Have Terrorists Dumped Codes for the Internet?

[R. A. Hettinga]

http://online.wsj.com/article_print/0,,SB1032467387859107755,00.html


The Wall Street Journal

September 19, 2002
BOOM TOWN EXCHANGE

Have Terrorists Dumped
Codes for the Internet?

Lee writes: Monday's column1 suggested that those worried about hidden al
Qaeda messages everywhere had seen too many Hollywood spy thrillers. It
tried to point out that the Internet and modern cryptography has, for good
or ill, made relics out of old-fashioned methods of sending secret messages.

Cryptographers call this "steganography;" it is the art and science of
hiding a message in some other communication, so that no one but the sender
and the receiver even knows a message is being sent. There are all sorts of
tales about stenographic communications during war time, such as certain
songs being played on the radio as some sort of signal about troop
movements. Most of these are nothing but urban legends, says David Kahn,
whose history of encryption, "The Codebreakers: The Story of Secret
Writing," is regarded as the definitive work on the topic. (Ask someone at
the National Security Administration something about cryptographic history,
and there is a good chance you will be referred to Mr. Kahn's book.)

Mr. Kahn was in Paris when I was writing my column, and unavailable to be
interviewed. I spoke to him after it ran, though, and he vigorously
seconded the remarks made by Whitfield Diffie. "Terrorists don't need
hidden messages," said Mr. Kahn. "They just go to some cybercafe." And some
readers pointed out that there are many other ways of sending private
communications, such as through simple pay telephone calls using
untraceable calling cards bought with cash.

What prompted the column was the recent action by a federal judge to seal
some of the written motions of Zacarias Moussaoui, who is charged with
being the "20th hijacker." Also, the Bush administration has asked TV
networks not to broadcast al Qaeda speeches, for fear of hidden messages.

Like many Americans, I have been taught to be quite concerned when my
government tells me there is something I won't be allowed to hear or read.
In the case of al Qaeda, does the national security risk justify such a
banning? My argument was that it didn't. It is never possible to do
something without any risk at all. But I don't think the risks associated
with coded messages in, say, speeches are anywhere near as significant as
they would need to be before Americans should be deprived of the right to
listen to them.

Several readers, including some below, suggested I was insufficiently
concerned with the threat al Qaeda poses to the U.S. The Wall Street
Journal's offices are across the street from the World Trade Center; my
colleagues in New York just returned home after a year in temporary
facilities. I don't think anyone at this paper needs lectures about 9/11,
or the fact that al Qaeda members seem to consider the mass murder of
Americans to be a sacred duty.

Finally, one can argue about whether TV networks should or should not
broadcast bin Laden speeches in the first place. One writer, below, says
the speeches shouldn't be on the air or in the papers because we don't want
to provide terrorists with a megaphone. That might be a good reason not to
put something on the evening news, but that wasn't the reason cited by the
Bush administration. I was always taught that one of the great things about
America is it allows even people like Zacarias Moussaoui the chance to have
their say in court. Our entire political tradition is one of trusting
citizens to make intelligent choices about what they hear, and not of
trusting the government to tell people what they should be allowed to hear.
* * *

Like most computer geeks I've known, Mr. Diffie's grasp of the real world
is limited, and it appears you've bought into his drivel. "That is what I
worry about most today," referring to the possibility of the government
using national security to suppress inconvenient speech, is incredibly
ignorant. Maybe he should talk to some of the survivors, or families of
those killed on 9/11, to get in touch with something worth his worry. We
really are at war, in which innocents are getting brutally destroyed, and
fools like Mr. Diffie are almost as bad as the "journalists" who
disseminate their vapid thinking.

Bill Fello
* * *

Leave it to The Wall Street Journal to demolish the crude attempt by the
Bush administration to discourage the American media from reporting the
words of the nation's terrorist adversaries under the guise of "national
security." Your column quoting the inimitable Whitfield Diffie finally put
the lie to the administration's claim that any news medium reporting
accurately and fully on the words of bin Laden and other terrorists would
compromise national security by disseminating "coded signals" to sleeper
cells around the world and the country. I found it interesting that the
Journal did this so well and so authoritatively, since it is, editorially,
in favor of a strong response to terrorism and sometimes seems willing to
compromise certain civil liberties in the interests of security. In other
words, the newspaper has such integrity it will report the news accurately
and fully even if a particular story is not consonant with the paper's
editorial leanings. Virtually every other newspaper (at least the many of
which I'm aware) has already compromised the accuracy of its news reporting
in the interests of its positions on terrorism, the war and the Bush
administration. Bravo, and keep up the good work. In dangerous and often
confusing times such as these, there's no substitute for journalistic
integrity and intelligent, accurate reporting.

Harvey Silverglate
* * *

Would that all we had to worry about, like the complacent Whitfield Diffie,
were government attempts to suppress our communications! His worries seem
rather trivial in light of 9/11, established facts in the study of the al
Qaeda organization and the stated goals of bin Laden and others. To
underestimate the capabilities of the latter and overestimate the sinister
intentions of the current government are the hallmarks of the modern-day,
left-leaning, conspiracy nuts like Mr. Diffie. No doubt you at the Journal
know at least several families who wish all they have to worry about is our
government.

Phil Jamieson
* * *

Your column totally missed the forest for the trees. The Osama bin Laden
"coded messages" the Bush administration wanted to block were in fact
blocked. The "coded message" was a gloating, arrogant Osama bin Laden
preening before sympathetic Islamic people in the U.S. and the world. As
bin Laden mentioned, people follow and cheer the "strong horse" and the
message at the time was "I am that horse, follow me"! Also Mr. Moussaoui's
coded message of "I'll use the infidels' own tools of free expression to
degrade them and promote our jihad" is now justly being blocked. Mr.
Moussaoui and bin Laden are free to say what they will in America; however,
responsible mass media see the forest and do not hand them a megaphone.
Freedom of speech does not preclude responsible journalism that refuses to
freely amplify terrorist causes.

David Finch
* * *

Thank you for your thought-provoking column. I am familiar with Mr.
Diffie's work, but don't want to rely on him for assessments of terrorist
capabilities. I believe a few false positives are warranted until we have a
better assessment of the extent of the terrorist cells in this country.
Missing signals will be very costly in terms of lives and dollars.

Frederick Scholl
* * *

As a Ph.D. student at Syracuse University's School of Information Studies
I'd have to both agree and disagree with Mr. Diffie's characterization of
the possibilities of "embedding code" in "performance." A message can be
sent in many ways. One is to embed code with a prearranged coding scheme.
Another is in the choice of topic and the manner of delivery. That is why
that which appears to be a "rant" is really a stylized version of
communication. It doesn't make sense to us, but it does make sense to the
receiver. This method can also accommodate a more free-form message, which
is a limitation of the prearranged code. For example, the prisoner may have
simply been trying to communicate that an accomplice (unknown to the
police) was able to escape and is now in a safe house or he might be saying
he managed to destroy his code book. Prearranged code does, however, have
the advantage of cutting down of the ambiguity of the message, reducing the
possibility of interpretation.

Dale Thompson


-- 
-----------------
R. A. Hettinga <mailto: rah at ibuc.com>
The Internet Bearer Underwriting Corporation <http://www.ibuc.com/>
44 Farquhar Street, Boston, MA 02131 USA
"... however it may deserve respect for its usefulness and antiquity,
[predicting the end of the world] has not been found agreeable to
experience." -- Edward Gibbon, 'Decline and Fall of the Roman Empire'

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