Haven't The Gear

Many years ago I was sent to England on business. A driver picked me up at Heathrow to drive me to my place of work in Basingstoke. Nice car, too - a big comfy Mercedes so shiny and black I could practically hear Darth Vader's heavy breathing every time I glanced at it. But some sort of irritating flying insect had gone up the driver's nose and he had an axe to grind. This was not long after Operation Desert Storm in the early 1990s, and my British driver felt the need to tell me what he thought of Americans in general, and the US Air Force in specific. The American military was a bunch of amateurs, he claimed, and the Royal Air Force had had to carry the bulk of the burden in Desert Storm because "you Yanks haven't the gear." According to him, the British had flown most of the sorties in Desert Storm because US aircraft and weapons were inferior, US pilots were untrained rabble, American junk was shot out of the sky as soon as it appeared, and only the British could get the job done.

At the time I'd already helped myself to a series of reports submitted to the Office of Management and Budget, which included among other things a very detailed inventory of "select aircraft types" that flew missions in Desert Storm. Certain aircraft were not listed. The AC-130 was not in the report, for example, because its mission profile didn't fit the "sortie" model that the report was based on. F-15C Eagles were not included, as they flew air superiority missions and had no ground attack mission programming (though a separate section on the report on F-15C Eagle air-to-air kills in USAF and Saudi hands made fascinating reading). Other aircraft, such as United Arab Emirates Mirage IIIs or Kuwaiti A-4s, were not in the report because they were felt to be statistically insignificant. And some aircraft were excluded for reasons I simply can't fathom, such as F-4G Wild Weasels, B-52 Stratofortresses, A-7 Corsairs, USMC AV-8 Harriers, and F-111Es (the report only included F-111Fs).

So the data aren't entirely complete, but the report does paint a pretty clear picture, and several conclusions could be drawn from it. The most obvious one is that the vast majority of programmed strike missions in Desert Storm were flown by US aircraft, and specifically USAF aircraft. In fact, the breakdown looks a bit like this:

Aircraft Percentage of Strikes

F-117 Stealth Fighter 5.03%

A-6E Intruder: 7.36%

A-10 Thunderbolt: 24.31%

F-111F: 7.88%

F-15E Strike Eagle: 5.98%

F-16C Falcon: 32.92%

F-18 Hornet: 12.81%

Tornado GR.1: 3.71%

Two USAF types, the A-10 and the F-16, flew over half of all programmed strike missions in Desert Storm, and the total USAF contribution amounted to about 76% of all missions, and that doesn't include F-111Es, B-52s, or F-4Gs. Not bad for people who "haven't the gear."

Another interesting part of the report listed Coalition air losses. Here are the tabulated air losses from Desert Storm:

Aircraft Number Lost

F-117: 0

F-111F: 0

F-15E: 2

A-6E: 3

A-10: 5

OA-10: 2

F-16: 3

F-18: 3

B-52: 0

Tornado GR.1: 9

F-4G: 1

F-14 Tomcat: 1

EF-111A "Sparkvark": 1

OV-10 Bronco: 2

AV-8B Harrier: 5

AC-130 Spectre: 1

F-5E Tiger II: 1

A-4 Skyhawk: 1

The striking thing here is the Tornado GR.1, which suffered by far the highest absolute and percentage loss rate of any airplane in Desert Storm. The Tornado GR.1 loss rate per mission was twenty-six times higher than the F-16s, which isn't very good for an aircraft which, presumably, "has the gear". (There are reasons why the Tornado's loss rate was so high. The Tornado's low-altitude, high-speed mission profile is very demanding even in peacetime, and I can't imagine the balls of the British and Saudi pilots who flew those missions at night, with tracers and missiles coming up, in hostile territory. But it is interesting to note that once the RAF abandoned these low-altitude missions and adopted the USAF model of dropping PGMs from medium altitude, using Buccaneers as marker aircraft, Tornado losses dropped to about what one would expect - basically zero, in other words.)

Someone Famous once said that there are lies, damned lies, and statistics, and the accuracy of my analysis can be no more accurate than the data that was in the reports submitted to the OMB. And institutions (such as the USAF, the RAF, and even NASA) have on occasion been known to spin statistics in their favor. But it's hard to fake things like the numbers of aircraft committed, the numbers of missions flown, and the numbers of aircraft shot down. Where the fudging may have taken place is in the part of the report that listed "fully successful" missions as opposed to "not fully successful" missions, and I won't speculate on that data. It is altogether too easy for analysts to adjust the success criteria to make whatever point they want to make, and in any event, it's hard to tell in the real world if a given strike has been fully successful or not. When you attack a single tank with a GBU-10, success is pretty easy to determine. But when you attack the Baghdad Nuclear Research Center with a strike package of 60+ assorted aircraft, how exactly do you determine whether you were "fully successful" or not?

