You are asking for facts about a future hypothetical — it makes no sense. The guys in caves is silly. Are you talking about Osama Bin Laden, the billionaire family fellow as a “guy in a cave.” Sloppy thinking.
So, if al quaeda is not in a cave, where are they? We are by far more rich and powerful than OBL and his crew (or are you arguing differently?) Our being richer and “more powerful” would not have prevented 9-11. Technology would not have prevented box cutters on planes, unless we were willing to fully screen every person who had access to the planes prior to flight - we had the capability in 2001 to prevent those coming onto planes. Technology was not the problem. We did not see the threat.
Your arguments make no sense.