Check the timeline...the info wasn't passed in 1999, on Bill Clinton's watch--which is exactly why the Dims will (ultimately) decide to take a pass on this one. Digging into this matter raises a lot of disturbing questions about Clinton's cuts in the intelligence budget, and that infamous "wall" that panel member Jamie Gorelick created between the counter-intelligence and law enforcement communnities.
As a political matter, I'd say go for it, just to make the Democrats squirm. But as a practical matter, I don't think we'd learn much from this. Clearly, there were massive cooperation problems between intelligence and law enforcement before 9-11...this "revelation" proves what we already know...