“they willingly abase themselves by publicly accepting that a kerosene fire (1500°F) can melt steel (3000°F). The fact that 1500 is less than 3000 is called a “conspiracy theory.”
So you’ve never seen the demonstrations of heated steel becoming more plastic (deformable)? It doesn’t have to melt to fail structurally.
You might also want to review this incident from 2007 - where a gas tanker fire caused a freeway overpass to collapse:
http://www.nytimes.com/2007/04/30/us/30collapse.html
The US government had nothing to do with the 9/11 attacks.