Again, I read Trumps comments as nothing more than, when you are in a leadership role, anything that happens on your watch is your fault.... or more simply the buck stops here.
This isn’t controversial, this is 101 leadership.
All the rest of this as far as I’m concerned is just nonsensical white noise.
Trump is correct that if effective immigration enforcement had been in place, at least some of the terrorists would not have been in this country:
http://www.fairus.org/issue/identity-and-immigration-status-of-9-11-terrorists
I don’t think anyone, even Mr Trump has suggested at a functional standpoint that Bush caused 9/11.. obviously the terrorists caused 9/11...however when something happens on your watch, and you are in charge, its your responsibility one way or another.