For once I really can't blame Bush. For him to return to the White House before it was clear that the attack was over would have been stupid and dangerous. In fact, Bush probably couldn't have returned if he had wanted to. The Secret Service probably ordered him to remain under military security until the situation was under control.
By the same token, Cheney hiding for most of the day was probably a good idea. Worse yet, it's absurd to blame Colin Powell for happening to be out of the country when the attack happened.
Jay