Unconventional warfare (UW) is the support of a foreign insurgency or resistance movement against its government or an occupying power. Whereas conventional warfare is used to reduce the opponent's military capability directly through attacks and maneuvers, unconventional warfare is an attempt to achieve victory indirectly through a proxy force. UW contrasts with conventional warfare in that forces are often covert or not well-defined and it relies heavily on subversion and guerrilla warfare.
As with all forms of warfare, the general objective of unconventional warfare is to instill a belief that peace and security are not possible without compromise or concession. Two original definitions are claiming: "The intent of U.S. Unconventional Warfare efforts is to exploit a hostile power’s political, military, economic, and psychological vulnerabilities by developing and sustaining resistance forces to accomplish U.S. strategic objectives." or according to John F. Kennedy: "There is another type of warfare—new in its intensity, ancient in its origin—war by guerrillas, subversives, insurgents, assassins; war by ambush instead of by combat, by infiltration instead of aggression, seeking victory by eroding and exhausting the enemy instead of engaging him. It preys on unrest."
Unconventional warfare can be employed in furtherance of one of three strategic outcomes: Overthrow of an existing government or occupying power, disruption of the operations of that power, or the coercion of that power.
Methods and organizationEdit
Unconventional warfare targets civilian population psychologically to win hearts and minds, and only targets military and political bodies for that purpose, seeking to render the military proficiency of the enemy irrelevant. Limited conventional warfare tactics can be used unconventionally to demonstrate might and power, rather than to substantially reduce the enemy's ability to fight. In addition to the surgical application of traditional weapons, other armaments that specifically target military can be used are: airstrikes, nuclear weapons, incendiary devices, or other such weapons.
Special Forces, inserted deep behind enemy lines, are used unconventionally to train, equip, and advise locals who oppose their government. They can also spread subversion and propaganda, while they aid native resistance fighters, to ultimately cause a hostile government to capitulate. Tactics focus on destroying military targets while avoiding damage to civilian infrastructure and blockading military resupply are used to decrease the morale of government forces.
In October 2019 at a workshop which included David Kilcullen and Ben Connable at RAND, Deputy Assistant Secretary of Defense Mick Mulroy publicly rolled out the Irregular Warfare Annex (IWA) to the National Defense Strategy of 2018. He explained that irregular warfare included counter-insurgency, counter-terrorism, unconventional warfare, foreign internal defense, sabotage and subversion, as well as stabilization and information operations. It had traditionally been perceived as a predominant counterterrorism (CT) effort used to fight violent extremist organizations, but that under the IWA the skills will be applied to all areas of military competition. These included competition against global powers competitors like China and Russia as well as rogue states like North Korea and Iran.  Mulroy said that the U.S. must be prepared to respond with "aggressive, dynamic, and unorthodox approaches to IW," to be competitive across these priorities. He also explained that under the IWA, both special operations and conventional forces would play a key role. 
The USA Department of Defense defines unconventional warfare as activities conducted to enable a resistance movement or insurgency to coerce, disrupt, or overthrow a government or occupying power by operating through or with an underground, auxiliary, and guerrilla force in a denied area. Also called UW.
- Asymmetric warfare
- Hybrid warfare
- Fourth generation warfare
- Irregular military
- Irregular warfare
- Low intensity conflict
- Partisan (military)
- Political warfare
- Psychological warfare
- Resistance movement
- Unrestricted Warfare
- A seminal work on unconventional stay-behind warfare is Major Hans von Dach's Der Totale Widerstand (Total Resistance).
- Six-legged Soldiers - A scientific warfare book on another potential form of unconventional warfare, by Jeffrey A. Lockwood
US & NATO specific:
- "Glossary". The Irregular Warrior. 2015-09-29. Retrieved 2017-09-07.
- "U.S. Army Special Forces Unconventional Warfare Training Manual November 2010". U.S. ARMY. March 3, 2011.
- "Unconventional Warfare Fundamentals". The Irregular Warrior. 2017-09-14. Retrieved 2017-09-17.
- "Department of Defense Dictionary of Military and Associated Terms" (PDF). pp. JP 1-02. Retrieved 25 June 2019.
- Insurgency Research Group – Multi-expert blog dedicated to the study of insurgency and the development of counter-insurgency policy.
- Allied war terminology (File #5a)
- [permanent dead link] Unconventional Warfare: Definitions from 1950 to the Present[dead link]
- Unconventional Warfare: A Better Path to Regime Change in the Twenty First Century
- Instruments of Statecraft: U.S. Guerrilla Warfare, Counterinsurgency, and Counterterrorism, 1940–1990
- Pentagon plans cyber-insect army