I knew all this, but I didn't argue with the driver. Mistaking my silence for agreement, he seemed very pleased with himself, as though he'd scored some sort of moral victory over those awful, amateurish Colonials, and restored the Crown to its rightful stature. But I've rarely been so happy to get out of a car as I was that day, and I drew considerable comfort from the fact that I'd never see him again.

But not because of his obvious and fairly impassioned anti-American bias. He has the perfect right to think whatever he wants about Americans, or Germans, or Brazilians, or about the Scots, for that matter. I really couldn't have cared less what he thought of America or Americans. I disliked him because I am readily irked by ignorant, uninformed people who won't keep their ignorant, uninformed cake-holes shut. I don't mind ignorance. And I don't mind obstreperousness. But obstreperous ignorance really wears me out. So if you're going to give me a 45 minute lecture on something, please endeavor to know about it than I do. There are a great many subjects that I know nothing about. Public education, psychology, gene splicing, TCP/IP protocols, cell phone apps, Russian politics, child-rearing, Paris Hilton, the stock market, monetary policy, Hinduism, class warfare in Brazil, narco-trafficking, HDTV, fashion, book publishing, tensor calculus and a hundred others. So please lecture me on something I don't know about, so it's a win-win all the way around.

The car driver's impression of the US military isn't exactly unique. There's a widespread bias in books written by British authors against the US military. Some of their criticisms are certainly valid, such as the observation that the US Army worried so much about the old threat (the Soviet Group of Forces in Germany) that it was poorly trained and poorly equipped to deal with the new threat (Osama bin Laden on horseback escaping from Tora Bora). British critics who pointed out that the US Army's tendency to relentlessly escalate the application of firepower in any given situation was counterproductive in an insurgency were right - there were even Americans who said that, chiefly US Marine Corps counterinsurgency experts, who seemed to be the only people in the US military who did any serious thinking about asymmetrical warfare at all.

Mostly the European bias against the US military is expressed in glossy photograph-laden popular books about weapons, especially tanks and airplanes. There's often a sort of sports mentality to the thing, where Some British Guy asserts that the Tornado is way better than any stinking American airplane simply because it's British. And if you read enough of these books, you find yourself inhabiting a world where European and especially British weapons are always superior because Americans are bumpkins fascinated with gadgets. The Eurofighter Typhoon is way better than the F-16. The Tornado is way better than the F-15E. The Rafale is way better than the F-18. The Vulcan was way better than the B-52. And certain notorious program failures, like the TSR.2 and the Avro Arrow, always seem to end up being my fault in some way (as an American, I am apparently an accessory after the fact to whatever nefarious American schemes that led to the cancellation of the TRS.2 or the Arrow or whatever).

To be fair, there are plenty of American writers who do the same thing, only in reverse. The F-16 becomes the most amazing fighter ever built simply because it wears stars-and-bars instead of roundels, and the whole thing turns into slightly goofy boosterism - my football team is better than your football team because everyone knows that red jerseys are better than green jerseys! My football team is better than your football team because you live in a warm city and the climate makes people soft and flaccid, while my cold and demanding climate makes linemen tough and mean! My football team is better than your football team because... Well, because I've attached my ego to my football team and I demand that it's better!

This doesn't bother me. I generally hew to the Trevor Dupuy school of thought anyway, which is that in the end, the exact operational parameters of any given weapon aren't nearly as important as the uses to which you put it - that leadership, logistics, organization, surprise, training, and even numbers are in the end considerably more important than whether this airplane is a bit faster than that one, or whether this airplane can turn at 9.5 gees and that one can only turn at 8.5 gees. One wouldn't expect a Sopwith Camel to prevail against a Focke-Wulf Fw 190 in air combat too many times, but as long as the airplanes are reasonably comparable - a Spitfire V against an Fw 190 - the "paper" advantages of one airplane over the other are largely swamped by other, often intangible factors (maybe, on the day in question, Fritz had a hangover and never saw Nigel in his Spitfire until it was too late).

