The Risks Digest

The RISKS Digest

Forum on Risks to the Public in Computers and Related Systems

ACM Committee on Computers and Public Policy, Peter G. Neumann, moderator

Volume 10 Issue 82

Tuesday 29 January 1991


o Re: Patriots: SDI, etc.
Dave Parnas
Nathaniel Borenstein
Phil R. Karn
Hans Mulder
o Re: Patriots and electronic cash
Karl Kluge
o Re: Electronic cash completely
David Lamb
Larry Nathanson
Randal L. Schwartz
K. M. Sandberg
Peter da Silva
Richard A. Keeney
o Info on RISKS (comp.risks)

Re: Patriot Missile (Agre, RISKS-10.81)

Dave Parnas <>
Mon, 28 Jan 91 23:21:58 EST
Phil Agre <> asked for comments about the "Patriot"
missiles.  There seem to be people around who are trying to exploit events in
the Gulf War to revive SDI.  Let's look at his remarks one at a time.

>"The Patriot missiles genuinely seem to be working well, at least in the
>desert environment."

Actually, we have very little information about how well they are working.  We
know that they have had some successes and some failures but we have no idea
how many Patriot's have been fired for each SCUD shot down.

> Yet a few years ago the Patriot was the very prototype of the incompetent
>high-tech military development program.  Its testing in particular came in for
>congressional ridicule.  What happened?

Among other things, it has been given a particularly easy job.  It was
originally developed as an anti-aircraft system, not an ABM system.  In many
ways the job of a terminal phase (point defense) ABM system (for incoming
missiles or warheads in unpowered flight) is much simpler than the
anti-aircraft task for which Patriot was first developed.  Aircraft can take
evasive action and use sophisticated devices to fool systems like Patriot.
Older missiles such as the SCUD can do neither.  I suspect that the Patriot is
still not very effective on its original target, manned aircraft.  The SCUD is
an ideal target for the Patriot.

As far as I can determine the key to the Patriot is the launcher, which has a
sophisticated Phased Array Radar that can track incoming objects, backed up by
a computer that can predict the future path of the object (assuming that it is
not powered or steered).  This is a rather simple job.  The Patriot has an
operator to determine whether an object being tracked is friend or foe and
designate a target.  The Patriot missile itself is launched on a path that will
intercept the path of the incoming missile (another simple application of
physics) and has a very simple homing system that is effective when (and if) it
gets near its target.  Were the target missile to change course drastically
after launch, the Patriot missile would end up somewhere else.  Some reports
indicate that some Patriots have missed their targets and ended up where they
did damage to the buildings that they were supposed to protect.  (These are
unconfirmed reports.)

>According to its manufacturer and to various other experts quoted in the
>press, its software was greatly improved through the application of software
>technology developed for SDI.

The design and production phase of the Patriot was completed in 1980, and the
missile went into operational status in late 1984.  Flight tests of the Patriot
started in 1974.  The development and manufacture tooling stage of the Patriot
was completed in 1980, the year before Reagan took office.  The SDI program was
not announced until 1983.  There was no SDI software technology to be applied
to Patriot.  In fact, I believe the reverse was true.  SDIO funded Raytheon to
see if the Patriot ideas could be used for the terminal phase components of
SDI.  If there was technology transfer, must have been from Patriot to SDI.
Remember that SDI funds were to be used for "research" on the space-based
shield; they were not to be used for improving other weapons.

>These experts regard the success of the Patriot as evidence that the
>SDI's software nay-sayers were wrong.

Those experts had better go back and read what we "software nay-sayers"
actually said.  The objections that were raised were to the space based aspects
of the system.  I, and others, repeatedly said that the only place where
something could be done was the terminal phase for the defense of important
(hardened) targets.  Terminal phase defense systems like Patriot can operate
without the elaborate communication and synchronization that was envisaged for
SDI and do not have to automate the decisions that would have to be automated
for the space-based system.  Terminal defense systems can have an operator who
makes decisions that would have had to be automated in the space-based system.
The range of terminal defense systems is rather limited and they cannot prevent
the warheads of the incoming missile from detonating if intercepted.  For SCUD
missiles that carry conventional armaments this is not a serious problem.  For
the threat portrayed by SDI supporters it was a fatal weakness.  Patriot is
subject to all the known limitations of terminal phase defense systems.  For
example, the maximum range is reputed to be 70km and the effective range is
reduced if the launcher is not near the projected impact point.

