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  1. Homeland Security Investigations
  2. What We Investigate
  3. Terrorism and National Security Threats

Terrorism and National Security Threats

Terrorism and National Security Threats

HSI targets the pipelines and networks used to support and facilitate operations of terrorists and other security threats.

Terrorist organizations, adverse nations and other national security threat actors aim to disrupt our way of life and weaken our country. They conduct and support terrorist acts, espionage and other activities directed against Americans and our interests at home and abroad.

HSI plays a crucial role in the U.S. government’s effort to detect and deter these threats. We use our expansive legal authorities and expertise in global criminal investigations to target the people, money and materials that facilitate and support terrorism and other national security threats. We do this domestically and internationally, alongside our partners, to protect our country and our people.

Understanding Terrorism and National Security Threats

Broadly, national security refers to our nation’s collective defense, intelligence, internal and external security, and foreign relations capabilities. While most of HSI’s investigations involve acts committed by individuals and organizations seeking to make money from their crimes, others are driven by ideological, political, military, economic, or strategic motivations.

HSI’s national security investigations primarily involve terrorism and foreign intelligence threats.

Terrorism involves violence or the threat of violence against people or property to further a particular ideology. Terrorism can be:

  • International, meaning a foreign terrorist organization influences or directs the attacks.
    Domestic, meaning social or political objectives influence the attacks in the terrorist’s home country.

Foreign intelligence threats involve other countries collecting information to disrupt U.S. government functions, influence foreign policy, steal technology and trade secrets, and undertake other activities to harm the United States.

Terrorism and National Security Threats’ Impact

The impact of crimes targeting our national security is far-reaching and includes the following:

  • Physical harm. Terrorists do not care who they hurt or kill to achieve their goals.
  • Emotional harm. Terrorism and threats against national security greatly impact feelings of safety, turning places of entertainment, education and spirituality into potential targets.
  • Economic and public health. Foreign intelligence officers gather information on technology, military innovations and other sensitive materials. Their knowledge then threatens our security, economy, and well-being.
  • Disruption of normal life. The federal government continues to implement security measures to protect Americans from future attacks, such as changing routine travel and immigration screenings.
  • Diminishing strategic advantage. Terrorism and national security threats undercut our strategic military, political and economic standing.

HSI's Response to Terrorism and National Security Threats

Terrorists and others who threaten national security exploit legitimate trade, travel and financial systems to further their goals. HSI uses its unique authorities and expertise in these areas to stop that from happening.

HSI targets the pipelines and networks that support terrorists’ operations. We investigate the illegal movement of money that finances terrorism and prevent criminals from obtaining fraudulent identity documents that make travel easier. We also prevent our adversaries from obtaining weapons, export-controlled technology and sensitive intellectual property, and from compromising supply chain security.

HSI identifies, locates and investigates unlawfully present noncitizens in the United States who engage in these types of crimes or pose national security risks. We manage the Student and Exchange Visitor Program (SEVP), which ensures that students entering the United States to study do not threaten our national security or exploit our academic institutions.

HSI is the second-largest member of the FBI’s Joint Terrorism Task Force, which comprises members of dozens of law enforcement and intelligence agencies that pool their resources to combat terrorism. Much of our work in the national security space is conducted as part of or in coordination with the JTTF.

On the international stage, HSI leads the Visa Security Program (VSP) and the Biometric Identification Transnational Migration Alert Program (BITMAP), both of which are designed to prevent known or suspected terrorists, transnational criminals and other high-risk individuals from traveling into the United States.

The VSP deploys agents to diplomatic posts worldwide to identify and investigate visa applicants who pose potential national security threats. We share BITMAP with our foreign partners so they can use biometrics to identify and prevent terrorists from traveling through their countries and into ours.

How We Can Help Each Other

Awareness and vigilance are essential in the fight against national security threats. Here's how you can contribute:

  • Awareness. Be aware of your surroundings. Do not overshare information with people you do not know.
  • Report suspicious activities. If you see or hear something concerning, say something. Often, someone moving toward violence will change their behavior or even disclose their desire to commit a violent act. You can also contact the HSI Tip Line at 1-877-4-HSI-TIP.
Last Updated: 04/22/2024
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