So I was driving home from work the other day, listening to the BBC news on NPR, and some NATO "defence" spokesman was pleading for help from - gasp - the United States Air Force. Apparently, according to this spokesman, NATO lacks aircraft with "precision ground attack capability." But wait a minute, haven't you guys been cudgeling my brain for the last ten years on the superiority of the Tornado, and the even more sheer superiority of the Typhoon? If they're so good (and they are good, I don't doubt that) why does NATO need "precision ground attack capability" from the US Air Force? Are you admitting, in your roundabout fashion, that the US Air Force possesses capabilities that your air forces don't?

Of course it does.

What this NATO spokesman was asking for were two USAF aircraft in particular, the A-10 Thunderbolt and the AC-130. Yes, I know most people call A-10s "Warthogs", but for some reason I just don't feel entitled to use insider jargon in such matters. My friend may have served on the "Bonnie Dick", but to me, it was the USS Bonhomme Richard. My uncle may have worked on "Aardvarks", but to me, they're F-111s. A distant, distant uncle may have flown a "Gustav", but to me it's an Me 109G.

But whatever I call it, it seems clear to me that NATO is asking for A-10s and AC-130s, aircraft that are capable of attacking ground targets in a fairly heavy-duty way. As far as I know, no other air force has aircraft like the A-10 or the AC-130, the nearest analog to the former being the Russian Su-25, and nobody else has anything like the AC-130.

They don't have a single good thing to say about the US Air Force, but when it turns out that they can't destroy elderly Libyan T-55 tanks that are almost completely unprotected by battlefield air defense systems, they plead for A-10s and AC-130s.

It must gall my British car driver to no end to realize that, in the end, "they haven't the gear."

Writer's Block

Boy have I have writer's block lately. I'm sure this is a cause for national alarm. "He had writer's block! Quick, someone send him a cup of tea or something to get him unstuck!" Most people probably think writer's block is a made-up condition, a chic affectation of some self-described intellectual elite. But it's real, and it sucks.

It isn't that I don't have ideas or things that I want to write about. I just can't seem to articulate anything. It's like knowing you want to build a cabinet, but every time you plunk down a piece of wood on the table saw, it comes out ragged or crooked or flies out of the saw with such force is goes through the wall and into the neighbor's house. After a while you get gun-shy and reject every idea. "A novel about an imprisoned cannibal serial killer who helps an FBI agent solve a series of gruesome murders? That's STUPID. Nobody will buy that."

Back in my college days I found calculus a somewhat difficult subject. I still do, and recognize my relative lack of facility with higher math as a kind of character flaw. Sometimes during tests I'd erase my work so many times I'd erode holes through the paper, and afterwards when I stood up a half a pound of overheated eraser crumbs would fall off my lap onto the floor. That's kind of like what having writer's block is like - I produce a lot of eraser crumbs and I backspace over things so many times the phosphors fall off my computer screen, but I never seem to actually write anything.

To an extent, writer's block in an amateur writer is kind of silly. It's like telling someone "My doctor has advised me not to attempt Mount Everest" while you're standing in Iowa. It may be true, but so what? But since I am now by my own definition anyway a published author, it is now a professional handicap, like someone suffering from Tourette's Syndrome trying to make a living as a professional poker player ("Son of a bitch! Three of a kind!") I'm not MUCH of an author - one writing job for an extremely niche magazine - but hey, one has to start somewhere.

Usually I have the opposite problem - namely, writing WAY more than was necessary or wise. I'm sure when I turned in my magazine job, the editors had to take a hedge clipper to it. "We asked for 1500 words and we got this! Hand me the chain saw!" It isn't easy being edited, especially when you tend to run long by nature, but it probably isn't easy being an editor either, asking for 1500 words about the Chinese invasion of Tibet and getting something on the scale of Ulysses S. Grant's memoirs. I have to imagine that editors must sometimes clap their hands to their foreheads and sigh "How many bags of M&Ms did he have to eat while he wrote this opus?"

I'm always amused when people tell me how they had to squeeze in the margins and enlarge the font to get their scrawny papers up to five pages. I was always having to move the margins out and use fonts like Flyspeck-3 to get them down to five pages. I wrote a paper for some sociology class once whose mere bibliography was longer than the complete papers of most of the other students. Another time I was placidly typing away at a novel and realized that I was up to 1,150 pages and I still had no idea how to end the thing! I still don't. A long time ago I was writing a novel on my old Commodore 64 and hit the limits of how big the document in the word processor could be. Not one character more would fit. I felt a bit like a chastened Christopher Columbus sailing off the edge of the word crying "Crap! I thought the edge of the world was just a metaphor!" Another time I was writing a paper about the early days of NATO, especially the decision to allow West Germany to rearm, and was suddenly struck by the fact that I was writing a section on the Franco-Prussian War of 1870! Now THAT'S a digression. (One might profitably surmise that writing outlines isn't one of my strengths either. But I'm pretty good at writing outlines. I just suck at sticking to them.)