We should never forget that the Patriot was about 19 years in development.
(Remember former President Reagan's generous offer not to deploy SDI for 7
years!)  The SCUD was first deployed about 1965 - Patriot about 19 years later.
All RISKS readers should think about the advances that we have seen in 19
years.  It should come as no surprise that the Patriot can sometimes destroy
missiles that were deployed when its development began.  The interesting
question is what it would do against aircraft and modern weapons.


Patriots: Reprogramming, SDI implications

Nathaniel Borenstein <>
Mon, 28 Jan 1991 15:16:04 -0500 (EST)
I heard this weekend on NPR that American & Israeli technicians are furiously
working to reprogram the Patriots to be "more intelligent about people on the
ground."  It seems that nothing in the Patriot's programming informs it about
the population (or lack thereof) in the area.  The NPR report was unclear on
what the differential actions would be, but I presume that it might have
options regarding the moment of interception, and is being reprogrammed to
favor intercepting when not directly over a populated area.  Aside from being
amazed that this was never taken into account in the first place, I'm awestruck
that they're willing to reprogram the Patriot -- which seems, after all, to
basically work -- right in the middle of the war!  I know I feel like I'm
living dangerously even when I install a new binary in peacetime...

On the subject of "Does Patriot prove SDI could work?"  I think the answer is a
clear and resounding no.  First of all, the Patriots can't even hit all the
SCUD missiles.  Letting 1 of every 10 SCUDs through is a big success, but
letting 1 of 10 Soviet nuclear missiles in would be a disaster.  Second, the
SCUD is a relatively slow missile that follows a fixed trajectory; it would be
useless against anything that can take evasive action, such as a Cruise
missile, and you'd probably need some sort of AI-like techniques to predict the
future trajectory of a Cruise taking evasive action.  Finally, I heard an air
force officer explaining on CNN the other day that the Patriots may never again
be as useful as they are being in this war, because "now that their
capabilities are known, it will be trivial to make the next generation of
missiles able to fool them.  Basically, in this game all the cards are stacked
in favor of the offense."  In other words, we're very lucky that the Patriots
are so well suited to the current situation, but we'd be foolish to extrapolate
wildly to future situations, and particularly to SDI.

Re: Patriot (RISKS-10.81)

Phil R. Karn <>
Mon, 28 Jan 91 20:24:19 EST
Ever since the first successful Patriot intercept over Saudi Arabia, I began
waiting for the SDI crowd to being crowing. I didn't have to wait long - Louis
Rukeyser on PBS's Wall Street Week last Friday was one notable example of
engaging mouth with brain in neutral.

But no reputable critic of SDI ever said that a system like the Patriot could
NEVER hit missiles fired singly or in small volleys that target relatively
small areas, carry conventional high explosive warheads, and lack some fairly
obvious countermeasures.

Yet despite the relatively easy targets presented by the Iraqi SCUDs there have
already been quite a few failures of the Patriot to destroy them, and several
cases where the Patriots have themselves apparently caused damage to the cities
they are supposedly protecting. I wouldn't exactly use the phrase "genuinely
seem to be working well" when night after night I see TV footage of missiles
(incoming SCUDs and/or errant Patriots) producing unmistakable explosions when
they hit the ground in Saudi Arabia and Israel.

If the SCUDs launched at Israel over the past two weeks had been carrying
nuclear weapons (which is, after all, the original SDI scenario), northern
Israel would now be a smoking ruin -- Patriots or no Patriots.  Even the
Pentagon admits Patriots are of little use against SCUDs armed with chemical
warheads since they would merely disperse the chemical over the target.  [...]


Re: Patriot missiles

Hans Mulder <>
Tue, 29 Jan 91 18:16:26 +0100
In Risks 10.81 Phil Agre writes:

> The Patriot missiles genuinely seem to be working well, at least in the
> desert environment.

Actually, a bug was discovered last week.  Apparently, Patriot launchers
can operate in two modes: fully automatic and human-in-the-loop.  They
have been exercised in human-in-the-loop mode for several years now, and
work rather accurately that way.  But the Patriot launchers defending
cities in Isreal and Saudi Arabia are currently running in fully automatic
mode, primarily on the ground that they can react a few seconds faster
that way.  In contrast, the Patriot launchers defending Incirlik Air Base
near Ardana, Turkey, reverted to running in human-in-the-loop mode after
it was discovered that a bug in fully automatic mode causes the machine to
occasionally launch two missiles for no reason (they are always launched
in pairs -- presumably because they are so reliable :-} ).

A Ministry of Defense spokesperson explained: ``We can't afford to waste
these missiles: they cost $600,000 a piece.''
I haven't seen such a thorough risk assessment for years...

