"The Killing Star" - R-bombs and interstellar genocide

[SpaceMarine93]

I recently came across an old, obscured hard science fiction book by Charles R. Pellegrino and George Zebrowski called "The Killing Star". The book was published in 1995 and had since gone out of print. It's a little dry, and have a few flaws like a few scientific mistakes and inadequate characterization, but the ideas in which it presented makes it realistic and grounded.

But the main selling point of the book was the terrifying solution to the Fermi Paradox concerning alien life.

Set in 2076, Humanity in the Solar System is experiencing a golden age of progress and peace, thanks partly to significant scientific advances in technologies such as virtual reality, nanotechnology, genetics and space travel. The way to interstellar travel was open by means of STL antimatter powered Valkyrie starships which allows Humanity to reach the stars. All seemed well.

And then everything went to Hell.

Suddenly, without warning, a massive swarm of relativistic kill vehicles, or R-bombs, suddenly emerged from interstellar space and systematically impacted on Earth and every Human settlements across the Solar System. In one, single decisive attack, most of Humanity was destroyed, and the rest of the book follows the survivors hiding across the Solar System in a bleak, desperate struggle for survival as the spaceships from the alien civilization that launched the missiles move in to finish the job, all the while trying to figure out WHY the aliens would pull such a horrific act of genocide on them.

The book dissented many assertions by scientists back then such as Carl Sagan which suggested aliens who became sufficiently advanced without destroying oneself would become peaceful, and therefore not a threat to Human civilization. What is terrifying is that the book presents a case where it would actually be coldly, brutally logical for any intelligent civilization to exterminate any neighbor who became advanced enough to contact with other alien life.

The logic centers around three assertions which the authors argued any intelligent lifeform in the universe, regardless of how different, would fundamentally follow:

A) A species would place the survival of its own ahead of any other species

B) A species that comes to dominate the planet would be, in addition to intelligence, be vigilant, ruthless and aggressive whenever it becomes necessary.

C) The above two laws applies to any other species in the universe.

The minimum requirement, according to them, for being able to make meaningful contact with other alien lifeforms would be developing the technological ability to sent objects at high Relativistic speeds, which in the book is achieved by means of antimatter spacecraft. The book argues, and as many science fiction novels had already suggested, any spacecraft that could reach relativistic velocities could also double as an extremely powerful weapon of mass destruction by laws of physics. Thanks to travelling at the speed of light it is extremely hard to detect, nearly impossible to intercept and could wreck destruction on a scale that would eclipse just about any weapon Humanity had ever conceived, and several types of natural disasters.

In short, with an R-vehicle an alien civilization can effectively and thoroughly destroy any other alien civilization with a single strike, as the aliens had done to Humanity in the novel. And worse, referring back to the assertions made by the authors above, it becomes logical for an alien species to exterminate its neighbours that possess such an ability since no alien species can logically accept such a risk of such vehicles being used on them - the risks are simply too high, made worse by the fact that one cannot entirely be certain what the opponents are thinking, and one misstep means extinction by a hostile civilization. The only way to be absolutely sure is, in essence, "Do it unto others before they do to you".

As the aliens in the story eventually pointed out to some survivors, in the end it was nothing personal.

For a better summation of the points, refer to:
http://www.projectrho.com/public_html/r ... lling_Star

One argument had been made that if a third party alien civilization observed one alien civilization exterminating another alien civilization they would know that the first alien civilization is hostile and mark them for extermination in kind, thus rendering the whole genocide point moot, but I disagree; an alien civilization that frequently exterminates other civilizations via R-bombs would know that the risks applies to themselves, and take measure to hide themselves and their activities from the rest of the universe and other alien races; shutting down any signature or energy emissions from their homeworld, disperse across the stars into hidden colonies, moving their relativistic missiles via slower, low energy means to another star system before firing them off. Any civilization who knows how to build relativistic space vehicles would know this as well and make efforts to do the same.

Plus, the genociding alien civilization could just simply exterminate the third party alien civilization too if they found out.

So the terrifying solution to the Fermi Paradox is this - they are out there, but they are killing each other off with effective genocide weapons, and the rest are now either hiding, not advanced enough, or thoroughly exterminated.

