Norad had run drills for several years of planes being used as weapons against the World Trade Center and other U.S. high-profile buildings, and "numerous types of civilian and military aircraft were used as mock hijacked aircraft". In other words, drills using REAL AIRCRAFT simulating terrorist attacks crashing jets into buildings, including the twin towers, were run. See also official military website showing 2000 military drill, using miniatures, involving a plane crashing into the Pentagon.
Indeed, a former Los Angeles police department investigator, whose newsletter is read by 45 members of congress, both the house and senate intelligence committees, and professors at more than 40 universities around the world, claims that he obtained an on-the-record confirmation from NORAD that ON 9/11, NORAD and the Joint Chiefs of Staff were conducting a joint, live-fly, hijack exercise which involved government-operated aircraft POSING AS HIJACKED AIRLINERS.
On September 11th, the government also happened to be running a simulation of a plane crashing into a building.
Moreover, there are indications that some of the major war games previously scheduled for October 2001 were MOVED UP to September 11th by persons unknown.
Interestingly, Vice President Cheney was apparently in charge of ALL of the war games and coordinated the government's "response" to the attacks. See this Department of State announcement; this CNN article; and this previously-cited essay.
Moreover, a former air traffic controller, who knows the flight corridor for the two planes which hit the Twin Towers "like the back of my hand" and who has handled two actual hijackings, says that planes can be tracked on radar even when their transponders are turned off, and further says that the Pentagon tracked three of the four flights continuously from the time they were hijacked to the time they hit their targets (part of statement is contained in this interview).
Additionally, this diagram shows that the hijacked planes flew over numerous military bases on 9/11 before crashing. See also this essay about the war games; this essay regarding the stand down of the military; and see this war game proposal created before 9/11 revolving around Bin Laden and including "live-fly exercises" involving real planes, later confirmed by this official Department of Defense website.
Which scenario is more likely from a strictly logistical perspective:
(1) An outsider sitting in a cave defeating the air defense system of the sole military superpower; or
(2) Someone like Cheney -- who on 9/11 apparently had full control over all defense, war game and counter-terrorism powers -- rigging and gaming the system?
Fighter jets were also sent far off-course over the Atlantic Ocean in the middle of the attacks (testimony of Senator Mark Dayton), so as to neutralize their ability to intercept the hijacked airliners. Could Osama Bin Laden and his sent-from-the-cave band of followers have exercised this degree of control over the military? Obviously not.
And air traffic controllers claim they were still tracking what they thought were hijacked planes long after all 4 of the real planes had crashed. This implies that false radar blips remained on their screens after all 4 planes went down, long after the military claims they purged the phantom war-game-related radar signals. Could Bin Laden have interfered with the full purging of false radar blips inserted as part of the war games? In other words, could Bin Laden have overridden the purging process so that some false blips remained and confused air traffic controllers? The answer is clear.
Therefore, it is statistically much more likely that Cheney and/or other high-level U.S. government and military officials pulled the 9/11 trigger than that Bin Laden did it. At the very least, they took affirmative steps to guarantee that the hijackers' attacks succeeded.