I haven't seen the PDB yet, but according to CNN, the report contains a fact that is going to save President Gump's ass:
A report that at least 70 FBI investigations were under way in 2001 regarding possible al Qaeda cells/terrorist-related operations in the United States.
(link)
I think Dear Leader can plausibly say that with 70 FBI investigations going on, it looked to him like a lot was being done about the Al Qaeda problem. Seventy investigations does sound like a lot.
Of course, Dear Leader can still be faulted for not following up, but that position is tainted by hindsight.
And this does not rule out the possibility that Dear Leader was warned in other ways, such as through tips from foreign intelligence services (link).
As a believer in the LIHOP Hypothesis (Weak Version), I tend to the view that counterterrorism was a low priority for Bush because the PNAC/Vulcans were itching for a reason to attack Iraq. They knew that a terrorist attack of some sort was practically inevitable, even if they made counterterrorism a high priority. Why not wait for the inevitable attack, and use that as the catalyst to remake the Middle East? After all, the official PNAC position is that for America to find the resolve to transform the world according to PNAC's plan, a new Pearl Harbor might be required. They probably though the attack would be overseas (like the Cole) and would have a relatively small number of casualties, less than 100. Regretable, but necessary, to launch the Middle East Initiative.
They were probably shocked by the events of 9/11 and realized they really screwed up. But they sure got their excuse to invade Iraq.