I shouldn't even weigh in on this one, because the conversation seems to have turned to a civil tone, but I don't believe the WTC was collapsed using explosives. We analyzed it in my engineering class and came to the following interesting conclusions.
For starters, the WTC was a totally different structure compared to other steel buildings. All the supports are at the edges. For anyone who's ever been there the windows were really skinny because of the steel beams that ran vertically and pretty close together. I watched an interview with the original builder who described the building as a mesh that was hollow in the middle. This was to allow more floor-space without so many vertical supporting beams like a typical steel skyscraper.
Now, it is true that the building was designed to withstand an "accidental" hit from a plane. but the largest plane at the time was I think 1/2 or 1/3 the size of the planes that actually struck the WTC and carried less fuel. The building was simply outclassed by the size of the new planes.
I too have seen the pieces at NIST (I live like 20 minutes away) and the majority of them failed due to over-stress and not heat. Here's what happened. The building is almost entirely supported by the outside edges (think how string a beer can is in compression top-to-bottom but if you squeeze the sides it crumples easily). The second plane almost missing was actually a boon to the terrorists. The near miss caused it to hit on more of a corner, this is similar to kicking the legs out from under a table. This loss of a support, combined with moderate weakening of the steel from the fuel fires, caused the upper floors to collapse onto lower ones. This collapse over-stressed the rest of the structure. It collapsed downwards because that's the direction of the falling upper floors which ltierally drove the bottom half of each tower into the ground.
The windows blew out because of trapped air. Furthermore, given the steel-mesh structure of the building you can't implode it like a controlled demolition. Those controlled demolitions take the foundation out of a building. The foundation for the towers is several stories underground. If they had actually detonate the foundation you wouldn't have even heard it.
The remaing tower fell because it shares a foundation with the bigger ones. There was a freaking subway station under the towers. A huge underground shopping mall. When the larger two towers collapsed it severely destabilized the whole block. It was really like one large building with a bunch of towers shooting up from it.
To put it plainly and simply, the terrorists hitting the WTC towers with two planes cause the collapse. If it had been just the first plane they might have stood, if the second had hit a side and not a corner it might have been different, etc. But it was the planes that caused the collapse.
*deep breath*
Now, that being said I do strongly oppose the NAU, NAFTA, etc, etc. I think that the media and money controls too much of the freedoms in this country. I do not believe GW Bush orchestrated 9/11, but I do believe he used it opportunistically to pass a lot of scary laws. I am a registered Republican, but I am not a supporter of GW.
Here's a semi-rhetorical question. How can so many liberals claim that GW is the devil on earth, orchestrating countless conspiracies to control everything, and then in the same breath call him too stupid to know what's going on? Pick a side. I think he used 9/11 to pass an agenda, and I believe the he truly believed he was doing the right thing (however wrong it may have actually been). The war is a totally different topic, but on the WTC collapse I rest my case. Planes and terrorists (foreign terrorists, BTW).
