Now that’s a letter you don’t want to get. The Pentagon’s top lawyer has written to the author of the upcoming book about the top-secret raid that resulted in the death of Osama bin Laden to threaten legal action Thursday. The book, which wasn’t vetted by government agencies, is “in material breach and violation of the nondisclosure agreements you signed,” said the letter obtained by Reuters. The author is a former Navy SEAL known by the pseudonym Mark Owen, who issued a statement saying he has not disclosed confidential material that would compromise national security. Legal action may be the least of the author’s worries—his real name and photo were posted on an official al Qaeda Web site last week after being revealed by Fox News.