Foreign Internal Defense

Foreign internal defense (FID) is a term by the militaries of some countries, including the United States, France, and the United Kingdom, to describe an integrated and synchronized, multi-disciplinary (and often joint, interagency, and international as well) approach to combating actual or threatened insurgency in a foreign state. This foreign state is known as the Host Nation (HN) under US (and generally accepted NATO) doctrine. The term counter-insurgency is more commonly used worldwide than FID. FID involves military deployment of counter-insurgency specialists. According to the US doctrinal manual, Joint Publication 3-22: Foreign Internal Defense (FID), those specialists preferably do not themselves fight the insurgents. Doctrine calls for a close working relationship between the HN government and security forces with outside diplomatic, information, intelligence, military, economic, and other specialists. The most successful FID actions suppress actual violence; when combat operations are needed, HN security forces take the lead, with appropriate external support, the external support preferably being in a noncombat support and training role alone.

Formally, FID is defined as, "Participation by civilian and military agencies of a government in any of the action programs taken by another government or other designated organization to free and protect its society from subversion, lawlessness, and insurgency."

The FID effort is a multinational and interagency effort, requiring integration and synchronization of all instruments of national power.

The military instrument of national power supports other instruments of national power (generally including also: diplomatic, information/intelligence, economic) to protect and enhance national security interests and deter conflict using a wide range of actions, including:

Within this range of military operations, nation assistance (NA) is civil or military assistance (other than foreign humanitarian assistance [FHA]) rendered to a nation by US forces within that nation's territory during peacetime, crises or emergencies, or war, based on agreements mutually concluded between the United States and that nation. Nation assistance operations support the HN by promoting sustainable development and growth of responsive institutions. The goal is to promote long-term regional stability. Nation assistance programs include:

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