Could Military Jets Have Stopped the 9-11 Attacks?

"[Sic] at 8:55 a.m., American Airlines Flight 77, aloft from Washington, broke from its flight path. The hijackers turned off the plane's transponder, and it stopped sending data to air traffic controllers. The FAA lost radar contact with the plane.
It is at this point that relatives of the family members say the FAA and NORAD could have responded differently. They had 45 minutes until the plane would hit the Pentagon.
By then, American skies were in chaos. At one point, the FAA was tracking 11 planes that it feared could have been hijacked, said Laura Brown, a spokeswoman for the agency. Air Force fighters were taking off from bases unarmed, and someone floated the idea of using one of them to ram a hijacked airliner.
Still, two events would have been required for the Pentagon strike to have been averted.
First, President Bush would have had to have ordered that any hijacked airliners be shot down; the military's rules of engagement did not allow for that without such presidential intercession. Bush ultimately did make that call, but only after the Pentagon was hit.
Second, NORAD's F-16 Fighting Falcons at Langley Air Force Base, near Norfolk, Va., would have had to have been launched sooner.
Why they weren't is unclear.
According to NORAD's timeline, those fighters received the scramble order at 9:24 a.m., 30 minutes after Flight 77 made an unauthorized turn. That suggests the FAA took an inexplicably long time to alert NORAD. But Jane Garvey, former head of the Federal Aviation Administration, said it had informed NORAD earlier in a telephone call.
Retired Maj. Gen. Larry K. Arnold, who was in charge of domestic air defenses on the day of the attacks, said it was "physically possible" that fighter jets could have beaten the civilian airliner to the Pentagon had they been activated earlier.
Another decision not made: NORAD did not launch all available fighters even when it became apparent that multiple suicide hijackings had taken place.
"It's inexplicable why they did not get air protection up in time to thwart that crash," Breitweiser said. She also asked why the F-15s sent to New York were not sent after Flight 77.
The three nearest fighters - an extra armed plane happened to have been ready at Langley - took off at 9:30 a.m. At 9:40 a.m., when Flight 77 hit the Pentagon, they were still 100 miles away.
Had they made it, the pilots and their commanders would have to live with the consequences of shooting down a plane filled with mostly innocent people. Some military officials have suggested they probably would be second-guessed for not allowing the passengers more time to try to take the plane back.
In addition, shooting down an airliner over a populated area has the chance of creating even more destruction. The fighter's missiles most likely would have created large pieces of wreckage, or created a single flaming, out-of-control missile careening into the city. The 124 lives lost at the Pentagon would have been spared, but what if the wreckage had hit a nearby apartment tower?"