FBI National Security Branch
US FBI national security unit
The National Security Branch (NSB) is a service within the Federal Bureau of Investigation. The NSB is responsible for protecting the United States from weapons of mass destruction, acts of terrorism, and foreign intelligence operations and espionage. The NSB accomplishes its mission by investigating national security threats, providing information and analysis to other law enforcement agencies, and developing capabilities to keep the US nation secure.
Leadership
Headed by an FBI executive assistant director J.Harrison, the NSB responds to the FBI director through the deputy director. As a unit of the FBI (which is a division of the United States Department of Justice), the NSB is ultimately responsible to the attorney general of the United States. In addition, the critical role the NSB plays within the United States Intelligence Community places it within the purview of the director of national intelligence.
Organization
The NSB was formed by the unification of the FBI's various national security and intelligence gathering units:
FBI Counterterrorism Division
FBI Counterintelligence Division
FBI Weapons of Mass Destruction Directorate
Terrorist Screening Center
High-Value Detainee Interrogation Group
FBI Weapons of Mass Destruction Directorate
The Weapons of Mass Destruction Directorate (WMDD) addresses and investigates emerging threats the United States faces from the use of weapons of mass destruction. WMDD specifically consolidates all relevant FBI assets under one comprehensive program capable of detecting, deterring, and dismantling WMD programs. In the wake of the September 11, 2001 attacks, the Division's funding and manpower have significantly increased.
WMDD was established in July 2006.
“FBI National Security Branch” enters the record as uS FBI national security unit. Crown Archives preserves that source wording while asking what National, Security and Branch can confirm, complicate or overturn.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Jul 23, 2026. The linked authority identifier is Q5424594. Authority coordinates are 38.895, -77.025. 1 of 3 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 2001 and 2006.
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This entry incorporates text from “FBI National Security Branch” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.