What was the war games going on at the same time as 9/11 attacks?

On the morning of September 11, 2001, the North American Aerospace Defense Command (NORAD) was conducting several training exercises or "war games". These included exercises such as Vigilant Guardian and Northern Vigilance which simulated hijackings and the scrambling of fighter jets in response. The coincidence of these exercises with the actual hijackings and attacks on that day has led some to question why the military was not better prepared to respond. However, the 9/11 Commission Report concluded that the war games did not have a significant impact on the military's response to the attacks, as the scope and nature of the events on 9/11 were far beyond what was being simulated in the exercises.