I suspect all that an investigation will find is that the Bush administration didn't follow up well on a few leads and hints the 'something' might be afoot. This is well worth knowing and I assume they'd rather NOT have this investigation in an election year, but I doubt that serious malfeasance would be found.

There are plenty issues to accuse the Bushites of without this...still...

(I blame lax airport security as much as anything for the attacks,(how did everyone GET box cutters on airplanes?)...but it is always possible to bypass security. I would imagine that now, almost ANY plane full of people would do what the brave few on that last plane did and stop any hijacking attempt done with knives)