And it begs the question: should we follow the same route and become a race of paranoid, secluded genocidal killers as well to ensure our own survival in a universe where interstellar extermination could be easily achieved? Or worse, maybe that route is inevitable and we are pretty much destined to become that, or be exterminated.

Now, should Humanity shut down SETI as they suggest or is there a catch to the whole premise?

[Ford Prefect]

The whole premise rings hollow to me. It presents itself as supremely rational, even though its logic is that the only logical response to a supposed risk is complete annihilation of literally everything that might look at you funny. Their three assertions also don't strike me as being fundamentally valid, particularly a). It's actually really easy to say that, but I don't think it would necessarily reflect reality when it came to the crunch (at least these days). That's just gut feeling, mind.

[Simon_Jester]

The fundamental proposition is wrong. There are a lot of reasons why relativistic missiles fired over interstellar distances aren't sure-fire antiplanet weapons.

There are also a lot of reasons why, for an advanced civilization which had easy space travel and the capability to build relativistic interstellar missiles, having a dinosaur-killer missile smash into the homeworld would be only a mild inconvenience. And would absolutely guarantee revenge.

For that matter, deflection missions to stop an incoming relativistic missile are credible unless we assume soft-SF technology... sure, you may only have a few weeks' warning, but you know exactly where the missile is supposed to go and where it's coming from, so throwing shrapnel in its path isn't exactly hard.

[Connor MacLeod]

Its 'rational' insofar as the assumptions behind it hold true. As the Atomic Rockets page mentions, this only works if there is only one other hostile race out there potentially capable of harming you (or if you get lucky and strike them all.) because if you don't get them all you've just announced you're there to anyone you DIDN'T get and that you are hostile.

And that's really the problem with the premise. Its basically very paranoid and hostile and well.. militant. 'strike first, because otherwise THEY MAY STRIKE AT YOU.' is all logical and shit, but would you argue it as good international policy, for example, on our own world? I don't think it would work out in that case.

And you could literally invent any number of scenarios to argue it back or forth, so I'm not sure hypotheticals are all that convincing anyhow.

[SpaceMarine93]

The fundamental proposition is wrong. There are a lot of reasons why relativistic missiles fired over interstellar distances aren't sure-fire antiplanet weapons.

There are also a lot of reasons why, for an advanced civilization which had easy space travel and the capability to build relativistic interstellar missiles, having a dinosaur-killer missile smash into the homeworld would be only a mild inconvenience. And would absolutely guarantee revenge.

For that matter, deflection missions to stop an incoming relativistic missile are credible unless we assume soft-SF technology... sure, you may only have a few weeks' warning, but you know exactly where the missile is supposed to go and where it's coming from, so throwing shrapnel in its path isn't exactly hard.

But would the defenders be able to throw a counter-shrapnel of sufficient power to change the incoming projectile's course? In the novel the missiles hit the Solar System at 92% the speed of light, while the most advanced Human starships the Valkyries are stated to at best travel at around 12% the speed of light. The power difference would be in several magnitudes, would it? (Sorry, my math and physics' are not good). As a matter of fact it was Humanity achieving such speeds (via Anti-matter spacecrafts) that was one of the reasons why they were marked for extermination in the novel - I think the aliens would want to kill them before they could push that % up any higher.

Its 'rational' insofar as the assumptions behind it hold true. As the Atomic Rockets page mentions, this only works if there is only one other hostile race out there potentially capable of harming you (or if you get lucky and strike them all.) because if you don't get them all you've just announced you're there to anyone you DIDN'T get and that you are hostile.

And that's really the problem with the premise. Its basically very paranoid and hostile and well.. militant. 'strike first, because otherwise THEY MAY STRIKE AT YOU.' is all logical and shit, but would you argue it as good international policy, for example, on our own world? I don't think it would work out in that case.

And you could literally invent any number of scenarios to argue it back or forth, so I'm not sure hypotheticals are all that convincing anyhow.

Well, then again we can't exactly apply international policy between Humans to aliens who are probably fundamentally different biologically and psychologically from Humanity in many ways, save perhaps being Apex predators. Plus, a key staple of the concept is that no species interested in its survival cannot afford to be wrong, and then there's the Prisoner's Dilemma getting in the way.

I for one surely hope that the premise is wrong/flawed. It's terrifying believing we live in a hostile universe, especially when considering that it may already be too late for us to do anything with all those emissions we are broadcasting. And then there's METI...

