Foreign internal defense

Foreign internal defense (FID) is a term used by a number of Western militaries, including the United States, France and the United Kingdom, to describe an approach to combating actual or threatened insurgency in a foreign state called the Host Nation (HN). 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 3-07.1: 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 military with outside military, diplomatic, economic, and other specialists. The most successful FID actions prevent actual violence, although that is rarely possible. When combat is needed, it is best done by HN personnel with appropriate external support, the external support preferably being in a noncombat support and training role alone.