as you can see in the videos, most of the jet fuel ignited outside of the buildings.
What are you basing this on? It is fairly obvious the fuel tanks were breached when the planes hit the building, but it is logical to assume the majority of the fuel was carried inside the bulding before leaking out. Jet fuel is a hydrocarbon and as such would create a large fireball with very little fumes as a fuel source.
jet fuel does not burn very hot and burns very quickly. the steel components were certified to ASTM E119 specs. this means the steel would have had to be exposed directly to a 2000F fire for over 2 hours before any damage would occur.
First of all, you are correct in that jet fuel openly burns at a temperature around 550F. However, the fires in the Twin Towers were not burning openly, they were enclosed. Once the inside of the buildings caught fire (which would happen rather quickly given the bulding was soaked in burning jet fuel), the internal temperature of the burning floors would have been elevated in excess of 1100F. Additionally, the wind at that height would have fanned the fire and elevated the internal temperature even higher.
As the temperature on these floors rose, the structural steel and concrete that held the bulding together would heat up. Concrete used in buildings does not have the fireproofing used in tunnels, as it is not expected to be exposed to burning hydrocarbons. As such, the concrete holding the bulding would weaken at temperatures exceeding 1000F (which is well below the average internal temperature of a housefire). The structural steel girders have a critical temperature of 2066F. However, this is not the minimum temperature for steel to weaken, it is the temperature in which it begins to melt. Obviously, the steel would expand as it heated and start to lose its structural integrity.
after the initial blast, the steel would have been exposed to about 500F fires. not even close to what would be needed to implode and pulverize 2- 110 story structures. if you think airliners caused the implosions of the 2 towers then you explain to me how and even stronger building like #7 imploded. lol... you cant.
House and building fires do not burn at 500F, they increase to 1100F in approximately 3.5 minutes. Coupled with the wind and burning jet fuel and the structural damaged caused by a 767 crashing into it, the concrete and steel that held the buildings together failed and the tower fell. Once you research the actual properties of these materials, it really isn't rocket science.
It is obvious you have done little to no research on the effects of fire on steel, concrete and buldings, yet continue to make ridiculous claims that there was some type of government conspiracy to explain the towers' collapse. Additionally, you have failed to provide any kind of motive as to why these alleged conspirators felt crashing a plane into the towers would not be enough to terrify the American people. Next time try using Google before parroting out whatever nonsense they claim on your favourite conspiracy website that week. The "facts" you are citing are not based in any type of reality.