Normally I have two weaknesses as a writer. The first is that I can be unbelievably prolix. The second is that I have trouble finishing anything. The two are related, but distinct. In a nutshell, I'm bad at writing the way Stephen King advises. That is, to write the dang thing down at least once with no attempt to edit, self-censor, embellish or otherwise meddle. Write it once, finish it, and then put it away for a while to steep. Me, I get halfway through, have a better idea, back up, start over, become disillusioned with the better idea, undo everything and revert to the original, make some more progress, then decide that the better idea was better after all... "No! Circus clowns! That's it! It's all circus clowns and it takes place in... Paraguay! Yes! No! Yes!" It starts out being a horror novel, so why have I written thirty pages on how rock crushers at gravel pits work?

It's so demoralizing.

The result is a hacked-up mass of scar tissue that makes Joseph Conrad seem breezy and concise. And then there's the fact that they never actually end; I just run out of interest or ideas or, sometimes, memory in my computer.

But these days I'm really stuck, and it's frustrating. The best approach is to not worry about it. It's like trying to remember Ethel Merman's name - as soon as you stop trying to remember it, you'll remember it. But it takes longer. To get rid of writer's block, I have to stop writing for a week or two, and that's bad. Writing is (for me, anyway) a bit like taking out the trash: if I don't do it on a fairly regular basis, things kind of pile up and start to smell. So not writing for any length time amounts to dropping a tuna fish sandwich in the kitchen trash can and pretending it isn't there for a week or two, olfactory clues to the contrary.

So that unpleasant smell you're picking up right now? That's just my tuna fish sandwich.

Martian or Lunatic?

I used to be an unconditional proponent of manned spaceflight. Manned spaceflight was good by definition, and I didn't need no steenking arguments about jobs, spin-offs, or anything else to justify it. And that's still generally true. If the choice is between manned spaceflight with no purpose, or no manned spaceflight at all, I'll take manned spaceflight for a thousand, Alex.

But I'm not as naive as I used to be, and while I'm still a strong proponent (or exponent?) of manned spaceflight, I'm reaching an age and level of maturity where I'd like to see results. Manned spaceflight, yes. But preferably, manned spaceflight for a reason, and not just so we can say we have some government employees floating around up there.

Let's cut the mustard (or the cheese) right up front: people in space appear to generate very little in the way of fundamental science. When you name some of the most fruitful space explorations in terms of raw scientific output, they're always unmanned: Hubble Space Telescope, Galileo, SOHO, Voyagers 1 and 2, Viking - the list is endless. What great hauls of scientific data has manned spaceflight brought back? Umm....

The point of people in space isn't to do Big Science. People actually get in the way of that. Ever wonder why there isn't a big telescope mounted on the ISS? Because the vibration of all those people moving around, and all those fans and pumps that keep the people alive, makes for truly miserable seeing through a telescope.

Well then, what's the use of sending people into space at all? If it's easier and cheaper to launch robotic probes, and if the scientific haul is better anyway, why send people up there at all? Well, basically, to study how people live in space. The goal of putting people in space should be to eventually develop the ability to send them somewhere and establish, if not an actual colony, then at least a semi-permanently manned facility. So when we send people to the ISS now, it should be with the goal of developing the capability for manned interplanetary spaceflight.

NASA seems bad at articulating this sort of strategy. They present all sorts of arguments in favor of the ISS, but never the most important one. They talk about the science, the economic benefits, the technological spin-offs, but they never seem to come out and say "We want to learn how to live and work in space so we can go to Mars." I'm not naive and I know why they don't - going to Mars sounds like science fiction, and very expensive science fiction at that, and if the average lawmaker in Washington suspected that NASA was having Martian dreams, they'd probably preemptively de-fund the whole thing. In the same way that von Braun had to build vengeance weapons for Hitler to pay for his private dreams of colonizing space, NASA has to do what Congress will allow it to do so it can have its private dreams of colonizing space too. And as Carl Sagan once said, if Teflon is your main justification for the Apollo program, wouldn't it have been cheaper to just develop Teflon in the first place and skip that whole moon business?

