This is one of the reasons why I think that Islamic terrorists (which may or may not have been associated with Osama Bin Laden) is a more plausable theory than the hologrammatic planes remote controlled by pink lizards crap that I hear too much of (a similar comment I made on one of the many 9/11 "Truth" articles on Indymedia got hidden BTW):
Whether the towers fell down or not, it didn't matter. The fact that four planes were hijacked and went kamakaze into the WTC and Pentagon would have been justification enough for the Bush adminstration to go ahead with the "War on Terror". No need for any controlled demolitions at all, the plane crashes in themselves were horrifying enough, the fact that the steel girders were subesquently weakend as the result of the fuel laden jets crashing into them at top speed resulting in the collapse of the Twin Towers just added to the tragedy, but IMO even if they survived the planes ramming into them it the US would still have gone to war. As for WTC 7, I recall at the time that it collapsed about two hours or so after the other towers, and I don't recall any fatalities specifically from there, so what would the point be of demolishing an empty building?
As for who was behind the plane hijackings, it may never really be known who was behind it, or whether or not the US "intellgence" knew of it but "let it happen", but there seems to be this obsession that the US mainland could not be attacked, so therefore it must be an inside job, which is a pretty arrogant stance. I somehow don't think that even the US government would directly sanction the murder of 3000 of its own citizens, it may be naive thinking considering they are happy to murder tens of thousands elsewhere in the world, but there you go.
As an afterthought, I personally think that what happened on 9/11 is academic, it's what is happening now that is the main issue at hand, Al-Queda or no Al-Queda, what the US and it's coalition "partners" are doing in Iraq, Afghanistan, and possibly soon Iran as well is totally wrong, it is making the chance of a terrorist attack more likely rather than less.
Also think of this chain of events: US pisses off people in Middle East though its imperalist foreign policy -> Islamic terrorists conduct terror campaign -> War on Terror -> Terrorism threat increases rather than decrases due to reactions against US imperalism.
Now think of this: US does what it likes in the Middle East regardless of the suffering of the people -> US govt conducts 9/11 in order to justify grabbing the Iraqi and Iranian oil -> There were no terrorists to begin with, so we are immune to whatever goes on in the Middle East -> US can do whatever the fuck it pleases without anyone able to do anything about it (at home at least).