Because:

There were no Airliners involved in the 9/11 hits.

I am now completely four-square behind the no-planes explanation, having viewed the Webfairy - who has discarded the holograms - and 911hoax.com sites for the umpteenth time. This is indeed Occam's Razor at its sharpest. No longer do we need the infamous stand-down, FAA incompetence, NORAD complicity and incomprehensible flight-paths (although we still need the war-games for maximum confusion and for the pseudo-hijackings). Thus is a massive amount of deadwood and personnel eliminated from the caper. In fact, the no-planes explanation is the ONLY rational, completely logical explanation there is. Once you have eliminated the impossible, whatever remains, however improbable, is the truth. Well, near-as-dammit, anyway.

Consider the LIVE footage where we see the SAME CNN (or CBS) feed - on ALL channels (don't forget these Bozos have already got together on "how to cover the next terrorist attack", and no doubt did so before 9/11). All we see for about TWO seconds is a silhouette resembling an airliner, travelling from west to east into the blazing sun, before it conveniently disappears behind the North Tower. The entire South Tower IS NOT SEEN. (This live feed could easily have been delayed for x seconds before transmission - enough time for the techno-spooks to insert the artifact, when they knew the rough location of the fireball. The artifact can, of course, be inserted in real time, anyway). This is BY FAR the VERY BEST angle - side on to the artifact at optimum distance and a totally hidden South Tower - to deceive us. (And all set up in a choatic New York in less than 17 minutes! Miracles will never cease). But it comes at a price: the artifact in later doctored VIDEO transmissions has to execute a near-impossible (some pilots say impossible) banking maneuver for such a giant airliner, so that the angles, the artifact's "flight path", the explosion and the damage to the building, correlate. After this "live" footage, OBVIOUSLY, ALL SUBSEQUENT TRANSMISSIONS ARE FROM VIDEO, some from different angles, which were, and are, continually being refined with each transmission (eg. the widening of the artifact's arc of approach and angle of attack from 2-3 o'clock to 1-2 o'clock as viewed from the north). All this can easily be done. When was a different "angle of attack" televised after that brief "live" hit? Not for many hours later. MINUTES are enough to accomplish the doctoring of all videos, from all angles.

All the "amateur" (my ass) videos have been thoroughly - and brilliantly - debunked by the Webfairy and Scott Loughrey; they surely deserve a Medal Of Honor.

Eyewitnesses. As any psychologist will tell you, their testimony must always be taken with a dollop of salt, especially when - in shock and well after the event they are recalling - the meme of planes-planes-planes has been thoroughly implanted. And where were the 200+ Israeli spooks and FEMA that morning? I would bet my bottom dollar they were playing their roles as eyewitnesses (and false-evidence planters) at the WTC - just like the ubiquitous, impossibly-located "Naudet brothers" - and at the Pentagon. Assume the missile (or no missile at all, just explosives in the building itself) comes in from the south. Most people are looking, if they are looking at all, directly at the gaping hole and smoke on the NORTH side of the North Tower. So, like us watching the live transmission, they cannot possibly see it. Witnesses at ground level have hardly any chance of seeing it, even from the south, east, or west, what with all the obscured views; and they have no sound (certainly not the deafening roar a giant airliner, 250 meters away, flying at 450mph, would make in the thick air of Manhattan) to aid their locator faculties - this is a near-silent, very fast moving air-to-surface missile we're talking about.