The Wall and 9/11

[erpowers]

I know this issue has been dealt with before but I hope someone will answer my question(s) on this issue. I know that the idea that the wall separating criminal investigations from international investigations caused 9/11 has already been debunked, but I am not clear on the debunking. John Yoo, who worked with the Bush Administration during 9/11, wrote a book, and in that book he tried to claim that the wall was part of the reason 9/11 happened. He claimed that FBI field agents had asked FBI headquarters for a warrant to look at the computer of one of the 9/11 hijackers, but FBI headquarters denied the request using as it reason, the wall.

From what I had heard it had been proven that the wall did not prevent the FBI from capturing the 9/11 hijackers. I have heard various things. One seemed to be that a memo talking about at least one hijacker learning to fly but not wanting to learn to land was sat on until it was too late to do anything. In addition, I have heard that the wall issue was misunderstood by FBI headquarters and that they could have given a warrant for the FBI field office to open the computer. In addition, I have heard something about how when Clinton was in office he tried to change the law so that the government could open the computers of suspected terrorist, but Republicans lead by Donald Rumsfeld, stopped the effort because computer companies were worried about their computer patents or something like that.

So, can anyone give me some help on this issue? Even if you just give me some websites to go to and look up some information. In the meantime I will try to do some research on the computer issue.