Mr Arkin broke the story of a classified report detailing hurdles to an Iraq invasion. That was back before the war started. His book lists 3,000 military code names and details the operations the names goe with. Mr Arkin believes excessive government secrecy led to the government being unable to stop the 9/11 attacks. He considers his book a protest against that kind of secrecy.
Those sorts of things can make you a lot of enemies. And the faked cable is pretty detailed. It merges false charges with a knowledge of where he was and what he was doing at key times. It's filled with military jargon and follows closely the way a real Defense Intelligence Agency report would appear and be circulated.
Mr Arkin has written for the Los Angeles Times and the Washington Post's online edition. He's also been an Army intelligence analyst, so he's familiar with these sorts of cables. That had him firing off a letter to Defense Secretary Donald Rumsfeld, saying in part:
"Such an action raises deeply troubling questions about the integrity of the department's processes and raises the possibility of an organized effort to intimidate me as a journalist."
The faked memo was leaked to the media in an apparent attempt to discredit Mr Arkin on the eve of the Iraq invasion anniversary. (WashPost)