AE911Truth are insisting that thermite & conventional explosives are sufficient to account for all the building collapse effects. Here at this link:
http://www.ae911truth.org/images/articles/2015/Aug_2015/FAQ-15b.pdf
they offer a massive review of the works by all the popular nuclear advocates. It's a very credible effort, though I don't find it completely persuasive. They don't consider the possibility of aneutronic fusion devices, and I don't feel they've completely explained the dust production, or the high temperature effects seen in the dust. On the other hand, I don't have much to offer in response to their explanations for the tritium levels found at ground zero, or their explanation of barium & strontium & other trace elements in the dust samples. AE911T also claim that all the early-responder cancers can be explained by toxic chemical effects; I don't have the expertise to say. The opposing argument (in Prager's work) seems to be based on anonymous sources.
Niels Harrit thought that the amount of thermite required to bring down the towers would've been in the hundreds of tons, but Derrick Grimmer's original work said 11 tons. With directed thermite shaped-charges such as discussed in the above video, the amount required might have been even less.
Overall, the case for any necessity of aneutronic cold fusion or some other exotic technology at the WTC on 9/11, is looking much weaker than before.