What Is Terrorism?

 Terrorists have sought to achieve their political agendas all over the world.

Video video 4:25

What the World’s Terrorist Groups Have in Common

Strong ideology motivates those who commit terrorism, no matter their goals.

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Who Counts As a Terrorist?

From foreign groups to domestic threats, how does the U.S. government define terrorism?

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Terrorism by the Numbers

What the numbers behind terrorism—and the process of getting to them—reveal.

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Radicalization and Right-Wing Extremism

Learn how the domestic terror threat has evolved since 9/11.

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Terrorism and the Media

Terrorism is often described as requiring the “oxygen of publicity.”

Video video 3:30

U.S. Counterterrorism Since 1945

The history of counterterrorism in the United States is more than a list of policies. It shows how the definition of terrorism and the agencies and tools used to pursue those who commit it have evolved over time.

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Tools of Counterterrorism

National security experts have a range of options available as they work to prevent terrorism.

Video video 2:45

How a Single Phrase Defined the War on Terror

The open-ended scope of the 2001 Authorization for Use of Military Force has justified counterterrorism policy for two decades—and counting.

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The Terrorist Money Trail

What the challenges of targeting terrorists’ finances tell us about the evolving terrorist threat.

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Terrorism Module Assessment

Questions to check your understanding.

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