Hans Mulder

Re: Risks 10.81 (Patriot missiles and electronic "cash")

Mon, 28 Jan 1991 21:13-EST
1) No one, but no one, that I am aware of ever seriously suggested that it was
impossible to construct software to do terminal interception of ballistic
objects. That is a gross distortion of the arguments over SDI software. The
idea that the success of the Patriot has any impact (sic) on the issues
involved is false.

2) I have seen the electronic "cash" proposal before, and yes these people are
serious. My basic philosophy is that the government should have to justify to
me why I ought allow them to keep data on me. The idea behind this proposal is
that I somehow have to justify to the government why they shouldn't have data
on me -- the old "if you have nothing to hide, it shouldn't bother you"
argument. Given what we know the government is capable of (remember J. Edgar
Hoover, or Nixon's "dirty tricks" squad?) to try to reassure people by saying
"Governmental agencies...would be subject to the same Constitutional constrints
that currently exist...for the granting of wiretaps" is a joke. Almost makes me
want to buy a gun and join the NRA.

Karl Kluge (

Re: Electronic cash completely replacing cash (RISKS-10.81)

David Lamb <dalamb@umiacs.UMD.EDU>
Mon, 28 Jan 91 15:39:10 -0500
Hmm.  I know this isn't or talk.politics, but...  In addition to the
obvious RISKS reasons to resist this one, I imagine any serious proposal would
get tremendous opposition from fundamentalist Christians, demanding (at least)
an exemption for religious reasons.  There's a prophecy in Revelations about
"the mark of the Beast" without which one could neither buy or sell.  There was
tremendous furor about Social Security numbers when they were first introduced,
from the same group, for the same reason.  This proposal is a lot more like the
Mark than SSN's were.

And of course, one exemption would breed others.

David Alex Lamb

Re: Electronic cash completely replacing cash (`witt', RISKS-10.81)

Larry Nathanson <>
28 Jan 91 22:37:57 GMT
>        If all the people who do business in cash were forced to
>report their incomes accurately - if the under-ground economy were
>forced to the surface - the Government could collect an additional
>$100 billion a year for the nationl treasury - without raising taxes.

How is the author so sure of his figures, if this is money that has not been

>        How do we create a system to keep cash businesses honest ??
>Eliminate cash.  That may sound revolutionary, but the exchange of
>cash for electronic currency is already used in nearly all legitimate
>international business transactions.

Define "honest".  If every store complied with every last OSHA regulation, most
small businesses couldn't afford to stay in business.  Sometimes small
businesses skirt the rules slightly so as to be able to stay in business.
There won't be much of an increase in tax revenue, if the letter of the law is
enforced so strongly that no business can survive.

>        Think about it.  Drug deals, muggings, corruption, businesses
>concealing their income - they all require cash and secrecy.  A
>monetary system bases solely on electronic currency would leave a
>trail that would cripple such enterprises.

Just because the listed illegal acts all require secrecy, does not mean that
all secret acts are illegal.  If I share an account with my wife, and we both
have instant access to every last dime, I can't throw her a surprise party or
really be at the bar drinking, when I told her I was at the office.  What about
minors?  Do they have their own card?  Do their parents get to see their
accounts?  Or are they just not allowed to have money?

>        Then, all the new currency would be returned by its owners to
>the bank of their choice.  All banks would be required to open
>accounts, free of charge, to all depositers. (Banks would surely be
>delighted to provide this service at it would result in increased

Tell that to my bank.  I get hit for around $8 a month just to have an account.
It costs money to maintain the information.  If everything was completely
dependent on this system, as the article states, then it would cost more to
maintain the information.  No bank in their right mind would let me keep a $20
account without a monthly.

>        In place of paper money, we would receive new cards - let's
>call them Americards - each bio-mechanically impregnated with the
>owner's hand and retina prints to insure virtually foolproof

What about those who don't have hands?  Or retinas?  Or neither?  If I buy a
pair of socks, I have to be fingerprinted, and put my eye to a machine?  (BTW-
great way to spread conjunctivitis)

>        The Government would supply all homes and businesses, free of
>charge, with machines, to read the card, certify the holder's
>identity, and make instantaneous electronic debits and credits.
>Regardless of what such machines would cost, the Government, with $100
>billion in new revenues and no more printing and mining costs, would
>come out ahead.

Hmmm..  a combination MS card reader, full hand finger print analyzer, retina
scanner, computer, and modem, supplied to every individual that wants one.
This is supposed to save money over green ink on white paper?

>        And think of the benefits to the average American.  No one
>would have to write a check again.  Bills could be paid electronically
>from home.  Such a system is already available through banks and
>businesses on a limited, optional basis.

