In the years since September 11, 2001, amateur plane spotters around the world have tracked the movements of what started out as an unidentified flying object, a phantom jet. The plane, a Gulfstream V, the kind of small, sleek private aircraft favored by movie stars and business executives, was first spotted in October 2001 in a remote stretch of the Karachi airport. Eight weeks later it appeared at Stockholm’s Bromma Airport, then at a military airfield in Jakarta. Last fall the London Times reported that the plane had flown to some fifty destinations outside the US, from Guantánamo Bay to Egypt, Jordan, Iraq, Morocco, Afghan-istan, Libya, and Uzbekistan.
In December The Washington Post revealed that the plane is registered to several persons who do not exist—fictitious names, post office boxes, and Social Security numbers. The plane is used, the Post explained, for “rendition”—the relatively new tactic employed by the CIA and the Bush administration to move detainees from one country to another for interrogation. The Gulfstream facilitates a kind of race to the bottom, whereby suspects are whisked out of countries that are reluctant to use torture as an interrogation technique, and into countries that have no such inhibitions.
The chance sightings of this mystery plane are an apt illustration of the occasional and fragmentary glimpses that civilians get of the vast realms of American military and intelligence activity that are secret. According to the Information Security Oversight Office of the National Archives, which monitors American classification policy, the American government created over 15 million secrets in 2004—or some 40,000 individual classification decisions every day. When occasional slips occur—the sighting of the Gulfstream V, the leaked photographs from Abu Ghraib—we come to appreciate how much of what our government does we simply cannot fathom.
The linchpin of the classification system and the device that allows government secrets to stay secret is the code name. Every program, exercise, and operation has a code name. Individuals, offices, and enemies are all granted code names. Only those who are cleared to know certain information will know a code name, and the higher the clearance, the more extensive one’s code vocabulary. Indeed, so Byzantine is the classification hierarchy that even the different levels of clearance to know secret names have secret names of their own. Thus, William Arkin points out in his new book Code Names, in the months after September 11, 2001, those at the Pentagon who had a security clearance for information that was marked Secret could not gain access to information that was Top Secret. But those cleared merely for Top Secret often did not realize that there was an even higher level above that, known by the code name Polo Step. “Polo Step was used to confine highly sensitive Iraq and counter-terrorism war planning to a small circle,” Arkin explains.
In June 2002, Arkin published the fact that there was a code name called “Polo Step” for Iraq war planning in …