U.S. OPFOR soldiers playing the role of Iraqi insurgents in Fort Polk, Louisiana.^{[note 1]}

An opposing force (alternatively enemy force, abbreviated OPFOR or OpFor) is a military unit tasked with representing an enemy, usually for training purposes in war game scenarios. The related concept of aggressor squadron is used by some air forces. The United States maintains the Fort Irwin National Training Center with the 11th Armored Cavalry Regiment serving in the OPFOR role. Fort Johnson's (formerly Fort Polk) Joint Readiness Training Center (JRTC) is another major training site typically reserved for light infantry units, and the OPFOR are the 1st of the 509th Airborne Infantry Regiment. The Army's Joint Maneuver Readiness Center (JMRC, at Hohenfels, Bavaria, Germany) has the 1st of the 4th Infantry Regiment as their OPFOR. Other major units include the First United States Army which consists of 16 training brigades that often also serve as OPFOR.

At a basic level, a unit might serve as an opposing force for a single scenario, differing from its 'opponents' only in the objectives it is given. However, major armies commonly maintain specialized groups trained to accurately replicate real-life enemies, to provide a more realistic experience for their training opponents. (To avoid the diplomatic ramifications of naming a real nation as a likely enemy, training scenarios often use fictionalized versions with different names but similar military characteristics to the expected real-world foes.)

Units

United States

A UH-1H replicating a Mi-24 at Fort Irwin in 1985

There are three major training centers that utilize home-based OPFOR units for the US Army:

• The National Training Center or NTC at Fort Irwin, California—home unit is the 11th Armored Cavalry Regiment (the Blackhorse)^[4]
• The Joint Readiness Training Center or JRTC at Fort Johnson, Louisiana—home unit is the 1st Battalion, 509th Parachute Infantry Regiment (the Geronimos)^[5]
• The Joint Multinational Readiness Center or JMRC (formerly known as the Combat Maneuver Training Center or CMTC) at Hohenfels, Germany^[6]—home unit is the 1st Battalion, 4th Infantry Regiment (Separate) (the Warriors)

Various US military installations or major units have their own local versions of opposing force used for training exercises. The joint Australian–US military exercise "Crocodile '03" featured an Australian-led opposing force in which soldiers from a range of Australian units worked together with a US Marine Corps contingent.^[7]

Several state defense forces have served as OPFOR units when training with the National Guard. The California State Guard,^[8] the Georgia State Defense Force,^[9] and the New York Guard^[10] have provided OPFOR services to their respective National Guard counterparts. In 2018, the Georgia State Defense Force established the OPFOR Battalion^[11] to assist National Guard Soldiers with pre-deployment training.

Ranks

Officer ranks

Rank group	General / flag officers										Senior officers						Junior officers								Officer cadet
Aggressor Army (1953–1962)[12]
	Marshal		General of army		General of corps		General of division		General of brigade		Colonel		Commandant		Major		Captain		Lieutenant		Sub-lieutenant		Warrant officer
Aggressor Army (1962–?)[13]
	Marshal		General of army		General of corps		General of division		General of brigade		Colonel		Commandant		Major		Captain		Lieutenant		Sub-lieutenant		Warrant officer
Rank group	General / flag officers										Senior officers						Junior officers								Officer cadet
Aggressor Air Force (1953–1962)[14]
	Air marshal		General of air		General of air army		General of air corps		General of air division		Colonel		Commandant		Major		Captain		Lieutenant		Sub-lieutenant		Warrant officer
Aggressor Air Force (1962–?)[15]
	Air marshal		General of air		General of air army		General of air corps		General of air division		Colonel		Commandant		Major		Captain		Lieutenant		Sub-lieutenant		Warrant officer

Other ranks

Rank group	Senior NCOs																						Junior NCOs						Enlisted
Aggressor Army (1953–1962)[16]																													No insignia
	Sergeant major						Staff sergeant		Senior sergeant		Platoon sergeant						Section sergeant						Corporal				Senior private		Private
Aggressor Army (1962–?)[17]																													No insignia
	Sergeant major						Staff sergeant		Senior sergeant		Platoon sergeant						Section sergeant						Corporal				Senior private		Private
Rank group	Senior NCOs																						Junior NCOs						Enlisted
Aggressor Air Force (1953–1962)[18]																													No insignia
	Sergeant major						Staff sergeant		Senior sergeant		Platoon sergeant						Section sergeant						Corporal				Senior airman		Airman
Aggressor Air Force (1962–?)[19]																													No insignia
	Sergeant major						Staff sergeant		Senior sergeant		Platoon sergeant						Section sergeant						Corporal				Senior airman		Airman

Gallery

• 
  49th Royal Tank Regiment Matilda II with swastika and Iron Cross markings to denote opposing force status during an 1941 exercise in Dover.
• 
  New Zealand Defence Force soldier denoting opposing force status by wearing Desert Disruptive Pattern Material (DPM) in a temperate environment.
• 
  Scene from a simulated Royal Marines beach landing during the 2009 Bournemouth Air Festival; "opposing force" Marine is bareheaded and wears Desert DPM, "blue force" Marines in the background wear berets, camouflage face paint, and woodland DPM. An additional distinction is achieved by the use of iron sights on the "opposing force" Marine's L85A2, while those of the "blue force" are fitted with the then-standard SUSAT sight.
• 
  A sniper from the French CENZUB opposing force wearing a blue-and-gray version of Camouflage Central-Europe.
• 
  51st Fighter Wing airman denoting opposing force status by wearing his Battle Dress Uniform back to front (note the contrast of the uniform with the Individual Integrated Fighting System vest that is also being worn).
• 
  4th Infantry Regiment soldiers wearing United States Army opposing force uniform (Battle Dress Uniform in black with olive 'OPFOR' shoulder title)
• 
  An OSV replicating a Soviet BMP at NTC, Fort Irwin, CA
• 
  US Marines using a former Soviet MT-LB vehicle as part of the OPFOR during an exercise
• 
  Michigan National Guard OPFOR wearing tiger stripe camouflage uniform and carrying a simulated RPG-7.
• 
  OPFOR rank insignia mimicking the Soviet style (used during the Cold War)

Notes

References

Further reading

Wikimedia Commons has media related to Opposing forces.

• Validating the "Enemy" (discusses the United States Army OPFOR units and post-Cold War changes to OPFOR.)
• The Circle Trigonists (Aggressors), a summary of the opposing force Aggressor used by the United States Army from ca. 1946–1978