People don't understand how the WTC was constructed. For instance, at the point of impact of the first airplane, the steel I beams outside the WTC were only one quarter inch thick steel. That's because architects have an old adage that the building only has to support the weight of above it. Every time you build a building taller, you are actually sliding a floor underneath the existing weight of the floors above. The outside mesh of the WTC was designed to hold 40% of the total weight of the building.
People don't understand how the WTC was constructed. For instance, at the point of impact of the first airplane, the steel I beams outside the WTC were only one quarter inch thick steel. That's because architects have an old adage that the building only has to support the weight of above it. Every time you build a building taller, you are actually sliding a floor underneath the existing weight of the floors above. The outside mesh of the WTC was designed to hold 40% of the total weight of the building.