the purposes of this series, violent extremism is broadly defined as a willingness to use or support violence in furtherance of political, religious, or ideological goals. Terrorism is also broadly defined as “the intimidation or coercion of populations or governments” by non-state actors “through the threat or perpetration of violence, causing death, serious injury or the taking of hostages.” Terrorism is considered one manifestation of violent extremism, which includes other forms of violence as well. 

 Just Security’s Counterextremism Initiative seeks to:

(1) Define and analyze emerging forms of violent extremism, taking into account the digital era

(2) Assess how persistent threats continue to adapt

(3) Explore the phenomenon of radicalization, including how non-violent forms of extremism lead some down a darker path, as well as the growing role played by young adults and minors in extremist violence

(4) Examine the intersection of violent extremism with misogyny, racism, and other forms of hatred

(5) Evaluate how the United States, its allies and partners, and other governments are responding to this ever-changing landscape.

Below, Just Security presents a collection of more than two dozen contributions on these topics. This collection will grow in the months to come, as we continue to provide new perspectives and proposed solutions.

• Tom Joscelyn, Eleven Precedents of ISIS-Inspired Vehicle Rammings: Precursors to New Orleans Attack (Jan. 4, 2025)
• Jacob Ware, Nihilistic Violent Extremism: A Valuable Stride Forward in American Counterterrorism (May 21, 2025)
• Cathy Buerger, Unequal Before the Law: How Trump’s Death Penalty Order Codifies Dangerous Speech (June 6, 2025)
• Khusrav Gaibulloev, James Piazza and Todd Sandler, Terrorism and the Threat of Weak States (June 10, 2025)
• Rachel Levinson-Waldman and Melanie Geller, How DHS’s New Social Media Vetting Policies Threaten Free Speech (June 17, 2025)
• Sam Jones and Roudabeh Kishi, After the Minnesota Attacks: How Communities Can Respond to the Climate of Hostility Facing Public Officials (June 18, 2025)
• Mackenzie Harms, Ideology Matters: An Analysis of Sentencing in Terrorism and Extremism Cases (June 25, 2025)
• Steven Rai and Cody Zoschak, Setting the Record Straight on Nihilistic Violence (July 1, 2025)
• Olof Blomqvist, The Taliban’s Slow Dismantling of Afghan Media (July 10, 2025)
• Jason M. Blazakis, Understanding the Trump Administration’s Delisting of Hay’at Tahrir al-Sham (July 18, 2025)
• Tanmay Durani, Vague By Design? The Oversight Board, Meta’s DOI Policy, and the Kolovrat Symbol Decision (July 29, 2025)
• Luke Baumgartner, It’s Time to Designate The Base as an FTO (Aug. 5, 2025)
• Niamatullah Ibrahimi, The Experience of Time and Tyranny Under the Taliban in Afghanistan (Sept. 2, 2025)
• Cynthia Miller-Idriss, How Misogyny Fuels Violent Extremism (Sept. 16, 2025)
• Tom Joscelyn interview with Cynthia Miller-Idriss, The Just Security Podcast: Misogyny’s Role in Violent Extremism (Sept. 18, 2025)
• Cathy Buerger, Repression as Rescue: The Authoritarian Logic of Trump’s Early Executive Orders (Sept. 25, 2025)
• Bruce Hoffman and Jacob Ware, Assassinations in America: How Political Violence Became Personal (Oct. 1, 2025)
• Bettina Rottweiler, Caitlin Clemmow, Austin Doctor and Brenna Helm, Children, Young People and the Emerging Terrorism Threat Landscape (Sept. 26, 2025)
• Mackenzie Harms, Swatting Attacks and Nihilistic Violent Extremism: A Primer (Oct. 7, 2025)
• Thomas E. Brzozowski, A New Approach in the Fight Against Transnational Violent Extremism is Needed (Oct. 8, 2025)
• Michael Jensen and Amy Cooter, Correctly Assessing Left-Wing Terrorism and Violence in the United States (Oct. 21, 2025)
• Thomas E. Brzozowski, How Designating Antifa as a Foreign Terrorist Organization Could Threaten Civil Liberties (Oct. 27, 2025)
• Mariana Olaizola Rosenblat, The Feedback Loop Between Online Extremism and Acts of Violence (Nov. 10, 2025)
• Tom Joscelyn interview with Thomas E. Brzozowski, The Just Security Podcast: Examining the Trump Administration’s New Antifa Designations (Nov. 17, 2025)
• Tom Joscelyn, State Dept’s Foreign Terrorist Designations Undermine Claims of “Antifa” Threat (Nov. 19, 2025)
• Luke Baumgartner, How the DOJ is Prosecuting Nihilistic Violent Extremism as Domestic Terrorism (Dec. 9, 2025)
• Tom Joscelyn and Ryan Goodman, The Smearing of Alex Pretti and NSPM-7 (Jan. 26, 2026)
• David Sterman, Is the U.S. Conducting Air Strikes Against Al Qaeda in Yemen? (Feb. 12, 2026)
• Thomas E. Brzozowski, How a Broadly Defined Counterterrorism Statute Could Be Abused, (March 3, 2026)
• David Scharia, Global Governance of Emerging Technologies: Counterterrorism Challenges at the United Nations Security Council (April 3, 2026)
• Mary B. McCord, How the Domestic Terrorist Label Endangers Rights and Drives Extremist Violence (May 21, 2026)