it all comes down to this...
there is a great deal of evidence out there which makes it sound like others knew about 911 ahead of time, or helped stifle its investigation. there is a great deal of evidence that the 'official story' isn't technically feasible. and, there's a lot of new witness testimoney which points to bombs being used to bring down the towers.
in a few years (as was the case with pearl harbor and JFK), there will be a second investigation, once those who were in power at the time of th event have retired and are no longer able to stifle it. Since the white house had the most to gain from 911 (using terror card to win elections and get legislation/spending they want), certainly they cannot be an objective investigator of the event. Just as Johnson couldn't investigate JFK fairly, just like FDR couldn't investigate Pearl Harbor fairly.
however, once bush retires and another admin gets in, we'll likely see more congressman come fwd with bills to re-open 911. and we already know that 2/3 of americans polled want a new investigation, and historically, these big events are investigated later.
so all we can do it watch, and vote for ppl who want to investigate it. it'll be a moot point - we'll own afghanistan and iraq, the goal of 911 - but it'll be nice for the victims, and for america so we don't fall for the BS again.
So either you want an investigation, or you don't. It won't happen tomorrow, but it will happen eventually.