I am a pious Scots-Irish Presbyterian Christian and I provide a synopsis and a clue about the 9/11 fall of the World Trade Towers.
Synopsis: The Towers fell fast. It took only 15 seconds -- the same time as for a dropped softball. This astonishing speed forces the conversation: "Cascading concrete slabs engage in successive inelastic collisions.
Reaction (inertial) forces from next-stricken slabs provide the only restraining (fall-slowing) forces. Applied (bracing) forces are absent. Brace-removing explosives are suspect."
A Fortran language program tracks the fall and deepens suspicions about explosives.
Clue: Loose change Google 9/11.