I'm actually not going to even remotely claim to guess as to "who" did anything, however I do believe that the information that we have been given is absolutely not correct in terms of the physics aspects of the collapses of WTC Towers 1,2 and 7...especially 7.
Though it will avail nothing, I served 6 years in the military, have 2 sons in the Navy and regardless of how patriotic I am, I am absolutely allowed the right to examine any evidence and make up my own mind as to whether I am being told the truth or not. It is my opinion that "that" right to do so is not only a right, it is a duty as given us as part of our citizenship.
My gut instinct on watching the original "day of the event" footage was one of "you have to be kidding me/no way that happened". I think that my gut reaction was based upon being a history channel/national geographic addict and simply devouring hours upon hours of "how it was made" type documentaries.
I am not a licensed engineer, but I do know enough about physics and engineering to know that the stories we have been told in terms of the "official explanation" are hogwash. That does not mean I know anything more about what really happened, but when I cannot trust the sanctioned story, then it is natural that my suspicions be raised to some degree.
I am aware that to even question anything, to be a voice that expresses even a moments hesitation in accepting the spoon fed version of the facts of an event is in todays atmosphere is less than patriotic to the point of being considered traitorous. That my friends is what concerns me the most. Questioning should never be considered evil. If you do consider it that, then you in essence handily discard one of the freedoms that distinguishes this country from most others.
I am not an expert on much of anything, but it is articles written by engineering professors and the like that I think that an open minded person should examine, if nothing more than to do the due diligence that we all have the duty to do.
I was originally going to post links to the various physics and engineering papers written on this topic, but to be honest, the resulting arguments of the various points of the papers would be more effort than it's worth. I really have no interest in convincing anyone of anything, I simply have an interest in maybe performing a tiny nudge in the interests of not being blind in the name of patriotism. There have been too many postings on this board that slam those that do not come to the exact same conclusions as others. Give them a moment of credit towards their intelligence. Just because I saw a show that said that Kurt Cobain influenced the radical arm of islam and my pug puppy to pilot planes into the towers and the resulting puppy bark shattered the 47 core support columns into 30 ft lengths does not mean that I believe it...that is the beauty of our country, the ability to examine ALL evidence and come to our own conclusions, regardless of whether those conclusions match the official story. Those that would quiet the right of someone to express their thoughts are more guilty of being unpatriotic in my opinion than those who would express the worst possible opinions as to what happened and who was involved.
In the end, if one comes to the exact same conclusions after examination of other explanations then good..that means that your gut feelings coincided with physics and known facts. However, physics don't often lie.
Regardless of how/what happened, it is a tragedy when any event of this magnitude occurs and god bless those that perished in this tragedy.