Revolutionary Proletarian Initiative Nuclei (NIPR)

Revolutionary Proletarian Initiative Nuclei (NIPR) is a clandestine leftist extremist group that appeared in Rome in 2000. NIPR adopted the logo of the Red Brigades of the 1970s and 1980s—an encircled five-point star—for their declarations.

Revolutionary United Front (RUF)

Revolutionary United Front (RUF) is a loosely organized guerrilla force seeking to retain control of the lucrative diamond-producing regions of Sierra Leone. The group funds itself largely through the extraction and sale of diamonds obtained in areas of Sierra Leone that it controls.

Revolutionary War, Espionage and Intelligence

The American Revolution officially began with the signing of the Declaration of Independence on July 4, 1776. However, the conflict between Britain and the American colonies escalated to full-scale war from several orchestrated acts of subversion against British authority.

RF Detection

Among the most potentially damaging weapons of electromagnetic warfare are RF, or radio frequency systems. Also known as directed-energy weapons, these use electromagnetic energy on specific frequencies to disable electronic systems.


Ricin is a highly toxic protein that is derived from the bean of the castor plant (Ricinus communis). The toxin causes cell death by inactivating ribosomes, which are responsible for protein synthesis.

Robotic Vehicles

From the late 1980s onward, robotic vehicles have become an increasingly important component of security operations and related activities. They can be used to gather information in areas where a human could not safely go and undertake tasks a human could not safely perform.

Romania, Intelligence and Security

A former Soviet bloc country, Romania is struggling to rebuild its national government and economy following the collapse of Soviet communism. Romania further struggled to free its government of authoritarian influences.

Room 40

Advances in communications technology such as the telephone and trans-Atlantic telegraph prompted the development of increasingly sophisticated cipher systems and codes. The telegraph facilitated communication between command and remote forces, but the lines were vulnerable to tapping, the interception of message traffic, on the wires.

Rosenberg (Ethel and Julius) Espionage Case

Julius and Ethel Rosenberg were a couple accused in 1950 by the United States government of operating a Soviet spy network and giving the Soviet Union plans for the atomic bomb. During a time of tense scrutiny over alleged communist infiltration of the American government, the trial of the Rosenbergs became the center of a political storm over communist influence in America.

Russia, Intelligence and Security

The Russian Empire dominated Eastern Europe and Western Asia from the Middle Ages through the nineteenth century. However, the devastation caused by World War I plunged the nation into revolution in 1917, leading to an overthrow of the Czarist regime and the birth of communism.

Russian Nuclear Materials, Security Issues

The breakup of the former Soviet Union in 1991 raised fears about the disposition and security of that nation's nuclear materials, including its strategic and tactical nuclear weapons. Of more immediate concern is the security of Soviet stores of plutonium and enriched uranium, which could be used to make either nuclear weapons or "radiological dispersal devices" (RDDs), or "dirty bombs"— conventional explosives that would spew radioactive debris packed around them over a wide area.


Sabotage is a deliberate act of destruction or work stoppage intended to undermine the activities of a larger entity, whether it is a business, government, or some other organization. The practice of sabotage, which has roots in the labor movements of the late nineteenth and early twentieth centuries, gained military and political application during the world wars and thereafter.

Salafist Group for Call and Combat (GSPC)

The Salafist Group for Call and Combat (GSPC) splinter faction that began in 1996 has eclipsed the Groupe Islamique Armé (GIA or Armed Islamic Group). since approximately 1998, and currently is assessed to be the most effective remaining armed group inside Algeria.

Salmonella and Salmonella Food Poisoning

Salmonella is the name of a group, or genus, of bacteria that live in the intestinal tract of warm-blooded animals, including humans, as well as in cold-blooded animals such as turtles. The name of the microbe comes from its discoverer.

Sandia National Laboratories

Founded in 1949, Sandia National Laboratories, located in New Mexico (with additional laboratory facilities in California and Hawaii), is a government-owned facility managed by Lockheed Martin corporation for the Department of Energy (DOE). Sandia was originally managed by AT&T, but in 1993 Lockheed Martin assumed managerial control.