And that's the way it should be.  On an optional basis.  What if I WANT to
write a check?  What if I'm going to mail a check to someone, so that by the
time it gets there, it will be payday, and I'll have money in my account?
Instantaneously paying bills from home is great, IF you want to pay them that

>        For example, on payday, instead of receiving a paycheck, your
>salary would be electronically transferred into your account.  At
>lunch- time, you would go to your favorite resteraunt - or the local
>hot dog stand -and instead of paying cash, you'd use your Americard.
>You'd get a receipt instantly and could get a cumulative record from
>you bank (or your personal computer) as often as you like.

And the hot dog vendor can see how much money I've got in my account?  Every
last hot pretzel vendor on the streets of NYC is going to have a MS card
reader/retina scanner/fingerprint analyzer?  (Not to mention a generator to
keep it running)  Some of these guys can't afford the wood to burn under the

>        The benefits would be tremendous.  Individuals and businesses
>would no longer be able to conceal income.  All transactions would be
>recorded in a computerized bank file and would be easy for the I.R.S.
>to check.  Muggers and buglars would be out of business: no one would
>be carrying cash and stolen property would be difficult to sell
>because there would be records of all transactions.

Money purely man's invention.  If people can't get access to 'real' money, then
they will find something else of value, and trade it instead.  Gold, Silver,
Platinum, and everything else of value would have to be banned.  Not to mention
barter.  This wouldn't even put a dent in illegal activities.  But on the other
hand, Joe's wife could notice that he bought a 24 pack of condoms, the day
after she left on a business trip.

>        Fugitives would be easier to track down, legal judgements
>easier to enforce, illegal aliens simpler to spot, debtors unable to
>avoid their responsibilities by skipping town.  The census wouln't
>overlook households.

I'd say the odds on it magically reducing tooth decay are better than the odds
on it fixing any one of the above problems.

>        And there would be no information on the Americard computer
>that doesn't already exist in other forms today.  If anything, our
>rights to privacy would be more secured with the protections that the
>Americard would offer.

I fail to see the logic underlying that statement.

>        And besides, I'd like to ask every parent whose child walks to
>school through a gauntlet of drug dealers, everyone whose home has
>been robbed, whether they think that their rights have been
>jeopardized by a system that could solve all these problems ??

In other words, in order to prevent crime, we should radically change the
economic structure of our country.  Instead of Americards, how about just
switching to communism!  In the Soviet Union only drug problem is alcohol, and
the muggers are shot in the streets.   It would be a LOT cheaper just to elect
the communist party than to muck around with all this technology stuff.  Maybe
there are some things that Americans hold more dear (like freedom and privacy)
than things even like safety.

>        Since computer systems occasionally fail, Americard would be
>contained on several connected secure computers: at the local bank
>branch, the main bank, the regional office of the Federal Reserve and
>the Federal Reserve in Washington, D.C.

And making the system more complex would tend to reduce problems and increase

>        Americard may seem like a drastic approach but its advent is
>inevitable.  In the days of the telegraph and the pony express, who
>could have imagined that one day there would be a phone on every
>street corner in Manhattan ??

Poor analogy.  There are many inventions and ideas that never made it off the
drawing board.  This will be another.

Larry Nathanson . 726 Comm Av #5J . Boston, MA 02215 . 617 266 7419

Re: Electronic cash completely replacing cash (`witt', RISKS-10.81)

Randal L. Schwartz <>
Mon, 28 Jan 91 15:49:21 PST
[...]  I'd hate to see this system in place.  I'm not a luddite, but replacing
moveable tokens for ones and zeroes that are necessarily manufactured and
replicated at will is opening up a whole bunch of issues all at once.  We don't
have the authorization/authentication technology far enough along and cheap
enough to do this on a national scale yet.

And, are you really going to give every man, woman, and child a smartcard?
"Here's your allowance junior.  Oops!  The cardreader is broke.  Well, I guess
you're not getting one today."  And what about the gazillions of vending
machines out there?  Are you going to make those invalid overnight?

A suggestion I had seen was that there'd be small "currency" valid for amounts
under, say, $100.  Banks (or corner vending machines) would provide for
transfers between your smartcard and some "currency".

I think we're getting closer to this compromise forced not by government
mandate, but by economics.  Bills over $100 haven't been printed for quite some
time, because most legitimate uses of those bills have been replaced with EFT.
I'm using cash less and less each day.  I pay nearly all of my daily expenses
with my Visa card.  In fact, the local Burger King and Seven-Eleven stores take
Visa now!  I write checks to pay my bills through the mail, although many
pay-by-phone services exist so that I wouldn't even have to do that.

And not one part of this is by government mandate.  Economics have pushed the
gradual phase-in of the cashless society.  And it's happening quite gradually
and rather nicely, thank you.