[GrandMasterTerwynn]

The fundamental proposition is wrong. There are a lot of reasons why relativistic missiles fired over interstellar distances aren't sure-fire antiplanet weapons.

There are also a lot of reasons why, for an advanced civilization which had easy space travel and the capability to build relativistic interstellar missiles, having a dinosaur-killer missile smash into the homeworld would be only a mild inconvenience. And would absolutely guarantee revenge.

For that matter, deflection missions to stop an incoming relativistic missile are credible unless we assume soft-SF technology... sure, you may only have a few weeks' warning, but you know exactly where the missile is supposed to go and where it's coming from, so throwing shrapnel in its path isn't exactly hard.

But would the defenders be able to throw a counter-shrapnel of sufficient power to change the incoming projectile's course?

Absolutely. The incoming missile's own stupendous velocity means that anything it collides with will have about that relative velocity ... which means that any interception device placed into the path of the missile will effectively hit it with similarly stupendous energies ... even at quite modest masses. For example, using the site's own KE calculator, we can determine that a 64 kg interceptor (the mass of a modern ballistic missile interceptor,) moving with minimal velocity of its own, will impart some 8.883E+18 joules of kinetic energy (equivalent to an explosive device with a yield in excess of two gigatons) upon colliding with the relativisitic kill vehicle.

Its 'rational' insofar as the assumptions behind it hold true. As the Atomic Rockets page mentions, this only works if there is only one other hostile race out there potentially capable of harming you (or if you get lucky and strike them all.) because if you don't get them all you've just announced you're there to anyone you DIDN'T get and that you are hostile.

And that's really the problem with the premise. Its basically very paranoid and hostile and well.. militant. 'strike first, because otherwise THEY MAY STRIKE AT YOU.' is all logical and shit, but would you argue it as good international policy, for example, on our own world? I don't think it would work out in that case.

And you could literally invent any number of scenarios to argue it back or forth, so I'm not sure hypotheticals are all that convincing anyhow.

Well, then again we can't exactly apply international policy between Humans to aliens who are probably fundamentally different biologically and psychologically from Humanity in many ways, save perhaps being Apex predators. Plus, a key staple of the concept is that no species interested in its survival cannot afford to be wrong, and then there's the Prisoner's Dilemma getting in the way.

We can. A species can be reasonably expected to perform actions within the context of its own survival. When you choose to wipe out neighboring civilizations willy-nilly, you're taking the gamble that there isn't anyone more powerful than you watching ... since they might be reasonably expected to put an end to your rampage by killing your civilization. Also, any civilization that doesn't learn the lesson of how to get along will likely have either blown themselves up in civilization-ending global thermonuclear war, or driven themselves into extinction due to self-induced environmental collapse ... all of this well before the point that they could seriously consider lobbing fractional-cee missiles at their neighbors.

[Simon_Jester]

But would the defenders be able to throw a counter-shrapnel of sufficient power to change the incoming projectile's course?

Since the enemy is singling out enemies that could conceivably build a relativistic missile, I would bet on the target having such capability.

In the novel the missiles hit the Solar System at 92% the speed of light, while the most advanced Human starships the Valkyries are stated to at best travel at around 12% the speed of light.

At those speeds, if the relativistic missile encounters a 0.2-gram projectile (such as a frozen pea), it will suffer effects comparable to a direct hit from a ten kiloton bomb. This will probably be enough to kill it, or at least knock it off course.

A civilization capable of building starships capable of "only" 0.12c can throw a lot of frozen peas if it wants to.

Also, a relativistic missile that builds up to "only" 0.24c (achievable speed for one of these ships if it doesn't have to worry about slowing down; you'd get better than that if you don't have cargo) might in some ways be just as dangerous as the 0.92c missile, especially if it is built large and heavy.

Well, then again we can't exactly apply international policy between Humans to aliens who are probably fundamentally different biologically and psychologically from Humanity in many ways, save perhaps being Apex predators. Plus, a key staple of the concept is that no species interested in its survival cannot afford to be wrong, and then there's the Prisoner's Dilemma getting in the way.

