Conspiracy theories aren't unlike professional wrestling: It's full of BS but surely entertaining.
You don't need to say you're not an engineer - that's obvious - LOL

It's just like I don't need to say that I'm an asshole, right?
Seriously though, there are lots of intelligent people in this thread. But why all of the shallow speculation?
Even Bin Laden was surprised by the collapse. He didn't expect that to happen.
The towers were designed to sustain a horizontal impact of a Boeing 707-320, but no consideration was given to the widespread and sustained 1500+ degree environment created by the enormous amount of fuel.
How did the all of the columns get compromised? Immense heat and subsequently a behavior called Viscoplasticity. This leads to a creep buckling of the columns, which consequently lose their load capacity. Once the critical floor collapsed, there was so much compound kinetic energy and incremental downward velocity from the upper part of the building that the runaway breakdown would not stop until it hit something stronger: the ground.
Why didn't the tops of the towers tumble? It's called a Truss system. Several were redundantly implemented above the critical floor along both their long and short axes. Professionals think about this shit in advance.
As far as the Jew theory goes - that's nuts. Please consider the source. Muslim publications are typically loaded with antisemitic propaganda. Even my Muslim buddies repeat it like robots. But if you corner one in an argument, he (because women won't talk) will act like any fundmentlist whacko: folds like a cheap suit and acts like a broken record; usually by quoting scripture and spewing nonsensical gibberish. The number of Jews working in the towers was barely over 1 percent. Hardly a quantifiable crossection, don't you think? Now if all of the WTC Jews took a sick day, wore a firesuit/parachute or all went out for Starbucks at the same time on 9/11/2001, then you got something. Besides, this happened in the morning, so how could work attendance be legitimately and collectively tallied? It's hearsay and therefore, bullshit.
Al Qaeda's strategy for this operation was simple: Low tech, high concept. They were literally flying by the seat of their pants. For years those fuckers couldn't get a camcorder to work and still fucked it up with Daniel Pearl. (Taliban,Al Qaeda, et al)
Do we believe the Apollo moon landings were faked? Tell Buzz Aldrin that to his face and he will kick your ass - medicare or not. (He punched one douchebag in the mouth not long ago for that) Back then, Astronauts had to be crazy - they were flying by the seat of their pants, too.
I can think of another person flying by the seat of his pants - and that's a little white guy pretending to be a woman and using an interracial site as a political soap box...
*SNAP*
LOL