Unconventional warfare (United States Department of Defense doctrine)

In United States doctrine, unconventional warfare (abbreviated UW) is the term for guerrilla warfare that is conducted or supported by units in the United States Special Operations Command. Guerrilla warfare is one aspect of the broader term insurgency. The American definition of UW is:

Unconventional Warfare consists of activities conducted to enable a resistance movement or insurgency to coerce, disrupt or overthrow an occupying power or government by operating through or with an underground, auxiliary or guerrilla force in a denied area."

UW was the first mission assigned to United States Army Special Forces when they were formed in 1952; they now have additional missions, including foreign internal defense (FID). In the United States, "special forces" refers specifically to the United States Army Special Forces (SF), as opposed to the usage in most other countries, where "special forces" refers to the range of unit types that the U.S. calls "special operations forces" controlled by the United States Special Operations Command (USSOCOM). SF units are tasked with seven primary missions:

SF may be given other missions including warfare and support, combat search and rescue (CSAR), security assistance, peacekeeping, humanitarian assistance, humanitarian demining and counter-drug operations; other USSOCOM units or other U.S. government activities may be the specialists in these secondary areas

The UW mission assumes that U.S. forces will work with troops in another country and possibly with other allies; UW is always multinational. Depending on the particular situation, their role may be from pure training all the way to leading a joint force in combat. Over more than fifty years, roles and missions have continued to evolve, based on the history of operations.

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