Thing is, the cost of being wrong by hiding and trying to cautiously scope out the universe and get a sense for what it's like out there is much lower than the cost of being wrong by being a murdering asshole who suddenly discovers that he's actually a small fish in a big pond, and that his attempt to murder a slightly less advanced civilization has attracted the hostile attention of a far larger and more powerful one that he can't hope to defeat.

Also, in case you were not aware, game-theory concepts like the Prisoner's Dilemma were invented to describe international policy among humans, that's where the mathematicians got their funding from.

[On a side note, it's kind of disturbing the way you capitalize "humanity" in this context, like you've got that IndrickBoreale93 conceit going again]

[Formless]

Now, should Humanity shut down SETI as they suggest or is there a catch to the whole premise?

What, you mean stop looking passively for interstellar radio signals, transmitted both intentionally and incidentally? That we should end our passive search for planets within their star's habitable zone? That we should stop passively looking for objects of extraterrestrial origin, including solar scale infrastructure, launch facilities for vehicles, and interstellar rockets?

Oh, wait. You don't know what SETI is, do you.

Search for Extraterrestrial Intelligence is largely a (say it with me) passive affair. All The Killing Star argues against is what we call "active" SETI; that is, sending out signals of our existence to other civilizations to make their own search easier. But there are many other aspects to SETI that are unaffected, such as the scientific search for planets, which conveniently yields data that can also be used to find Dyson Swarms (you look for a certain infrared signature that's distinct from the usual dust clouds surrounding stars). In fact, if we take the argument seriously, the argument gives us great reason to double our efforts to find other civilizations and potential weapons targeting us. Because the problem is, we have already been sending out tons of incidental transmissions such as television, and multiple intentional radioglyphs. Furthermore, if we find a civilization which has constructed a Dyson Swarm, we should make efforts to contact them. We plainly pose no threat to their existence, but at the same time can benefit from their protection until we too can create such defenses and move our population off Earth. The argument pre-supposes that there is no such thing as an interstellar police you can appeal to, but that's not true, and their existence cannot be hidden like radio transmissions can.

But its not like such a work of fiction should be taken seriously in the first place. The idea of relativistic weapons spits in the face of physics, and believe me physics can spit back. In a previous discussion among the problems that came up was how are you launching it? A physical "gun" launcher is no more realistic than a solid shell around a star (hence why I always call them Dyson Swarms). The alternative is powering it with an interstellar engine, like an antimatter rocket... which we can spot and identify by the exhaust plume and radiation signature. Plus the whole friction problem means you may not have to throw anything in front of it anyway. The interstellar dust between stars may be all it takes to turn an R-bomb into a plume of harmless gas halfway between us and the idiots who launched it. And of course, you have to account for future civilizations who haven't yet achieved the ability to take you on, but can see exactly what you did to that planet (incidentally, this means that The Killing Star doesn't solve the Fermi "Paradox" *). So do you shoot every planet in range that lies within its habitable zone? That's a shitload of planets! Are you sure you don't want to make a Von Neuman Self Replicating War Probe instead like in Berserker? Because that would be a lot easier to pull off by comparison, and that requires multiple speculative technologies all by itself!

* And of course, I must add as usual that I'm not convinced that there is a paradox at all here. I think its more a product of our own impatience with the process. We hadn't even figured out how to find planets, let alone civilizations, and here's Enriko Fermi asking why we haven't found any!

Which brings up a problem that even applies to the more generalized form of The Killing Star's argument which doesn't hinge on R-Bombs. Any kind of interstellar attack will take centuries to thousands of years to bear fruit. Are we really supposed to believe that a civilization so shortsighted as to harbor extreme xenophobic hostility has the patience to see such an attack through? Or the coordination to get its entire species to work together on this attack? War is a paradoxical activity, in that it requires both great conflict and great coordination. Over long periods of time (again, centuries and millennia) , the people you are most likely to come in conflict with are the people close to you, not the ones lightyears away.

[SpaceMarine93]

Well, then again we can't exactly apply international policy between Humans to aliens who are probably fundamentally different biologically and psychologically from Humanity in many ways, save perhaps being Apex predators. Plus, a key staple of the concept is that no species interested in its survival cannot afford to be wrong, and then there's the Prisoner's Dilemma getting in the way.

