One of the squadron's fighter jets wears a hammer and sickle on its intake cover. The American jet has landed after trying to attack Australia.
They're the kind of contradictions you work with when you fly for the US Air Force as a full-time adversary to its own units, and allies.
"The beauty of the 18th Aggressor squadron is we can replicate and fly any role," Captain Chis Prochnow said.
"When somebody, a customer, another country, another unit comes to us we can provide anything ... any type of mission you would expect from an adversarial nation."
The American pilots flew in from Guam and Alaska last week to play "red air" in the Williamtown phase of Australia's biannual air warfare instructor course.
They are testing the RAAF's most elite pilots and officers in defensive missions currently being held off the coast of Newcastle.
"Essentially, we have aircraft providing an escort role and aircraft providing a strike role and then we put those together to create that offensive counter air to try and destroy some sort of notional target, which they [the Australian students] are trying to defend," Mr Prochnow said.
Commanding officer of Williamtown's 88 Squadron, Wing Commander Tim Main, said the six-month course, held between Canberra, Pearce, Williamtown and Darwin, was the "highest training" the students would complete during their careers.
"We select them on course because they are the best at what they do and the course hones the skills they've got, challenges them, and expands their experience and leadership attributes," he said.
The difficulty of the missions, which can range from 30 minutes to six hours in length, will increase over the next week-and-a-half.
"The operating airspace is on the coast. We've got a really large bit of sky there to play with," Mr Main said.
"It's like a football game, and having no umpire, but both sides know the rules and they adjudicate as they go through the practice game.
"They communicate on the radio between red and blue to assess whether someone has taken a kill, so to speak, during that flight. When they land the data is reviewed."
Mr Main said naval weapons were also being worked into the exercises, including HMAS Melbourne.
"We've got the P-8 arriving later today. The P-8 is a maritime aircraft so that really suits the environment here, operating off the coast."
The Americans said they were dealing with their own "unique challenge" - Australian slang.
"We all speak English but it seems sometimes we don't. We're just getting over ... just different words for different things," Mr Prochnow said.