Jesse V and the paranoids are firing up 911 conspiracy again. Clue in guys:
if you toast a loaded jet into a building, you get all kinds of interesting metallurgy in the results. That doesn't mean thermit sabotage.
And the 'explosions' in some videos are just collapses. But to a rube, every bang is an explosion.
And anyway: its not hallowed ground, except perhaps to the NYC rats that cleaned up the toasted corpses.