Ulster Defense Association/Ulster Freedom Fighters (UDA/UVF)

Ultra, Operation

Underground Facilities, Geologic and Structural Considerations in the Construction

Undersea Espionage: Nuclear vs. Fast Attack Subs

Unexploded Ordnance and Mines

United Kingdom, Counter-Terrorism Policy

United Kingdom, Intelligence and Security

United Nations Security Council

United Self-Defense Forces/Group of Colombia (AUC Autodefensas Unidas De Colombia)

United States, Counter-Terrorism Policy

United States, Intelligence and Security

United States Intelligence, History

Unmanned Aerial Vehicles (UAVs)

Uranium

Uranium Depletion Weapons

USAMRICD (United States Army Medical Research Institute of Chemical Defense)

USAMRIID (United States Army Medical Research Institute of Infectious Diseases)

USS Cole

USS Liberty

USSTRATCOM (United States Strategic Command)

Vaccination

Vaccines

Variola Virus

Venezuela, Intelligence and Security

Venona

Vietnam War

Viral Biology

Viral Exposure Therapy, Antiviral Drug Development

Voice Alteration, Electronic

Voice of America (VOA), United States