The National Security Agency (NSA), Central Intelligence Agency (CIA) and Federal Bureau of Investigation (FBI) are agencies of the American government that are concerned with security, intelligence, and law enforcement respectively. Each agency has a specific area of focus, although they do occasionally cooperate on cases to share information which could lead to a breakthrough. The staff of each agency are highly trained specialists in their field, and people interested in pursuing careers at these agencies usually attend top tier schools.
The CIA gathers information internationally which is relevant to American security. The CIA also has the ability to evaluate the information and take action if the information suggests that the United States may be at risk. The CIA operates around the world, using a series of agents on the ground to relay information back to the central offices in Virginia. CIA agents often cooperate with other international intelligence agencies, especially wartime allies. If terrorists are planning an attack on the American government from outside the United States, for example, the investigation would be handled by the CIA.
The FBI is a domestic law enforcement agency. The FBI also gathers domestic intelligence, and works to put a stop to threats from within the United States. As the premier law enforcement agency in the United States, the FBI assists local police in handling major cases, and also has a sophisticated evidence lab. Law enforcement agencies can send material for analysis to the FBI if their local labs are not equipped to handle it. Major murder cases, crimes which cross state boundaries, and kidnappings are all under the jurisdiction of the FBI. If someone within the United States was planning to do something that threatened American security, it would be under the jurisdiction of the FBI.
The FBI also handles domestic surveillance. If the CIA wants information on individuals within the United States, they must go through the FBI to obtain it. The FBI maintains federal watchlists, most wanted documentation, and surveillance services on suspicious individuals inside the United States. FBI agents are distributed around the country in local bureaus to assist local law enforcement in enforcing the laws of the United States and to neutralize threats to American security.
The NSA is probably the least known and most poorly understood government intelligence agency. The NSA is actually combined with the Central Security Service (CSS), and it is primarily a cryptological organization. NSA employees decrypt foreign intelligence, generate encryption keys to secure American information, and handle data processing for the United States government. The mission of the NSA is “information assurance.” Information assurance refers to breaking foreign intelligence codes while retaining the security of American information, which is accomplished through encryption, secured computer systems, and access control.
The NSA handles most American computer intelligence and decryption, and has also contributed significantly to computer technology around the world. Early computers were developed in the offices of the NSA, and the NSA continues to innovate in the technological field. NSA agents are primarily found in the head offices of the organization in Maryland, although they also work closely with the United States Armed Forces to secure military information on bases and in the battlefield.