A very quick summary in 2:23. And of course you have the various trufers out there refuting this also.
I'd like to inject a point. Hundreds of years ago, the Chinese were smelting Iron on hardwood fires stoked with oxygen via bellows. See Wikipedia. Those offices were full of hardwood and other combustibles, not just jet fuel. Also note in the videos of the towers after being hit but still standing how quickly the black smoke was exiting those high floors and moving sideways, not up. It's going to take a strong wind to do that. There is your bellows. It was damn hot up there. Personally even hot enough to melt the central steel pillar imo - though I've never heard anyone suggest that.