As recently as the late 1960s, the very existence of the National Security Agency — the Fort Meade-based defense organization that gathers intelligence from foreign countries — was such a closely held secret that insiders jokingly called the place "No Such Agency."
So when a New York newspaper reporter named David Kahn stood ready to illuminate it in a big new book in 1967, the government was less than pleased.
"According to my editor [at Macmillan Publishers], the NSA director flew up to New York to say it would be dangerous to national security, and unpatriotic, to publish it," says Kahn of his book "The Codebreakers," the 1,200-page blockbuster that would establish him as the world's leading expert on the history of cryptology, the art and science of making and breaking codes.
Kahn, now 80, has only expanded on that reputation, and he hasn't slowed down much, let alone retired. But he has decided to downsize, and when it came time to decide where to leave the research materials he has amassed over the years, he chose the agency he once hauled into the light.
Last month, the NSA announced it had added the David Kahn Collection — complete with more than 130,000 pages of original interview notes and 28,000 books — to the library of its public anteroom, the National Cryptologic Museum. The gift nearly doubles its capacity as a research site.
"For those who care about cryptology — what it is, how it works, where it fits into world history and culture — at some point, [they'd] want to look at the Kahn collection," says curator Patrick Weadon, who took part in a ribbon-cutting ceremony in October. "It's an eclectic cornucopia of all things cryptological."
To Kahn, his decision was no more ironic than the nature of his work. It's odd, if you think about it, spending a career spotlighting the work of professionals to whom secrets matter more than anything — odder still if you can gain their respect along the way. But then, Kahn has always been a little bit different.
It isn't everyone who can pinpoint the moment his or her life took its future shape. Kahn can. It happened when he was 13, strolling past the public library in his hometown of Great Neck, N.Y.
A book lay in a display case, and the title caught his eye. " 'Secret and Urgent!' Did that draw me in!" he says in a phone interview from Great Neck, where he still lives.
Kahn devoured the breezy work (its subtitle: "The Story of Codes and Ciphers"), his mind reeling at how the author, a man named Fletcher Pratt, laid out some of the classic processes for breaking ciphers.
He loved the subject — he joined the American Cryptogram Association, even wrote letters to the so-called father of American cryptology, an Army pioneer named William H. Friedman — but never guessed it could be big enough to give rise to a career. "I'm lucky," he says. "I never had to grow up."
His love became requited in 1960, when Kahn was a reporter for Newsday, the Long Island-based daily, and a sensational story broke. Two young codebreakers for the then-ultra-secret National Security Agency, William Hamilton Martin and Bernon Mitchell, decided they opposed U.S. spying policies and defected to the Soviet Union.
Kahn contacted editors of the New York Times Magazine to propose a "backgrounder" — a freelance piece that would shed light on the event, including a longer look at the NSA. The article ran in 1961, and three publishers contacted him with offers of a book contract.
Kahn wrote 160 pages, he says, before he realized he hadn't finished his first chapter. He spent much of the next six years compiling a history of codes and codebreaking that reached as far back as the hieroglyphs of ancient Egypt, incorporated the American Civil War, and used exhaustive interviews with analysts to illuminate the world of spying from both sides of World War II and the Cold War.
His notes from that book alone might have made a contribution to history. It was the first time anyone had attempted such a comprehensive look at a topic that had seemed shadowy and hard to follow.
"David made the critically important subjects of cryptography and cryptanalysis [code-making and code-breaking, respectively] understandable, interesting and even compelling," William Crowell, a former deputy director of NSA, told Newsday in 2004. "Before he came along, the best you could do was buy an explanatory book that usually was too technical and terribly dull."
"The Codebreakers" became an international best-seller, was considered for a Pulitzer Prize and was translated into others languages, including Arabic to Serbo-Croatian. It also landed Kahn on "The Tonight Show," where his jocular appearance helped catapult his subject into the mainstream.
Orson Bean, subbing for host Johnny Carson on March 11, 1968, allowed that, like millions, he'd always loved the decoder rings Ovaltine offered as promotions, but he wondered aloud whether cryptology wasn't an esoteric pursuit for "strange birds."
Kahn didn't miss a beat. "Are you kidding?" he said. "They got 14,000 people down in Washington doing this. [It's called] the National Security Agency. It's bigger than the CIA!" The transcript is part of his collection.
Motel to museum
For many years, a seedy motel stood at the intersection of Route 32 and the Baltimore-Washington Parkway, a half-mile from NSA headquarters. Known as the Colony 7, it was a favorite lunchtime haunt for American cryptologists, many of whom reportedly used to wonder, half in jest, how many enemy agents had rented rooms there.
If that was an inside gag, it seemed the NSA wanted to write a punch line. It bought the building in 1990, and three years later started the National Cryptologic Museum there. Today, about 50,000 visitors a year check out the free attraction, which has been gaining wider attention in travel guidebooks as a hidden cultural gem.
One of its draws: The museum appeals to the earnest and the quirky alike. Students of spying history can operate a German Enigma coding machine from World War II or read declassified transcripts from the Venona project, the top-secret NSA operation that identified Americans who were spying for the KGB, the Soviet Union's NSA equivalent. Pop culture fans can see displays like the exhibit on hobos, who long ago developed a graffiti system by which to relay information when they rode the rails.
"The museum has some of the most secret pieces of equipment America has ever possessed," Kahn says. "It's one of the great, underrated collections in the Baltimore-D.C. area. And unlike, say, the Smithsonian, you can see the whole thing in a couple of hours."
