After any 9/11 anniversary, I get edgy around people who think the Towers falling was an "inside job." They post meme's like this one to try and convince the unknowlegeable that there is a hidden and more complex reason why they fell. They never try to take into account Occam's Razor to explain why.
I am going to straighten the record out in clear, plain and unmistakable language that a 3rd grader can understand.
First rest off, the Towers were basically giant Jenga towers. Perfectly stable as they were built and designed to withstand "off-axis forces," such as an aircraft impacting the building, a massive hurricane or even an earthquake. The Towers were also meant to withstand an out-of-control fire for up to three hours as well so everyone could get out safely. The Towers DID survive the impact of the aircraft.
Second, the base steel used (there were 12 types) in the construction was A36 steel. That grade of steel does indeed melt at 2,750 degrees, and jet fuel does indeed burn at 1,500 degrees.
But that's not the whole truth.
A36 steel (which has a structural strength of 36,000 pounds per square inch) does indeed turn into a liquid at 2,750 degrees. However at the lower temperature of 1,500 degrees, it loses half of its structural strength, well below the temperature that it becomes liquid. There were also other materials burning in the fire as well. Such a conflagration would have caused an updraft, which would have somewhat raised the temperature and increased the intensity of the fire.
Again, the designers of the tower anticipated an event with the same effect in their design, so that the Towers would stand long enough to get everyone out safely. What they didn't anticipate was that the aircraft would dislodge the layers of fire protection covering the structural members. This allowed the heat to get to and soften the structural members.
The result is like when you pop a balloon full of air or water. As soon as that one section of the balloon is punctured, the structure of that part of the balloon fails and transfers it's load to what's left. This is what happened in the Towers. A couple of structural members were destroyed by the initial impact. The surrounding uncompromised members became soft and weak from the heat of the fire because the insulation was knocked off and the heat could get to the steel. Once the weakened structure members became soft enough that they could no longer hold the weight on them, the members failed and dumped that stress and weight to the unaffected structural members. They now had more stress and weight they could handle and snapped. Because that's what A36 steel does when it's stressed with over 36,000 PSI.
When the overloaded floors snapped, they dumped the entire load of the upper building onto the next lower floor. This caused the lower floor to "pancake," suddenly squishing out all of the air, windows and loose items from that floor, making it look like there had been an explosion. This cycle repeated for each floor until all of the now-rubble came to rest.
Now, if you think the Towers were "a demolition job," watch this video:
Watch the time, work and planning it took to successfully drop that building. If you think that kind and scale of work can go on for a couple of weeks or months without anyone noticing, you're an idiot.
Another thing to consider, was how it was possible for two barely-trained pilots to hit a very specific spot perfectly to cause this whole chain of events? If the aircraft had hit too high or too low, the Towers might not have fallen. This is why Occam's Razor beats any massive conspiracy.
When you want to decide and go public on something, please have all of the facts in proper context before you blindly offer someone else's opinion.