or being in these exercises could have helped...
Out of a range of scenarios being run on September 11, 2001, one was a "traditional" simulated hijacking. According to General Eberhart, after the first attack, "it took about 30 seconds" to make the adjustment to the real-world situation. Because of an increased number of staff, the exercise would prove to be an enabler of rapid military response for NORAD and its NEADS component, as senior officials who were manning NORAD command centers throughout the U.S. were available to make rapid decisions.
especially in NYC....
On September 12, 2001, there was due to take place the second part of an exercise known as Operation Tripod, set up to "test the plan to distribute antibiotics to the entire city population during a bioterrorism attack".
Richard Sheirer, director of the New York City mayor's Office of Emergency Management (OEM).
When the September 11, 2001, attacks began, Operation Tripod was immediately canceled as attentions turned to the real ongoing emergency. Because Pier 92 had been set up ready for the exercise, OEM staff were able to move there and quickly convert it into a large emergency operations center when their original command center (in WTC Building 7) was evacuated and later destroyed. Thus, within 31 hours of the attacks, OEM had a functional facility able to manage the search and rescue effort, just four miles north-northwest of the WTC site.[16] The exercise was later rescheduled and took place on May 22, 2002.[17]