Carol, I think you are displaying a similar error in thinking to that of folks who insist that Creationism is a valid theory. One of the questions they think they can frame is "What is the probability of life, the universe, and everything?" and they come up with made up probabilities and they conclude that the reality we know is well nigh imossible by 'laws of nature' and therefor, a Creator was required.
But the probability of "Life, The Universe, and Everything" is well known. It is 100%.
Likewise, we've got planes flying into buildings, the buildings on fire, and the buildings collapsing. It happened within a very short period of time, it is documented on all sorts of media, and the folks who claim that an airplane didn't hit the Pentagon, other little apparent inconsistencies like that, have been disproved.
The fact that structural engineers may still be arguing over the details of what collapse led to what further collapse does not change the facts of the collapse itself.
Now, as far as the more scientific 'appearing' articles that are coming out claiming metallurgical evidence of thermite, I'm not that kind of engineer. I can't tell if there is any sense to it, but I also can't tell if those photos are what they are supposed to be, the 'scientists' who they are supposed to be, that folks aren't doing their best attempt at falsification and lying. I think that is the sort of thing we may be seeing, because folks have staked reputations on some very wild theories, and they might very likely be lying like hell.
Therefore, it is coming time that we start to do a bit of epistemology on these articles. So and so wrote this and is actually in a position to know this.
I believe the planes and passengers were real, the terrorists and their backgrounds were real, and the buildings really fell because of them. The 'truther' movement has been marked not by a coherent strain of logical consistency, but by a multiplicity of claims woven out of any little fragment of unknown elements that can be exploited. It is sort of like saying anything that is not only plausible, but remotelty believable by anyone with any axe to grind, the theme being: "you can't trust anyone but me".