That "Loose Change" video is somewhat silly. They try to point out all the terroism-related things about the WTC in the time before 9/11 as if to try and show that someone knew that 9/11 was going to happen. For example, the part about the insurance coverage being purchased for the WTC that covered terrorism. People forget that Islamic terrorists tried (unsuccessfully) to bomb the WTC in 1993.
Speaking of bombing the WTC, let's suppose the gov't did really want to destroy the WTC. Much of that video focues on the theory that the building was brought down by a controlled demolition. Forgetting the numerous physical flaws with that argument (and the lack of a plausible motive), let's run with it for a moment.
If the building was ultimately brought down by a controlled series of demolitions rather than a 100 ton plane slamming into the building at +400 mph, why concoct an elaborate scheme with planes flying into it? Why not just use miltary explosive specialists to put shaped charges on the building and blow it up that way and then blame it on terrorists?
I once saw an episode of Scooby Doo in which Shaggy and Scooby were trapped in a jail. The key to the cell was a few feet away hanging on a peg. The guard, of course, was asleep. Shaggy managed to squeeze himself through the bars and carefully and quietly slinked across the room and grabbed the key. He then squeezed back into the cell, reached through the bars, and unlocked the door. The joke of it is that he could have just unlocked the door from the outside; why sneak back into the cell only to reach around and unlock it?
The theory that the WTC was brought down by a controlled demolition is a bit like that Scooby Doo episode. If you are just going to blow the building up anyway, why go through all the trouble--an extremely elborate scheme--of creating the impression that it was destroyed by terrorists flying planes? Why not just blow the building up yourself and blame it on 19 guys from Saudi Arabia? That way you can cut-out all that plane bullshit in the middle and have the exact same result. By the way, the bombing theory wouldn't be such a tall-tale, given that terrorists tried the very same thing in 1993.
Unfortunately, 9/11 was so unprecedented in its nature that many people are simply in disbelief about how it happened. Because the things that took place on 9/11 really push the envelope of what we were willing to accept as possible before that day it is ripe for skepticism and disbelief.