The writer attempts to uncover and reveal certain things that "they" (he never really says who "they" are, possibly the voices in his head) don't want you to know. He attempts to offend liberals, conservatives, big business, religious people, and just about everyone in his book.
Some things are actually interesting, like the fact that Hitler has living relatives in the US.
Most things are flat out sensationalized: "An FBI testifeid that lie detectors don't work" - 1 out of thousands of FBI experts said that, OH MY GOD CALL THE NEW YORK TIMES!
One is flat out dishonest and encourages defrauding the postal system by offering ways to cheat them.
My final response is that the book is mildly entertaining and interesting.