Sarin Gas

Sarin gas (O-Isopropyl methylphosphonofluoridate), also called GB, is one of the most dangerous and toxic chemicals known. It belongs to a class of chemical weapons known as nerve agents, all of which are organophosphates.

Satellite Technology Exports to the People's Republic of China (PRC)

The issue of satellite technology exports from the United States to the People's Republic of China (PRC) mirrored larger concerns over Chinese espionage that surfaced in the late 1990s. In the case of satellite technology sales, however, United States companies and even some sectors of the federal government favored at least some degree of technology transfer, if only to maintain good relations between the two countries.

Satellites, Non-Governmental High Resolution

Satellite imagery at resolutions useful for military and intelligence purposes has historically been available only from satellites developed, launched, and operated by governments. As a result, access to and dissemination of the high-resolution satellite images was tightly controlled in the interest of national security.

Satellites, Spy

Spy satellites are robotic observational platforms that orbit the Earth in order to image its surface and to record radio signals for military and political purposes. They transmit their data to Earth, where it is interpreted by specialists in centralized, secretive facilities such as the U.S.

Saudi Arabia, Intelligence and Security

The Middle East is the seat of some of the world's most ancient civilizations and ethnic groups. Ancient Persia (Iran) and Byzantium (Turkey), in different eras, both claimed the land corresponding to present-day Saudi Arabia.

Scanning Technologies

X rays are electromagnetic waves in the 10-8 to 10-11 meter (3 × 1016 to 3 × 1019 Hz) range of the spectrum. (Alternatively, x rays can, like all electromagnetic waves, be conceived of as particles termed "photons.") Because x rays have more energy than visible light, they can pass through solid objects that are otherwise opaque.

SEAL Teams

Ranking among the most elite fighting forces in the world, United States Navy SEALs (Sea, Air, Land) operate in teams designed to wage unconventional warfare, particularly in a water environment. The SEAL team concept has its roots in World War II, though actual SEAL teams were not commissioned until 1962.

Secret Service, United States

The United States Secret Service (USSS) has two missions that, while sharply distinguished from one another, are united by the principle of protection. On the one hand, in its more visible role, the service provides protection of the president, vice president, and other dignitaries and their families.

Secret Writing

Secret writing is any means of written communication whereby a spy conceals the actual written text, whether it is enciphered/encoded or not. Codes and ciphers are sometimes mistakenly placed under the heading of "secret writing," but this is accurate only if that expression is taken in its most general sense, as writings that are concealed in any way.

Security Clearance Investigations

A security clearance is a limited license or initial general permission to access classified information—that is, any data or material belonging to the federal government that relates to sensitive topics such as military plans or vulnerabilities of security systems. Authorization for a security clearance is far from automatic, but rather requires extensive background checks and investigations.

Security, Infrastructure Protection, and Counterterrorism, United States National Coordinator

The U.S. National Coordinator for Security, Infrastructure Protection, and Counterterrorism is a broadly based office created by Presidential Decision Directive (PDD) 62.

Security Policy Board, United States

An advisory committee created by President William J. Clinton in 1994, the Security Policy Board (SPB) reported to the president through the National Security Advisor on matters of security policy.


A seismograph is an instrument that measures and records elastic ground vibrations called seismic waves that are generated by earthquakes and man-made explosions. By recording the arrival of seismic waves at remote seismograph stations, seismologists deduce information about the initial earthquake fault rupture or explosion, and about the physical properties of earth materials between the seismic source and the seismograph.

Seismology for Monitoring Explosions

Seismology has been an important tool for the remote detection of large explosions, especially underground nuclear tests, for many years and is expected to play an important role in Comprehensive Test Ban Treaty verification. The treaty was signed by President Clinton and other world leaders in 1996, and was subsequently ratified by the United States Congress in 1999.

Senate Select Committee on Intelligence, United States

Established in the wake of congressional investigations regarding activities of United States intelligence services in the 1970s, the Senate Select Committee on Intelligence (SSCI) is, along with the House Permanent Select Committee on Intelligence, the principal means by which Congress oversees the intelligence community. In addition to reviewing, studying, and reporting on intelligence activities and programs, the SSCI is responsible for submitting to the Senate appropriate proposals for legislation.