Christian, from what I understand there have been times in U.S. history when surveillance lists have existed for certain books being checked out of libraries. Hate literature, Nazi stuff definitely. I want to say that this was even a thread in a Tom Clancy novel, but its been years since I've read any of them, I could be wrong. Given the current state of world affairs, I wouldn't be surprised if there were currently some books that get a person red-flagged on a list somewhere. However, the internet has probably made such a list obsolete in regards to library books, so maybe its just an online thing now, or both.