The point of putting people into space is to send them somewhere so they can live. Ultimately, so that if something dreadful happens (asteroid impact, nuclear war, pandemic) and civilization on Earth crumbles, there'll be other human civilizations out there that won't go down the drain with the mother planet. That is the basic reason for going - so that if the worst happens, there'll still be people out there somewhere who remember Beethoven.

But where should we go? The moon seems like an obvious candidate - we've already been there, and it's close at hand. But I think building a permanent presence on the moon would amount to a long and very costly sideshow.

Moon proponents point out that eons of exposure has filled the crust of the moon with a rare isotope of helium, helium-3, and that it might be commercially lucrative to mine the lunar regolith for helium-3 and ship it to Earth, where it could be used in fusion reactors to provide essentially free energy. And that argument might make sense if we actually had fusion reactors that could use helium-3, but we don't, and probably won't for another hundred years pending some exotic breakthrough in magnetohydrodynamics.

I think Mars is by far the most logical candidate for future human colonization, much more so than the moon or the asteroids.

Mars has water. Lots of water. And water is practically the sine qua non of a space colony. And Martian water is probably going to be a lot easier to get at than whatever scant amounts the moon can offer.

Mars has an atmosphere, which means you can do all sorts of things with heat shields and parachutes to lose velocity that you can't do on the moon. Aerobraking and parachute-retarded entry have engineering challenges of their own, but as recent Mars probes have shown, once you figure out how to do it, you can use the atmosphere as a powerful brake and save enormous quantities of rocket fuel.

Mars has free carbon dioxide in its atmosphere, free for the taking. Carbon dioxide isn't too useful to humans in its native state, but it can be used as feedstock for chemical reactions that produce things that are useful to humans.

The Martian atmosphere provides pretty good protection from meteoroids, so you can think about building large inflatable structures without having to worry too much about them being deflating by any passing grain of dust. Large impacts can still deflate your domed city, but the Martian atmosphere essentially removes small objects as potential threats.

The Martian atmosphere provides at least some radiation shielding. Mars has no ozone layer, so the surface is exposed to full-bore ultraviolet radiation. And Mars has no magnetic field, so the solar wind isn't deflected as it is around Earth. But random collisions with the Martian atmosphere would attenuate at least some of the radiation threats. You'd probably still need to bunker in and sleep underground to protect yourself from the solar wind, but you'd have to do that on the moon anyway.

The Martian atmosphere offers advantages in cooling. On the moon, the only means of cooling anything is radiation. But on Mars, heat exchangers or radiators become possibilities, so the power density of your power generation systems can presumably be increased because of the more competent cooling schemes available. There wouldn't be a lot of cooling by convection or direct transmission, but some is a lot better than none.

The Martian day is pretty close to an Earth day, which would seem to have advantages in terms of adaptation. A lunar "day" is about two weeks long, which would take some getting used to, but a Martian day is about twenty-four-and-a-half hours.

The Martian atmosphere moderates temperatures. On the moon, temperatures vary wildly as objects pass through shadow and sunlight. Temperature swings of hundreds of degrees exist, and engineering things so that they aren't damaged, overwhelmed or even prematurely fatigued by wild temperature excursions is tricky. But on Mars, it's mostly just cold. There are temperature extremes, and it still gets plenty cold, but the atmosphere limits the scale of the swings so your engineering challenge is somewhat less daunting than it would be on the moon.

Mars isn't perfect. The atmosphere is extremely thin and some sort of pressure suit would still be required. It isn't a vacuum and it wouldn't kill you as quickly as a vacuum, but it would still kill you, and in a matter of minutes rather than hours. The topsoil on Mars isn't very hospitable either. The incessant bombardment by ultraviolet radiation (which is bad in and of itself) creates weird peroxides and superoxides in the Martian soil, and it isn't entirely clear to me if they would present a health risk if you tracked in a bunch of that junk on your boots. And since Mars has no magnetic field, you can't rely on compasses to tell you which way to go. But these caveats are all true of the moon as well, and the moon doesn't appear to offer any compensating advantages.

The moon has, as near as I can figure, only two real advantages. The first is that it has a low escape velocity and no atmosphere at all, so it isn't entirely unrealistic to imagine that one could launch cargoes from the moon using some kind of mass driver or rail setup. The other is that the far side of the moon is the only spot in the solar system that is permanently shielded from Earth's endless electromagnetic radiation, and it would be a good spot to build big radio telescopes.