Just another cash-kinda-guy,

Randal L. Schwartz, Stonehenge Consulting Services (503)777-0095 ...!any-MX-mailer-like-uunet!!merlyn

Electronic cash completely replacing cash (RISKS-10.81)

K. M. Sandberg <>
28 Jan 91 21:16:18 GMT
The worst part about this is that I am sure that the author believes what is
said, yet fails to understand the risks involved. True, it would get more tax
dollars, but at an unknown cost for all the machines and networks to make it
work. What do you do if you lose your card since nobody will trust you without
it? With cash at least you can put some aside in case of emergency, but with
only a card that may decide to not work it is all or nothing.

It also assumes the the barter system does not exist, after all who would
exchange items for work. Unless you then take inventory of all the items that a
person bought, just to make sure.

Of course the line of "if you are honest, why should it bother you" is bound to
come up. This means that "honest" people would not mind having cameras watching
them all the time since it would cut down on crime, then you could tatto
everyone so that there is no doubt about identification. And so it goes,
welcome to 1984 by Orwell.

Was this in the editorial or opinion section at least? Also what does it take
to get people to think about what they are saying, or to just plain think?



Peter da Silva <>
Tue, 29 Jan 1991 00:46:28 GMT
>    Think about it.  Drug deals, muggings, corruption, businesses
> concealing their income - they all require cash and secrecy.  A monetary
> system bases solely on electronic currency would leave a trail that would
> cripple such enterprises.

And, of course, let others flower. How well would a cashless economy have
prevented the S&L scandal? And, of course, the government would have to call in
all the precious metals again. This would just make it easier for the rich...
with easily liquifiable assets in the form of stocks, bonds, real estate, and
so on... at the expense of the poor and middle class.

And that's without considering the possibility of fraud in the system itself!

Re: Abolish Cash

Richard Keeney <>
Tue, 29 Jan 1991 00:11:30 CST
When I read the artical "Abolish Cash" by Harvey F. Wachsman, "The Government"
appears to be the only safegard in his proposed system.  Many people would
agree with me when I bring up the point that we still have not devised a good
method of completely safeguarding ourselves from the various forms of
government that are necessary to run our society.  A system where the
appropriate legislative body has such absolute control over trade and
enterprise would seriously undermine the population's ability to remove such a
body from power when they no longer agree with that body's policies or
activities.  I would assert that "cash" provides a significant safeguard of our
right to freely assert our political views, especially in the face of
disagreement from those currently in power.

I will go even further and point out that such a legislative body would find it
almost impossible to resist making full use of the level of control offered by
such a system, and would certainly find many innovative ways to make us regret
giving them so much control.  There are many historical examples of how even
the best intentioned use of legislative power can go bad.  Not only do we have
no reason to trust "The Government" with such a system, but we have many
reasons to mistrust them.

Another weakness of such a system that I would like to point out relates to the
inability of such a system to deal with all the seemingly small but necessary
transactions required to "grease" the machine to make things move smoothely.  I
can imagine that people would become obsessed with every little penny.  When
you have to take the trouble to make an official "transaction", people will
become less generous with things like gratuities, informal loans, small gifts,

Such a system would be very cruel (perhaps even to the point of violating our
constitutional right to be free from cruel and unusual punishment) to somebody
who is denied access to their money due to a lost or damaged card, an error, or
red tape.  One day everything would seem fine, and the next, wham! "I am sorry
sir, but we cannot accept your Americard due to a hold placed by agency
Red_Tape_Is_Us relating to a delinquent payment of $0.39.  By the way sir, you
can clear that up with them on Mondays between 2:00 and 3:00 PM (excepting
national holidays of course) if you fill out form 55-A-1-55-92194 in triplicate
and have a note from your mom."

I would also like to point out one area that would be very similar to credit
cards that would require additional thinking.  What happens when there is a
dispute over a charge between a merchant and a customer?  Who would have the
onus of proof?  What about when a merchant has to have a person's account
number to post a running series of transactions as in the case of a hotel, for
example?  It would be tough to imagine Uncle Sam eating those disputed amounts
like credit card companies often do to keep the good will of both the card
holder and the merchant.  Truth in advertising would also continue to be a
problem.  How do you know what charge will appear on your card when you put it
into a vending machine or give the number to some mail order merchant?

Finally, I think "Americard" may already be registered as a trademark by
somebody (Ameribank sticks in my head).

Richard A. Keeney, Senior Software Engineer, Management Graphics, Inc.,
1401 East 79th Street #6, Bloomington, MN, 55425      Phone:  +1-612-851-6126

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