For over 75 years, the United States has been at war. American cities have been destroyed, entire states overrun, American citizens forced to live under the heel of a foreign occupier, U.S. brigades and divisions destroyed wholesale by an implacable enemy. It would not be until the mid-1980’s that the tide began to turn against the foe…the dreaded Circle Trigon State.
The preceding is real. It happened, and continues to happen – and you, the Reader, likely never knew anything about it…Because, while it was real, it was only “sort of” real.
In 1946, in the aftermath of World War Two, a board of general officers – those who had commanded forces of all types, in all theaters around the globe, during the largest war in recorded history – was “convened” (although, in reality, most of the generals were surveyed by mail), and asked what they thought had been done right, and what had been done poorly, prior to the war…Resoundingly, on the “bad” side, the generals called for more realistic training.
Prior to the war (c.1940-1941), “training” – especially for the infantry – had consisted of lining troops up on opposite sides, handing one side blue armbands and the other red armbands, and having the units go at each other in a glorified game of “capture the flag,” as adjudicated by umpires who wandered the training ranges, making largely arbitrary calls on who had been “killed” or “wounded”, and which side had “won.” Both sides used doctrines and tactics straight out of the same training manuals of the service – mostly based on First World War tactics – with only a sprinkling of speculation about how things like tanks would be used on the battlefield. Little thought was put in on how potential opponents fought, nor what attitudes, tactics and doctrines they might have used, despite detailed battlefield reports from military observers working out of U.S. embassies around the world.
As a result, US forces – and their commanders – generally performed terribly in the opening stages of the war. In fact, it would not be a stretch to suggest that U.S. forces would have been better off without the extensive – and expensive – field training, beyond the most basic of “entry-level” tactical training.
One of the most important measures adopted to correct this abysmal training gap, at least by the US Army at first, was a breathtakingly radical idea, and idea that has metamorphosed and grown into a detailed regimen that now extends well beyond the military sphere:
The U.S. Army created a fictional enemy state: the “Aggressor Nation of the Circle Trigon Party.”
This was not like the thinly veiled names for potentially hostile nations that had been used for the famous color-coded war plans for the thirty-odd years preceding WW2. This was wholly different: the U.S. Army applied the same principles used by writers of popular fiction, to write what was essentially an “alternate history” of Europe at the end of WW2, a Europe that was partially reunited by a fictional Fascist political group. The scenario drew inspiration from the example of post-World War One Germany and the bodies of wandering troops known as the Freikorps, which had battled Communists across Germany in the chaotic aftermath of that war.

In this scenario, the United States, Great Britain and the Soviet Union failed to establish positive control over the battered remnants of Europe and abandoned most of their heavy weapons and equipment on the continent in a rush to repatriate their troops home, to get them back into civilian industries. (The details of why this happened were not explored; it was simply assumed, in order to create the setting.)
Into this tumultuous morass, surviving Fascist leaders in various countries reunited in Franco’s Spain, and created a multinational movement, called the “Circle Trigon Party” (PDF link) – modeled on the lines of various fascist parties from the 1930’s and 40’s – that quickly incorporated the bulk of the wandering and leaderless troops in this alternate Western European setting, and welded them into a new force. These forces promptly seized the heavy equipment and weapons left behind by the withdrawing Allies and began planning a preemptive assault on the United States, as the new state’s leaders saw the U.S. as was the most dangerous enemy they would face in the short term.
This scenario – never thought of before, on anything like this scale – was implemented by designating certain special training units to various Army posts around the country and using surplus equipment and uniforms, dyed black, to form units of the “Aggressor Army” to train units locally, on-base. The uniforms themselves, while distinctly different from U.S. uniforms, also included a slate of awards and decorations, while the rank insignias were entirely American in origin, but were either turned upside down, or pinned on in non-U.S. arrangements.

