The term, conspiracy theory, usually refers to a theory that attributes the ultimate cause of an event or chain of events, or the concealment of such causes from public knowledge, to a secret and often deceptive plot by a cabal of powerful or influential people or organizations. The term is used pejoratively and usually involves a requirement for highly improbable causes.
In debunking a theory and pigeonholing it as a conspiracy theory, the strategy often employed is to prove the theory to be more improbable than the theory that is offered as conventional wisdom. For example, a theory that requires a number of conspirators to carry out a carefully orchestrated, complex set of maneuvers without a hitch may seem so difficult to carry out and the probability of keeping it all secret may seem so implausible that the theory can be ridiculed and dismissed as conspiracy theory out of hand with nothing more substantial than the assertion of violation of Occam’s razor and that one can keep a secret, but two cannot.
The official theory accepted and promoted by the U. S. government regarding the destruction of World Trade Center buildings 1, 2, and 7 requires that these buildings collapse into their footprints as the result of being struck by jet planes in the case of buildings 1 and 2 and by fire damage alone in the case of building 7. The story of the demise of buildings 1 and 2 involves untrained pilots who never learned to land a plane, much less conduct precise maneuvers in flight so as to strike the buildings in a precisely determined location at a specified speed with a known airplane weight. The video evidence shows that the second plane didn’t hit its target squarely in the center of the floor it struck, and the two planes hit the buildings at different altitudes—all consistent with novice piloting. And these unpredictable and different impact histories both resulted in essentially identical observed collapse sequences with both buildings falling as if by controlled demolition in free fall time and collapsing into the building footprint.
The alternate theory is that in spite of the airplane impacts, the buildings were rigged for demolition in advance, with knowledge that the plane attacks were scheduled, and the buildings were brought down after the impacts by controlled demolition. The attack on this theory by proponents of the official theory centers on the following points:
- Controlled demolition would require advance planning and rigging, weeks, perhaps a month.
- Controlled demolition would require the perpetrators of the demolitions to at least have knowledge of the plans and approximate schedule of the perpetrators of the jet plane attacks.
- Controlled demolition would probably require manual remote initiation of the demolition blast sequence.
- Controlled demolition plus jet plane attacks implies a much wider conspiracy than jet plane attacks alone.
- A false flag operation is a nonstarter, because it is unthinkable, and any theory that requires or even hints at this possibility will not be considered. 
Notice that none of these objections advances an assertion that the video evidence available to all is inconsistent with controlled demolition. As a matter of fact, those who defend the official theory make it a point not to examine the video evidence that might suggest controlled demolition in any detail. This is how NIST scientists and engineers explained their thought process:
“We assumed that A was the cause of X. We then found a way that A might have caused X. We were happy with this explanation. So we didn’t consider hypothesis B, which some other people had suggested.”
In this quotation A is the impact and the resulting fire (or just the fire in the case of WTC 7), X is the collapse of WTC 1 and 2 and WTC 7, and B is controlled demolition. I have studied the NIST report, and this is exactly their position.
So, let’s address the question, “Are the videos of the demise of the WTC towers and WTC 7 inconsistent with controlled demolition?” Two incontrovertible facts are (1) that each of the collapse sequences from the initiation of collapse to finish occurred in essentially the time required for a ball dropped off the top of the building to free fall to the ground, and (2) each building collapsed (essentially) into its footprint. These facts have been mentioned many times, and have failed to elicit any surprise from NIST researchers and supporters. The response is a dead-panned “No comment” or “So what?”
But these two incontrovertible facts are definitely consistent with controlled demolition. Every video of any successful controlled demolition shows the building collapsing according to a carefully planned choreography into its own footprint or into a predetermined debris field. If the building is planned to collapse into its own footprint the collapse time is very near free fall time. There are scientific reasons for the short collapse time. Longer collapse times result from some of the potential energy being employed to cause lateral force to be applied to direct the debris to a planned or accidental final resting place.
Then, if the observed collapses are consistent with controlled demolition, are they also consistent with the observed jet plane impacts and the resulting fires in the absence of controlled demolition? No, they are not. On June 15, 2009 a program titled “Blasted” was shown on the Science TV Channel. This program showed many controlled demolitions with interviews of the managers of the demolitions. The program made clear that each collapse is the result of a very carefully planned sequence of explosions involving precise timing and specific types and weights of charges for specific structural elements and architectural designs. Nothing is left to chance. The program also showed demolitions that went awry due to mistakes in demolition design. It is made clear that in no case would a collapse sequence caused by any sort of chance or imprecisely delivered damage produce the desired debris footprint or even a guaranteed total collapse. Free fall collapse time with minimum debris footprint requires that no falling part encounter resistance on its way to the ground. Nothing but a planned demolition sequence can produce this result.
We have now, without invoking any objection to any of the five points listed above, destroyed the official theory that the jet plane impacts and resulting fires caused the demise of WTC 1 and 2 and that fire alone caused the demise of WTC 7.
Q. E. D.
I suggest that it is time to put away the official U. S. government conspiracy theory and proceed from the observable facts of the case. There is much critically important work yet to be done before this case can be closed.
 Many 9/11 conspiracy theories have been presented to explain the September 11, 2001 attacks, many of them claiming that individuals in the United States government knew about the attacks beforehand and purposefully allowed them to occur, or orchestrated the attacks themselves, as a pretext for the "War on Terror", wars in Afghanistan and Iraq, increased militarization, expansion of the police state, and other intrusive foreign and domestic policies by which they would benefit. Proponents point to the Project for the New American Century, a conservative think tank that argues for increased American global leadership, whose former members include ex-Secretary of Defense Donald Rumsfeld, former Vice President Dick Cheney. Pearl Harbor" would be needed as a pretext for carrying out their plans for "United States global hegemony" in the 21st century. The 9/11 Truth Movement is the self-bestowed name of those who seek the purported "truth" about 9/11. (From http://en.wikipedia.org/wiki/List_of_conspiracy_theories#False_flag_operations ) and several other key Bush administration figures. A 2000 report from the group stated that "some catastrophic and catalyzing event — like a new
 David Ray Griffin, Debunking 9/11 Debunking, p.23.