Thing is, the cost of being wrong by hiding and trying to cautiously scope out the universe and get a sense for what it's like out there is much lower than the cost of being wrong by being a murdering asshole who suddenly discovers that he's actually a small fish in a big pond, and that his attempt to murder a slightly less advanced civilization has attracted the hostile attention of a far larger and more powerful one that he can't hope to defeat.

Also, in case you were not aware, game-theory concepts like the Prisoner's Dilemma were invented to describe international policy among humans, that's where the mathematicians got their funding from.

Huh, haven't thought of that.

[On a side note, it's kind of disturbing the way you capitalize "humanity" in this context, like you've got that IndrickBoreale93 conceit going again]

Sorry, force of habit. Dammit, I thought about how I had been acting in the forum during the months I had gone, and I was trying to avoid that!

[Ahriman238]

I believe we've had this conversation before (certainly it was old by the time it was brought up again in the Mutineer's Moon thread) and the book itself provides a decent counter-argument. Is simple survivial worth forever hiding from the rest of the universe, and the genocide of anyone who discovers us or might be a threat? Shouldn't any creature with the scientific acumen to reach the stars aspire to be more than animals pursuing ruthless survival of the fittest?

Try the second video.

The best thing, narratively, to come from the killing star is that if you need a motive for a sci-fi villain race, you can have them believe in this premise. Assuming you want to do an exclusively evil race, which has it's own problems.

[Connor MacLeod]

I think the things that strike me about this scenario (which actually came up in the last HARD sci fi debate Formless mentioned) is that there's always the assumption that other civilizations are neccesarily going to be as 'monkey like' as we are (EG basically assholes.) which leads to the assumption that humanity must become the STL IMPERIUM OF MANKIND in order to survive (EG ruthlessly genocide everyone else preemptively or in response.) despite the fact doing so would involve a certain cultural, economic/industrial, and military mindset to pull off (hence my IoM analogy, a combination of fanaticism, nationalism, militancy and outright paranoia.) and even if you do it may do more harm than good.

One of the more amusing scenarios that floats around in my head is that if a future 'humanity' were to actually engage in this sort of practice you'd have to preemptively target every potentially habitable planet in the galaxy, which may pretty much nullify them as any potential for growth (depending on how brutally you 'kill' them, of course.) If that's the case, then you may end up having civilizations that end up becoming effectively spaceborne - eg abandoning Earth and living in manmade colonies of one kind or another (insert your favorite approach here.) Heck I'm pretty sure there is a non-trivial segment of hard-scifi-dom that advocates the idea that orbital colonies and such are MORE 'realistic' than living on planets, as it does away with that pesky 'gravity well' idea. Such a premise might actually make you harder to 'kill' via kinetic impactor if you're colony is reasonably mobile. Of course any civ that could live in space could do the same, and if they can make giant interplanetary doomweapons they probably can coexist in space too, so they would be likewise immune.

And if there is nothing to fear from such attacks, then going to the waste of energy and resources to preemptively kill the galaxy on the off chance you might save yourself (rather than piss someone off and make them retaliate as discussed before), then the scenario itself kinda falls flat.

As I said what the outcome is will (naturally) depend on the assumptions you make, as is generlaly the case with these sorts of things

[Simon_Jester]

By the time you're dispersed enough to have the resources to preemptively bomb every planet in the galaxy, you're dispersed enough to be immune to being threatened by anyone not similarly dispersed.

* And of course, I must add as usual that I'm not convinced that there is a paradox at all here. I think its more a product of our own impatience with the process. We hadn't even figured out how to find planets, let alone civilizations, and here's Enriko Fermi asking why we haven't found any!

I suspect he was more curious about why they haven't found us. Bear in mind that this was during the pre-computer era; Fermi was thinking in terms of interstellar "ships" and assuming that by now, some older and more capable race would have settled our region so thoroughly that we would have plenty of evidence of their existence.

The best thing, narratively, to come from the killing star is that if you need a motive for a sci-fi villain race, you can have them believe in this premise. Assuming you want to do an exclusively evil race, which has it's own problems.

Or its government can believe this, and keep the general populace in a state of confused terror. Or, hell, it could just be the people who control the wall socket that plugs into the Dyson sphere that believe this, while ignoring everyone else in the star system.

