From: jdunning@phoenix.Princeton.EDU (John Alan Dunning)
Subject: Re: Wreaking a habitat (was Re: Wrecking a Planet
Originator: news@nimaster
Organization: Princeton University
Date: Tue, 12 Jan 1993 04:10:12 GMT

In article <rwallace.726800959@unix1.tcd.ie> rwallace@unix1.tcd.ie (russell wallace) writes:
>In <1993Jan11.154326.27213@linus.mitre.org> m23364@mwunix (James Meritt) writes:
>
>>In article <rwallace.726538590@unix1.tcd.ie> rwallace@unix1.tcd.ie (russell wallace) writes:
>>}In <1993Jan8.144835.281@linus.mitre.org> m23364@mwunix (James Meritt) writes:

>I'm assuming the attackers and the defenders have the same amount of
>money to spend. For an attack on a planet, the attack is more
>cost-effective, because the attackers can use cheap bombs and even
>cheaper silvered-balloon decoys (or high-speed rocks if you prefer),
>whereas the defenders must build orbital weapons platforms, which being
>in orbit, are very expensive to build and maintain. On the other hand,
>an attack on a habitat must use expensive guided missiles, whereas the
>defenders can build guns relatively cheaply, because the guns are being
>built and maintained right next to the population and industry.

[...]

>>}So what? A weapons systems costs the same amount to build, and nearly
>>}the same to maintain, whether it is on alert 50% or 100% of the time.
>
>>Not into offense/defense systems, are you.  Wrong.  For an example,
>>look at the maintenance costs of an aircraft carrier during flight
>>ops and one in mothballs.
>
>Absolutely. Consider in old-time naval war, the fact that a battery of
>coast-defense guns was much cheaper than a battleship of equivalent
>firepower. The habitat's defenses are like the coast-defense guns, being
>built right next to one's population and industry, and not needing to be
>activated until an attack is in progress. A force attacking a habitat on
>the other hand, would need mobile weapons systems which would incur huge
>costs for constant maintenance.  A moon base would also have relatively
>cheap defenses, but these would cost little less than those of a
>habitat; a coast defense gun costs little more if it needs to be ready
>24 hours a day than if it needs to be ready 12 hours a day. This is of
>course assuming that the defenders of a moon base know what direction an
>attack will be coming from, which is a pretty big assumption. The
>defenders of a habitat don't need to know, as they have a 360-degree
>field of vision and fire.

Why do you insist on making the planetary space-based defenses so
expensive to build and maintain?  Any civilization capable of mounting
significant orbital defenses is going to build them in orbit, not
planetside.  Of course that means there would have to be one or more
habitats nearby to build and maintain the weapons, which would then also
become targets in any attack.  But as long as you're building defenses
for the planet, you might as well build some more for the habitat.
Makes them all cheaper through mass production.  You get a larger
perimeter of detectors, as well.

Also, it sounds like everyone is assuming the civilization will be
based on either a single planet or on multiple habitats.  You're not
going to have habitats without a planet, unless you're colonists from
another system and didn't find any habitable planets in this one (then
why did you come?), or the home planet was rendered mostly
uninhabitable by some nuclear conflagration, or you've turned it into a
giant zoo in some sweeping environmental reform.  You're also not
going to have a planet with orbital defenses without habitats,
precisely because, as Mr. Wallace notes, it's just too expensive.

One of the advantages habitat-supporters claim is that the colonies
can be anywhere in the system that they want and can move around at
will, to confound long-range, unguided ballistic weapons.  But is this
likely?  What are all these habitats doing out there?  How are they
making money?  

Maybe they're growing food for the overpopulated home planet, which is
teeming with 30 billion marching morons.  (Ahh, perhaps there's a way
to combine the two major threads of this group. 8-)  In that case
they'd very close to the planet, to reduce shipping times.  If the
planet is the major source of consumers in the system, the habitats
are probably going to be clustered around it to attract as many of
them as possible.  Are the habitats vacation getaways?  Huge casinos?
No one from the planet, or from other colonies for that matter, is
going to travel to the Oort cloud to spend their hard-earned cash.

The cheapest way to ship (inanimate) products between colonies and 
near-earth obrit would be to use some sort of mass driver to simply launch
the unguided or minimally-guided cargo ships at a big receiving
station of some sort right next to the colony.  (This was how O'Neill
proposed getting ore from the moon to orbit cheaply.)  This system
assumes, of course, that the orbits of the habitats are predictable.
Shipping cargo to randomly jinking habitats is going to be much more expensive.

Perhaps the economy is based mainly on the trading of information,
rather than physical products.  In that case the colonies might indeed
be anywhere.  But their distance from each other would still be
limited by the speed of light.  If the consumers are used to the
near-instantaneous access to information available from a planetwide
network, they'd get pretty impatient if they have to wait 5 or 10
hours to get the information they just purchased.  Again, the economy
would dictate that that the habitats would be clustered around the
home planet or at least clustered around each other, providing
attackers a larger target.

>>And without postulating a technology which would also allow the rock to
>>home in on your habitat, the habitat couldn't dodge.  Use the same engines.
>>And it would be cheap - no need for life support or a lot of the other things
>>needed on a habitat. Face it - a nice place to live is seldom a nice place to
>>fight from - and vica-verse.
>
>If the rock is small, the defensive armament will vaporize it. If it is
>big (which I think you are assuming it to be), the cost of tossing it
>around at those sort of speeds, plus mounting enough defensive armament
>on it to prevent the habitat from launching missiles to destroy it (or
>at least disable its engines), plus the accomodation for the personnel
>to operate and maintain all this equipment, will make it cost a good
>fraction of what the habitat itself cost. Plus, it will be seen coming
>from a long way off, leaving plenty of time for the defenders to do
>something about it, or at least evacuate the habitat, leaving you with
>a trade of a very expensive set of engines, armament and life support
>system, for a very expensive habitat. Not much point, methinks.

This assumes that the inhabitants have somewhere to evacuate to.  The
cost of the "life boats" is also a factor in the placement of the
habitat.  You can make fairly cheap, and therefore pretty
uncomfortable, life boats if you can expect rescue within 24 hours,
say.  Maybe giant beach balls with an air supply and minimal food.  If
rescue times are measured in weeks or months, you're looking at
well-stocked ships, with plent of radiation shielding, food, etc.  So
the cheaper the life boat, the closer the habitats, and thus the
bigger the target.  "Bigger" in the sense that the attacker can more
confidently assume that the habitats in the cluster won't be moving
very far from each other, because the inhabitants want to take
advantage of the benefits of having close neighbors: cheap shipping,
more customers, faster rescues, etc.

In fact, disrupting trade may be all you need to do to take over the
system or destroy its civilization.  If the habitats are clustered
together, throw rocks at them until they disperse and start jinking.
Everything is suddenly more expensive, and the habitats inhabitants
can no longer rely on a speedy rescue if they need to evacuate.  Each
of the habitats now has to make its own spare parts, or do without.
Pretty soon people are feeling kind of lonely and isolated.

If the habitats were not clustered to begin with, what do they do to
make money?  Or are they completely self-sufficient?

>--
>"To summarize the summary of the summary: people are a problem"
>Russell Wallace, Trinity College, Dublin
>rwallace@unix1.tcd.ie

John


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