“I’ve never seen so much real-world stuff happen during an exercise.”
– Major James Fox, Northeast Air Defense Sector, September 11, 2001
Key military personnel who were responsible for protecting the U.S. against the 9/11 attacks may have been seriously hindered in their ability to respond because of a large-scale air defense exercise they were participating in when the attacks occurred. Evidence indicates that the personnel, whose responsibilities included ordering fighter jets into the air to intercept the hijacked planes, were unclear about what was “real-world” and what was “exercise.” They may have been led to believe that the terrorist attacks were just simulated scenarios.
These individuals worked at the Northeast Air Defense Sector (NEADS) in Rome, New York. Audio recordings of the operations floor at NEADS reveal staffers suggesting that the catastrophic events of September 11, 2001 could have been part of the exercise. They sometimes even made jokes and laughed about what was taking place, further indicating that they were mistaking actual events for exercise simulations. Even senior commanding officers have admitted wondering if the terrorist attacks were part of the exercise.
And while staffers sometimes apparently made clear that an event was unconnected to the exercise by referring to it as being “real-world,” there is evidence that the term “real-world” may in fact be a way to describe live events played out within an exercise, perhaps involving real aircraft getting airborne, rather than just hypothetical scenarios.
Furthermore, NEADS personnel previously participated in exercises that included scenarios resembling the 9/11 attacks, such as plane hijackings and aircraft being crashed into skyscrapers in New York, and this could have increased the likelihood that they would mistake the events of September 11 for exercise simulations.
Although much remains speculative, the available evidence raises serious questions about whether the exercise at NEADS on September 11 was a deliberate tactic used to hinder skilled and dedicated professionals, thereby preventing them from stopping the terrorist attacks.
NORAD’S ‘SIMULATED AIR WAR’ ON SEPTEMBER 11
A key agency responsible for protecting the U.S. from an airborne attack, like what happened on September 11, is NORAD, the North American Aerospace Defense Command. NORAD is the military organization responsible for monitoring and defending the airspace over the United States and Canada. Within the U.S., it is divided into three sectors. The 9/11 attacks took place in the airspace monitored by its Northeast Air Defense Sector, NEADS. It was therefore personnel at NEADS who were responsible for trying to coordinate the U.S. military’s response to the hijackings. These individuals, however, were in the middle of a major training exercise when the attacks began.
“Vigilant Guardian” was an annual exercise conducted by NORAD that was several days underway on September 11. All of NORAD took part in it.  Vigilant Guardian has been described as a “simulated air war” and as “an air defense exercise simulating an attack on the United States.”  Remarkably, it was scheduled to include a simulated hijacking at around 9:40 a.m. on September 11. The exercise “was designed to run a range of scenarios” that day, according to Vanity Fair, “including a ‘traditional’ simulated hijack in which politically motivated perpetrators commandeer an aircraft, land on a Cuba-like island, and seek asylum.” 
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