Sure, it might be interesting to note that Zogby's polls of New York City residents show that about half of the people suspect domestic involvement in the mind-numbing events of 9/11. You might say, though, "Well polls are simply measures of opinion!"
However, when top minds of the country form a group to expose the tough truths about the most outrageous crime ever commited on US soil, it is a serious wake-up call. Check out the names & credentials on that list. Then, read this research paper by Brigham Young University physics professor Steven Jones.
The video links of NYC firefighters revelations and footage of the tower collapses are damning enough, but the physical and visual evidence is overwhelming.