[Admiral Valdemar]

If someone was so inclined, they would be better, as already stated, in making a Von Neumann berserker system instead. The Inhibitors in the Revelation Space series solve the Fermi paradox quite nicely, but not necessarily through deliberate xenocide as part of some sociopathic species. Instead, they served a fairly benevolent purpose and just went a bit awry after a billion or so years on the job. When you leave certain trinkets of curiosity around systems that could only have been placed or built by an intelligence and place them in such a way that only a truly spaceborne species could access them, you have a pretty good test for any species that may pose a potential threat in the future.

The problem is, you have the be the first to do this, and that series of books had a colossal galactic resource war occur leading to these guys coming out on top to implement such a plan long before humanity entered the scene. For all we know, the Milky Way was teeming with life for the most part and it just wiped itself out long ago.

[thejester]

The idea that the Fermi Paradox exists because other species have figured it out and are hiding is pretty interesting and cool, but the rest of the premise makes some enormous assumptions about alien behaviour that are really grounded in a pretty narrow view of human history and interaction (maybe I'm drawing a long bow but the fact this was published in 1995, after both the Bosnian and Rwandan genocide, seems like a pretty big coincidence). It assumes for example that a species will be the major unit of political identification and not some equivalent to the nation; and if you take that idea, the whole premise falls down. If members of nation A are fighting nation B and discover humanity in the process, why would they commit genocide when they could harness us as an asset?

[amigocabal]

Also, any civilization that doesn't learn the lesson of how to get along will likely have either blown themselves up in civilization-ending global thermonuclear war, or driven themselves into extinction due to self-induced environmental collapse ... all of this well before the point that they could seriously consider lobbing fractional-cee missiles at their neighbors.

Are there any historical examples of earthly civilizations that blew themselves up, were blown up by foreigners (or torn down with catapults and battering rams) or drove themselves to extinction due to self-induced environmental collapse because they did not "learn the lesson of how to get along"?

[Alyeska]

On another note. Is the Killing Star a good read?

[SpaceMarine93]

On another note. Is the Killing Star a good read?

The characters are a bit less developed, and it's a little dry, plus a few mistakes in the science, but it has lot of good ideas and is generally very hard as a Sci-Fi, and the story (composed of many plot threads covering multiple survivors) is flat-out terrifying. All the reviews then and there recommended it.

[Simon_Jester]

Also, any civilization that doesn't learn the lesson of how to get along will likely have either blown themselves up in civilization-ending global thermonuclear war, or driven themselves into extinction due to self-induced environmental collapse ... all of this well before the point that they could seriously consider lobbing fractional-cee missiles at their neighbors.

Are there any historical examples of earthly civilizations that blew themselves up, were blown up by foreigners (or torn down with catapults and battering rams) or drove themselves to extinction due to self-induced environmental collapse because they did not "learn the lesson of how to get along"?

Heck yes. Although "how to get along" is complicated; it doesn't just mean the capacity for peace, if also means the ability to keep track of not screwing up one's environment. Easter Island is the textbook example of this happening in micro: the Easter Islanders were doing quite well until a combination of internecine warfare and having cut down every last tree on the island caught up with them.

Meanwhile, there are a fair number of ancient civilizations that were wrecked by enemies, people reduced to barbarism, or slaughtered/enslaved until they ceased to exist as a coherent culture. Assyria comes to mind.

If the same ancient behaviors are scaled up to modern or post-modern technology, the result is extinction for the species; it becomes too easy to decide that your enemies should be exterminated, their buildings burnt to the ground, and their fields sown with salt. One missile will do the trick.

[SMJB]

There's a sweet spot for that sort of logic (which as a number of posters have pointed out is far from absolute in and of itself)--basically, the civilization has to be small enough where the new guys just breaking out of their star system are an existential threat. Basically, an empire with a few dozen stars might think like that, but one with a few million stars? Even assuming relativistic missiles are the ultimate weapon, we would stand no chance against an empire that size. We can hit, what, the two or three closest systems? Basically, for us to be a threat to them, they have to be only a few centuries ahead of us at the time of contact.

Now consider the fact that even if their home star and -planet formed at the exact same time ours did, we're talking about a time scale where a million years is a rounding error. Yeah, I don't think we're going to hit that sweet spot.

[someone_else]

So any first encounter has a 50% chance of humanity getting screwed by god-like beings basically. A fight between Cro Magnon and modern US army will seem fair in comparison.

