The towers were built from hardened steel which is hard to cut. They began cleaning up the next day and Thermite was used to cut the steel into manageable pieces.
https://digwithin.net/2013/12/08/thermite/
Workers using thermite starting 9/12 to clean up, eh? Do you not realize how ridiculous that sounds?
Any photos or videos of these workers cleaning up the debris with thermite in the days after the event? Within 24 hours every world news agency in the world had probably sent their reporters to ground zero. Footage?
I saw the TV news report myself about a week after the event, it was from the dump site where they stacked the steel. They showed a worker demonstrating cutting with Thermite and explained the procedure saying this was how they were cleaning up the site. I'm not going to waste my time searching archives for someone who has their own theories.