In a sign of the national importance of their meeting, President Bush cleared his entire schedule on Thursday to join Vice President Dick Cheney for a joint meeting with members of the National Commission on Terrorist Attacks Upon the United States, also known as the “9/11 commission.”
The central question for members of the commission is, "What did the president know, and when did he know it?"
That question was made famous three decades ago during the Watergate hearings by Republican Senator Howard Baker Jr., but it is just as important today as officials seek to learn if the 9/11 attacks could have been prevented.
A private, joint meeting with the commissionThe commission had originally sought separate testimony from the president and vice president. But the White House later insisted they would appear together, prompting critics to suggest that the White House wanted to make sure they kept their story straight.
White House communications advisor Dan Bartlett told NBC News it is "silly to suggest" that is the reason. Instead, administration officials said the joint session was desirable because Bush and Cheney were in separate locations on Sept. 11. The leaders were in constant contact and a joint appearance would provide the most comprehensive accounting of the day’s events, they said.
Their testimony will not be under oath, but White House press secretary Scott McClellan said they will "tell it exactly how it happened." He also noted that he expected the president, not Cheney, to do most of the talking.
The president himself was asked twice during his recent news conference why he and Cheney would appear together. "It's a good chance for both of us to answer questions that the 9/11 commission is looking forward to asking us, and I'm looking forward to answering them, " the president said.
Likely questionsMembers of the commission will likely grill the president about the intelligence memo from Aug. 6, 2001, titled, "Bin Laden Determined to Attack Inside the United States." The president received the top-secret memo while vacationing at his ranch in Crawford, Texas.
The president has insisted the document had "nothing about an attack on America. It talked about intentions, about somebody who hated America — well, we knew that."
Bush said he would have "moved mountains" to prevent the Sept. 11 attacks if he had had any specific warning that a terrorist attack was imminent.
National Security Adviser Condoleezza Rice publicly testified that the memo was a "historical" statement rather than any specific warning of an attack.
Structure of meetingThe president and Cheney will meet the commission in a private session beginning at 9:30 a.m. EST at the White House with the 10 members of the commission.
The testimony will not be recorded, nor will a stenographer be present to make a formal transcript. Rather, commission members may take detailed notes during the meeting.
That is different from the commission's interviews with former President Clinton and former Vice President Al Gore, which a commission member told the Associated Press were recorded.
McClellan said the session will not be officially transcribed because the White House considered it a "private meeting" in which highly classified information would be discussed.
"Let's keep in mind that it is extraordinary for a sitting president of the United States to sit down with a legislatively created commission," said McClellan.
The White House interviews are one of the last steps for the commission which plans to issue its final report this summer in the midst of the presidential campaign.
Norah O'Donnell is an NBC News White House Correspondent.