But neither were these units organized along regular U.S. Army lines. Instead, an “Aggressor Army Command” (YouTube link) was created in a building at Fort Riley, Kansas, that developed tactics and doctrines unique to this mythical force…tactics and doctrines that were not shared with the actual U.S. Army units who would face this curious opponent. The units were issued a variety of training tools, including inflatable tanks, trucks and artillery pieces; similar tools were used in Europe during the preparations for the D-Day invasion of Normandy. Additionally, standard psychological warfare techniques were used against U.S. troops by the Aggressor forces – leaflet drops by aircraft, Jeeps with loudspeakers to broadcast propaganda, and even radio broadcasts.
But it didn’t stop there.
At this “Aggressor Army” headquarters at Fort Riley, KS, extensive records were maintained of thousands of wholly fictional officers and troops, in a format similar to U.S. personnel summary cards. These personas were “assigned” to various training units, and troops were issued identification cards in these names and ranks; if “captured” during an exercise, these were the ID’s the “enemy” forces would hand over.
Even more remarkably, the Aggressor state, according to its back-story, had adopted the “constructed language” of Esperanto – and the troops were at least partly trained in its use. The reason for this was two-fold: captured troops would do their best to only answer questions in Esperanto, forcing intelligence units to attempt various forms of interpreting, and that all radio transmissions between Aggressor units were in Esperanto, forcing radio interception teams to also attempt to interpret the signals.
As the various exercises at posts were carried out during the late 1940’s and into the 1950’s, the Aggressor Headquarters in Fort Riley kept a careful score of when operations happened where and when, and what the outcome was…And, while U.S. forces didn’t always lose, they lost enough times, that the nation could frequently be presented as being in dire peril. One stark example demonstrated for American citizens was 1952’s Operation Longhorn (YouTube link), in which the town of Lampasas, TX and its civilian population were “captured” by Aggressor forces, and the citizens were given a very mild demonstration of what European civilians had faced under Nazi occupation ten years before.
The aim of the Aggressor force and the Circle Trigons was to train U.S. forces for large-scale combat against a foe who used very different tactics, and who saw the battlefield in a completely different light than U.S. commanders. Little thought was placed into “guerrilla warfare,” which has never really been given a stable place within the training cycles of United States troops. Oddities such as the “Pentomic Army” aside, the Aggressor Nation concept performed remarkably well…
But, the concept is not gone, by any means.
During the post-WW2 period, a polite fiction was maintained, in that the Circle Trigons were constructed as a Fascist, Nazi, German-like group…but everyone involved knew that they were actually training to fight the Soviet Union and its allies, exactly as anyone who knew of the color-coded war plans knew that “War Plan Red” (YouTube link) was code for war with England, or that “War Plan Orange” was about war with Imperial Japan.
Beginning in 1979, with the opening of the National Training Center (NTC) in the California desert, the U.S. military revamped its concept of the “aggressor” training tool, renaming it “OPFOR” (“OPposing FORce”), and creating multiple nations – versus a single state – with not simply a Soviet influence, but with Western and Third World influences as well.

The U.S. Army reactivated the 6th Battalion, 31st Infantry (“The Polar Bears“) from the 7th Infantry Division based at Fort Ord, California, and the 1st Battalion, 73rd Armor, redesignating the two units as the 177th Armored Brigade (Separate), to form the Center’s primary training unit. While maintaining their regular U.S. Army organization and training standards at one level, the 177th also “fought visiting” Army units by organizing and training itself to model a standard Soviet Motorized Rifle regiment (the fictional 32nd Guards Motorized Rifle Regiment, known jokingly as “the best armored regiment in the Soviet Army”). After the 9/11 Attacks, the brigade transitioned to training for counterinsurgency warfare training (along with a similar unit at Fort Polk, Louisiana) for units headed to Iraq and Afghanistan…And now, following Vladimir Putin’s Russia reminding the world that large-scale warfare is not, in fact, a thing of the past, the Center has switched back to training for major-scale warfare against a “near-peer” opponent.

This model has worked so well as a training tool, both the U.S. Marine Corps (PDF link) and U.S. Air Force created similar training units of their own. So far, the U.S. Navy seems to be the only holdout.

For the casual reader, much of the background information and training materials are available online for free, courtesy of the U.S. Army, via its ODIN website, part of the Training & Doctrine Command (TRADOC), where you can explore the challenges of fictional nations like Atropia, or Olvana. (For an alternate wargame setting, based in a fictional Latin American country – once used by Great Britain as a wargame exercise – see the MapSymbs website.)
While notionally interesting, the foregoing history of recent developments in military training is something that people need to know. The gaming environment is not all about cartoon ‘first-person shooters’, played by bored kids in their parents’ basements. Wargaming simulations have been, and continue to be, one of the most valuable pieces in the training toolbox.
And this Marine doffs his cover to the Army, for getting that right.



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