"...getting a warning that Muslim or Arab terrorist groups are interested in hijacking American planes is roughly equivalent to being 'warned' that bears are 'interested' in crapping in the woods. This is the normal state of things."

Excellent point.

The problem with 'warnings' that the FBI, CIA, etc. may have received and should have acted on is that (1) they are frequently very general and vague and rather obvious, such as above, and (2) they are so numerous - literally thousands of so-called warnings about scores of terrorist organizations are received and analyzed each year.

It's perfectly fine to make rational suggestions about enhancements to the future coordination between national security and intelligence organizations, but to even remotely claim that Bush should have known and could have done anything thing to prevent Sep. 11 is, frankly, assinine.