His collection is a natural fit. The thousands of books Kahn donated include light reading ("Secret Writing Tricks," "Encyclopedia of Espionage") and historically significant tomes such as "The Elements of Cryptanalysis," the seminal William Friedman work the Army used to educate generations of cryptologists.
Auditors have set the books' value at upward of $60,000, Kahn says. Many are available elsewhere, but his collection puts them in one location for the first time.
Then there's the rarer stuff, like the original edition of Johannes Trithemius' 1518 book "Polygraphie," the first work ever published on cryptology, and a framed letter from Napoleon to his son, Eugene, that asks the prince in June 1806 to continue "sending me letters [by] the archbishop of Silesia from Rome to Dresden" because "the [deciphering] key has been found so that they can be read just like ordinary writing."
"One of [Kahn's] key achievements has been showing the public that [cryptology] has been with us since the beginning of time," Weadon says.
He has included manuscripts and various editions of his own five books, including "Hitler's Spies" (1978), "Seizing the Enigma: The Race to Break the German U-Boat Code" (1991) and "The Reader of Gentlemen's Mail" (2004), Kahn's study of a larger-than-life American character, Herbert O. Yardley, who took command of the nation's first cryptological team, MI-8, in 1917.
An Indiana-born math genius, poker hustler and occasional screenwriter, Yardley all but personified the tarnished-hero image many have of those who deal in espionage. After the U.S. government disbanded his operation as a cost-cutting measure in 1929, he got his revenge by writing a tell-all, "The American Black Chamber," which hit the 1931 best-seller lists and outraged the intelligence community.
Yardley's portrait hangs in the museum's Hall of Honor exhibit ("These Were the Giants," reads a sign above the pictures), a visual statement of the grudging respect he still commands. Thanks to Kahn, visitors can now flip through a manuscript of his blockbuster.
Looking for a story
Encryption "is a method for taking a written document [plain text] and transforming it to a unreadable document [cipher text] so that the original document is somehow recoverable from the cipher text," according to Partha Dasgupta, a computer systems professor at Arizona State University.
There are two possible ways of solving that cipher, Dasgupta writes: by "brute force" (running through every mathematically possible solution) or by cryptanalysis, an infinitely subtle science that can draw on mathematics, computer science, linguistics, engineering, inductive reasoning and more to narrow the range of possibilities.
NSA cryptologists must keep their work secret, of course, and their approaches can be so complex as to defy easy description.
How did Kahn do it in his books? "I went about it as though it were a newspaper story," he says. "I followed the leads, the footnotes, from one source to another. It's a technical subject, but if you want to show the effect the subject has, which I did, you end up writing about people. I was looking for a good story."
In Kahn's case, that meant so much research that he all but created his own archive, one that included all the interview transcripts, government documents, articles and other materials he used to write his books.
In the mid-1960s, when Kahn was reporting for "The Codebreakers," most of the history-altering cryptologists of World War II were still alive and possessed of their memories. Many were being interviewed for the first and, as it turned out, last time. A great number are now dead. Kahn kept copious, well-organized notes on every conversation.
That's what makes his thousands of pages of interview transcripts so valuable, says Rene Stein, the museum librarian charged with cataloguing the collection. "No one else did research this comprehensive and thorough, and in many cases, it can never be done again," she says.
Stein leads a visitor to a back room — the old kitchen of the motel, as it happens — and nods toward a row of tall gray crates. "Every one of those is full," she says with a sigh. She has catalogued about 55 boxes' worth, indexing each interview separately.
Within a couple of years, she hopes, she'll have completed a Kahn center in which visitors can find any transcribed conversation they're interested in with relative ease. In the meantime, when scholars call from Sweden, Poland or Great Britain — as they often do after attending a Kahn lecture — she can usually ferret out the information they're seeking within a few days.
Kahn couldn't be happier with how things have gone. As recently as five years ago, his home in Great Neck was overrun with his stuff. It took museum representatives a half-dozen visits with a pickup truck before things started looking different.
Now that more than 90 percent of the material is in place at Fort Meade, he can do something he has been planning for a while: move from his home of 30 years to an apartment in Manhattan, where he'll soon be working on his next book.
The conflict between Kahn and the NSA was short-lived. For one thing, the author agreed, after much discussion, to omit some of the most sensitive material from "The Codebreakers" before it was released. For another, as time passed it was hard to argue with his results.
"[Kahn] is the world's premier authority on code-breaking," Adm. Stansfield Turner, former director of the CIA, said in the 2004 Newsday article. "His work is of tremendous help in understanding history — that of warfare and diplomacy, in particular — as well as the world we live in."
Whatever its thinking, the NSA made Kahn its scholar-in-residence in 1995 and brought him back as a featured speaker for its 50th anniversary celebration in 2002. "Who'd have thunk I'd be here?" he said to open his talk.
When it was over, more than one audience member sought him out to say, in effect, that Kahn was their own Fletcher Pratt, his first book their "Secret and Urgent!"
"I read 'The Codebreakers' and decided to go into codes," he remembers one young cryptologist saying. "You changed my life.' "
The Kahn collection could change a few more.
If you go
What: The David Kahn Collection
Where: The National Cryptologic Museum Library, 9900 Colony Seven Road, Annapolis Junction
Hours: 9 a.m. to 4 p.m. weekdays; 10 a.m. to 2 p.m. the first and third Saturdays. Library hours vary. Call 301-688-2145 to ensure a staff member will be available.
Information: 301-688-5849 or nsa.gov/about/cryptologic_heritage/museum/