Instead of running around like a collection of headless chickens and wasting time, energy, and brain-power concocting all this Baroque silliness, we should be agitating for a genuine investigation asking that question.

A genuine investigation asking only that question will not turn anything up at all if that isn't what happened. And the evidence suggests that it isn't what happened.

If you really want to get at the truth, you have to ask ALL relevant questions, including, "what caused the buildings to fall" and "what caused the damage to the pentagon". A real investigation that asks those questions can at least rule out the possibility that the administration was directly responsible if it wasn't, and that would be a good thing. And if your scenario is the correct one, then that will be discovered too, if they ask ALL of the relevant questions. But you won't get anywhere at all if you ask the wrong questions, or only the questions you particularly like yourself.