[SMJB]

Pretty much. But the elven million years it would take a civilization on the exact opposite end of the habitable galaxy to get here at a leisurely rate is also a rounding error. Really, the question isn't "Why haven't aliens made contact with us?" so much as "Why didn't they colonize our world when we were nothing more than blue-green algae?"

[Formless]

There's a sweet spot for that sort of logic (which as a number of posters have pointed out is far from absolute in and of itself)--basically, the civilization has to be small enough where the new guys just breaking out of their star system are an existential threat. Basically, an empire with a few dozen stars might think like that, but one with a few million stars? Even assuming relativistic missiles are the ultimate weapon, we would stand no chance against an empire that size. We can hit, what, the two or three closest systems? Basically, for us to be a threat to them, they have to be only a few centuries ahead of us at the time of contact.

If you have the ability to colonize other star systems, you are already either capable of making a Dyson swarm, which makes you invulnerable to relativistic attack, or you can break the speed of light, in which case realism and the laws of physics can sit this one out.

Generally, The Killing Star and relativistic rockets are considered a HARD sf idea, not a pew pew lazors soft sci fi idea. Interstellar empires are just the opposite. Travel between stars is a massive undertaking thanks to the sheer distance involved, unless you can just say "Mr. Sulu, take us to Warp".

[SMJB]

There's a sweet spot for that sort of logic (which as a number of posters have pointed out is far from absolute in and of itself)--basically, the civilization has to be small enough where the new guys just breaking out of their star system are an existential threat. Basically, an empire with a few dozen stars might think like that, but one with a few million stars? Even assuming relativistic missiles are the ultimate weapon, we would stand no chance against an empire that size. We can hit, what, the two or three closest systems? Basically, for us to be a threat to them, they have to be only a few centuries ahead of us at the time of contact.

If you have the ability to colonize other star systems, you are already either capable of making a Dyson swarm, which makes you invulnerable to relativistic attack, or you can break the speed of light, in which case realism and the laws of physics can sit this one out.

Generally, The Killing Star and relativistic rockets are considered a HARD sf idea, not a pew pew lazors soft sci fi idea. Interstellar empires are just the opposite. Travel between stars is a massive undertaking thanks to the sheer distance involved, unless you can just say "Mr. Sulu, take us to Warp".

I am of course not talking about interstellar empires in the sense of being a unified political entity any more than I am talking about them being a literal empire with a literal emperor. I mean, come on.

[Formless]

I am of course not talking about interstellar empires in the sense of being a unified political entity any more than I am talking about them being a literal empire with a literal emperor. I mean, come on.

You're missing the point quite spectacularly. Being an "empire" or not has nothing to do with the feasibility of interstellar travel.

[Cykeisme]

Rationally, I'd actually have to support the psychotically aggressive side rather than the emotional preference to hope for peaceful contact with extraterrestials.

The way I see it, we can argue back and forth about the probability of aliens attempting to destroy us or not, but at the end of the day it's purely academic: When the cost of making a mistake (by not destroying a neighbour that turns out to be belligerent) is utter annihilation and extinction of our species, then any mistake is too expensive.

Essentially, the cost is too high to deal with probabilities.

Thing is, the cost of being wrong by hiding and trying to cautiously scope out the universe and get a sense for what it's like out there is much lower than the cost of being wrong by being a murdering asshole who suddenly discovers that he's actually a small fish in a big pond, and that his attempt to murder a slightly less advanced civilization has attracted the hostile attention of a far larger and more powerful one that he can't hope to defeat.

The only really valid argument I've seen against this is what Simon Jester suggested.. hiding, spreading out our population centers and facilities as much as possible (throughout our solar system, or even beyond) and scoping out our surroundings as best as we can.
If our species can't be "beheaded" in a single killing stroke, either by hiding our "head" or simply spreading out our civilization until we don't have any "head" to RKV, we can more safely take the cautious, peaceful approach that I'd prefer.. scouting out and hopefully making diplomatic contact with interstellar neighbours without it immediately coming to blows.

In The Killing Star, humanity neither took measures to make our civilization more resilient, nor (as Pellegrino suggests) did they RKV the crap out of any possible life out there. Either measure would have allowed our civilization to survive (in some capacity, at least).
In reality, we can't afford to make the same mistake.