But past that? I'd rather be a Martian than a Lunatic.

Fermi Paradox

I enjoy thinking about the Fermi Paradox.

The Fermi Paradox, if you haven't heard of it, basically amounts to the question "Where the hell is everyone?" If the universe is as old as we think it is, and if it's as large as we think it is, and if it's as full of water, organic molecules, and temperate planets as we think it is, how come the universe isn't teeming with intelligent life? How come all our SETI screensavers aren't finding alien radio signals all the time? Why the hell is the universe so silent?

Who knows why. But it's fun to posit possible answers to the Fermi Paradox, mostly because it's so much like writing science fiction. There's no evidence one way or the other, and for now there isn't even hope of find any evidence, so we can imagine whatever we want, in effect projecting our particular outlooks on the universe at large.

Some answers are religious in nature - that is, that God made man in His image on one planet and one planet alone, and the rest of the universe is nothing but a fairly showy backdrop for our terrestrial drama. Some answers have a deep-rooted pessimism that basically argue that the coefficients we plug into the Drake Equation aren't just wrong, they're wildly wrong, many orders of magnitude wrong, leading to so-called "lonely Earth" scenarios.

But the best ones sound like the plots of science fiction novels, or vice versa.

Such as the theory that the aliens are already here, but such is their technological sophistication and their discretion that they only reveal themselves to selected individuals, often in rural settings. Why they'll visit the guy that runs the body shop and not the President is a question I leave to the specialists.

Such as the theory that some alien race somewhere along the line developed nanotechnology, but didn't put enough safeguards in place. Their nanoassemblers got loose, and now the biospheres of most of the planets in the universe consist of barren rock and a grey goo of trillions of nanoassemblers.

Such as the theory that some alien race, on the losing side of some terrible war, built a doomsday weapon of some sort that got out of control, and this weapon now cruises the universe, still faithful to its original programming of finding and exterminating life where it finds it (insert here any number of science fiction stories, everything from Star Trek to Fred Saberhagen's Berzerkers). Who knows, maybe even as you read this, this terrible doomsday machine has detected the ghostly signals of Three's Company re-runs and is already on its way to Earth.

Or maybe the "default egghead position" is wrong, and that advanced alien civilizations are not necessarily peaceful, benevolent, or even indifferent; maybe they're openly and avowedly hostile and think nothing of wiping out, enslaving, or even eating lesser civilizations, such as ours.

Or maybe the universe is populated by some incredibly powerful alien civilization, a civilization so advanced that it doesn't even recognize us as being intelligent, and maybe this alien race dispassionately exterminates young civilizations where it finds them, the same way we spray new ant colonies where we find them.

Or maybe some group of wise alien civilizations had a big meeting and decided that we were currently too brutal, too primitive, too warlike to make contact with just yet, so they've put us in a kind of galactic play-pen until we grow up a little.

Or maybe life is common, but intelligent life is not so common because it is the habit of technological civilizations to develop the means of mass destruction (that is, nuclear weapons) before they develop the wisdom to refrain from using them.

Or maybe it is the habit of young technological civilizations to exterminate themselves through ever more destructive wars, or to engineer their own demises through foolish genetic experiments, ecological mismanagement, or technological hijinks like the famous Tralfamadorian spaceship propulsion system accident that Kurt Vonnegut wrote about.

Or maybe it's more sociological than that. Maybe it is the habit of the citizens of technological civilizations to get so hooked on materialism and entertainment they forget that civilization doesn't exist to exalt the ego of the individual, but to ensure its own survival and success, and thus yet another civilization slips into what Arthur C. Clarke called "the dream of the lotus-eaters".

Or maybe the universe just isn't a very good place to live. Gamma ray bursts are rare, but maybe they happen just often enough that most of the universe at any given time is either being sterilized by a gamma ray burst, or recovering from being sterilized by one.

Or maybe every civilization eventually reaches the point where it can build particle accelerators powerful enough to create strange forms of "exotic matter" like magnetic monopoles and strangelets that go on to consume their planets right out from under them.

Here's my take. Maybe in every technological civilization there exist budget-cutters who kill their space programs so that when a big planet-killing asteroid comes along, and one most assuredly will, they don't have any kind of efficient nuclear propulsion systems that would allow them to deflect said planet-killing asteroid.

Hmm.