You're buying into a whack-job conspiracy theory, which makes me tend to believe that you're a whack job, too. If I come across as harsh, well, I never have been know to suffer fools gladly.

Once again, here's some basic aerodynamics for you: That top speed for an F-15 is for one that has no external stores such as fuel tanks or weapons. It would've been rather pointless to send it out without missiles, so the top speed is considerably less than Mach 2.5 in combat configuration.

The transponder is used to send coded identification information (4 octal digits plus altitude data when operating in Mode C) so the computers connected to the ATC radar can keep track of the plane. This causes identification information to be displayed on the controller's radar screen. Transponders with encoding altimeters are also interogated by TCAS systems on board many planes to aid in collision avoidance. In no way is a transponder used to navigation.

A plane going NORDO isn't necessarily a signal of hostile intentions. For example, consider what happened to the Learjet that Payne Stewart was riding in a few years ago. From all indications, the pressurization system failed and the crew didn't get their masks on in time. The plane continued to fly on autopilot with an unconscious crew until it ran out of fuel. The plane went NORDO because the crew wasn't able to respond to radio calls but the transponder kept functioning. It went well off course by hundreds of miles, and fighters were dispatched to see if they could determine what was wrong. All they could do was fly formation with the plane and confirm that the cockpit was iced over (an indication of pressurization loss). They might've been ordered to shoot down the plane if it looked like it was coming down in a populated area but that didn't prove necessary.

Planes go NORDO on a fairly regular basis. It can happen when the plane has electrical problems, problems with the avionics, or problems with the crew. Perhaps the most common cause is getting the wrong frequencies dialed in when in conjested airspace (e.g. NYC) and rapid frequency changes are ordered. That happens even to professional airline crews. The audio quality on aircraft radios sucks, so it isn't hard to misunderstand a frequency number or to get some digits transposed.

Never before had the FAA had to consider shooting down a hijacked plane or one that went NORDO. Never before had they had to contend with 4 airliners hijacked within minutes of one another. Never before had an airliner been used as a cruise missile. Never before had they been ordered to clear the skies of all aircraft. This was an unprecedented situation and everyone involved reacted as best they could under the circumstances.

I read an article last week that one of the Air Force commanders actually discussed ordering fighters to ram the airliners if it came to that. At the time, no one knew how many planes might've been hijacked (there were over 4000 planes in the air at the moment) and there just weren't many armed interceptors on alert. That's how desperate the situation was at the time. For whack jobs like you to accuse the military (and the Bush Administration) of deliberately allowing the attacks to take place is a deep insult to everyone involved. You should be completely ashamed of yourself.