Re: Lesson from Yes Minister
"No self-respecting terrorist (well: one who hopes or expects to walk away from an "incident") would give up the goods that easily and therefore the only data they will collect will be from harmless individuals and private citizens with no nefarious intent."
AIUI, the terrorists who flow into the WTC made no effort to hide the identifies. So these measures would have been ineffective anyway as no one joined the dots.
Or maybe they did, and let it happen. /tin-foil-hat