Bob Graham's remarks (pre-recorded for the same event as OP's post)
"All of the people who have been in leadership positions of investigations into 9/11 have come away with the feeling that it was implausible to believe that these 19 people, most of whom didn't speak English, most of whom had only been in the United States for, if any, a very brief period of time, could have carried out such a complex operation which required completion of the planning, the practicing, and then finally the execution of the plot."
"If you feel, as I do, that there WAS a network of support for the 9/11 hijackers, what reason do we have to believe that that network was abandoned immediately after 9/11. What reason do we have to believe that it's not in existence today, ready to be used for a future attack against the United States?"
Full press conference of OP's clip:
See Also, eg:
Bandar -- now Abdullah's national security adviser -- said Saudi intelligence was "actively following" most of the September 11, 2001, plotters "with precision."
"If U.S. security authorities had engaged their Saudi counterparts in a serious and credible manner, in my opinion, we would have avoided what happened," he said.
http://www.cnn.com/2007/WORLD/meast/11/01/saudiarabia.terrorism/index.html
Fifteen of the 19 hijackers were Saudi as, of course, was bin Laden. With American airspace still closed, dozens of Saudi royals and members of bin Laden's extended family were airlifted back to Riyadh, most after only perfunctory questioning by the FBI. And just two days after the attacks, President Bush was smoking a cigar on the Truman balcony of the White House with Prince
Bandar, the Saudi ambassador and man about Washington, in the company of Dick Cheney and Condoleezza Rice.
http://online.wsj.com/news/articles/SB10001424053111903480904576512262024552884