All states gather intelligence about the ‘enemies of the state’ at home and abroad. The police and armed forces collect and act on intelligence, but the term intelligence services refers to services organized expressly for the collection of secret information. Such services also take covert (disavowable) activity on behalf of the state.
In Britain there are two such organizations, the Secret Intelligence Service (MI6), which is supposed only to operate abroad, and the Intelligence Service (MI5) which operates at home. They engage both in the collection of intelligence and in counter-intelligence—that is, in combating the activities of others, especially other intelligence services, working against British interests. The evidence, much of it necessarily non-verifiable, is that the organizations devoted much energy into watching each other and that both were heavily penetrated by the very organization—namely, the Soviet intelligence service, the KGB—that they were supposed to be fighting. The existence and operations of both services raise problems of ministerial control and accountability to democratic or parliamentary procedures. Another general area of concern has been the extent of collaboration between intelligence services behind the backs of governments.
In the United States the Federal Bureau of Investigation (FBI) (domestic) and the Central Intelligence Agency (CIA) (overseas) play roles similar to the two British services, though they have always been much more open and, at least in theory, subject to democratic accountability. In the Soviet Union the KGB, the descendant of a series of intelligence organizations dating back to Tsarist times, was responsible for both domestic and external intelligence, and for a system of labour camps and prisons (the ‘Gulag’). Other intelligence services which have attracted widespread interest include the French DGSE (Direction Générale de la Sécurité Extérieure) and the Israeli Mossad (external) and Shin Bet (internal).
— Peter Byrd
