Defection

Defection is the abandonment of one’s country, organization, or allegiance, often by joining a rival or settling elsewhere. It can involve political, military, or intelligence personnel and may carry legal and diplomatic consequences.

Political asylum: Protection granted by a state to people who have fled persecution in another country. Defectors who fear punishment at home may seek this protection in their destination country.
Oleg Gordievsky: A KGB officer who secretly worked for British intelligence and escaped from the Soviet Union in 1985. His extraction from Moscow became a prominent Cold War case of intelligence defection.
Intelligence source: A person who provides information to an intelligence service, often covertly. A defector may become a source, though defection and intelligence recruitment are distinct.
Desertion: Unauthorized abandonment of military service or duty. Desertion concerns leaving service; it becomes defection when allegiance shifts to an opposing side or country.
Diplomatic incident: An event that strains relations between states or disrupts diplomatic practice. A prominent defection can trigger disputes over asylum, custody, or the return of nationals.
Non-refoulement: A principle prohibiting the return of people to places where they face specified serious harms. It can constrain a host state's ability to send a defector back.
Viktor Belenko: A Soviet pilot who landed a MiG-25 in Japan in 1976 and sought asylum in the United States. His flight brought a highly advanced Soviet aircraft and its secrets into Western hands.
Human intelligence: Information collected from people rather than primarily from technical sensors or open publications. Defectors can provide human intelligence unavailable through surveillance or documents.
Emigration: The act of leaving one's country to live in another. Emigration can be ordinary migration without rejecting a state or transferring allegiance.
Intelligence failure: A failure to collect, interpret, or act on information needed for sound decisions. A defection can reveal that an adversary's service penetrated or misjudged an intelligence organization.

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