I can't think of a more effective way for terrorist cells to communicate than thru the library system. By using checked out library books, one could encrypt a message by circling a word on a precribed page sequences, then returning the book to be later checked out by a terrorist cell.
I believe the FBI is onto something here. Possibly learned from some loose lipped captives at Gitmo (Cuba).
That is a stretch me-thinks. Pretty clever but if these guys can come and go as they please (as they obviously can) what makes anyone think they can't buck the library ID process and check books out under assumed identities? This tactic will be of very limited use to the investigations and will only serve to further our slipery slope decent into fascism.
EBUCK