Five Obstacles to a Realistic Interstellar Empire

From Star Wars’ aptly named Galactic Empire to Star Trek’s United Federation of Planets, interstellar civilizations are a pillar of science fiction. Somehow, humanity breaks the light-speed barrier and reaches the stars. Maybe we’ll meet some aliens along the way, maybe not. Either way, our civilization is destined to spread through the Orion Arm, across the Milky Way, and perhaps even further.

But has anyone thought through what an interstellar nation, empire or otherwise, would entail? Even assuming you had the necessary technology to make one, would it really turn out the way science fiction promises? Several obstacles stand in the way.

1. Administration Would Be Unmanageable

The larger an organization, the more difficult it is to run. Top leadership can’t manage everything, so they delegate authority to lieutenants, who in turn delegate further. Every level adds another delay in communication as orders and directives are passed from person to person. Every person in the chain of command adds another chance for someone to make a mistake, and that’s assuming everyone is playing by the rules. The larger an organization, the more chances people have to hide corruption. Even small things, like a security guard taking $20 to bump someone up in line, will add up eventually and hurt efficiency.

Consider the European Union. As an organization, the EU has its pros and cons, but even the most ardent Euro-supporter won’t deny how unbelievably complicated the whole thing is. With 28 member states, many of which don’t even share a language, anything important takes a long time to resolve. Even something as simple as rescuing shipwrecked refugees is a huge endeavor. Now consider that the EU countries represent most of one small continent on one planet.

Scale that up to an entire planet, then dozens of planets, if not hundreds, and you see the problem. Any such entity would have to juggle a myriad of different, possibly competing interests. At first, this might not seem so bad. The residents of Alpha Centauri III are convinced the space government should invest more in asteroid-mining subsidies, but Epsilon Indi IV is strongly opposed. Solve the disagreement, and you’re golden, right? Not so fast. Can you imagine anyone talking about the people of Earth as a single, united group? When have the people of Earth agreed on anything? Unless it is recently settled, every other planet in your space government will have the same problem.

This is all assuming your setting even has the technology to sustain regular contact between scattered worlds. Empires survive on communication; otherwise they’re impossible to coordinate. There’s a reason so many empires of the past are known for their long lasting roads.

How to Solve it

First, make sure your setting has instantaneous, or near instantaneous, communication. Even if it’s not available to the general public, leaders should be able to speak to each other without delay. Once that’s done, you might introduce a special ability that allows the leaders of your empire to keep everything running despite all the layers of bureaucracy. If it’s a democracy,* consider a neural implant that allows representatives to get through endless debates at lightning speed. That would be excellent fodder for a story, as well. Your character wants to join parliament to serve their world but isn’t sure they can bring themselves to give up full autonomy of their thoughts.

Another option is to have one center of power in your empire. The homeworld or seat of conquest dictates the actions of everyone else. That way it doesn’t matter what people on other planets think. This works best for young empires, as it’s not a very stable form of government, but it can easily work long enough for your story.

2. Accommodations Would Be Complicated

This is actually the line for the space bathroom. This is actually the line for the space bathroom.

Imagine that, in addition to humans, Earth was home to a species of sapient ostriches. They’d walk on two legs and use opposable thumbs, but that’s where the similarities to humanity ends. Like their mundane cousins, these ostrichians lay eggs, have feathers, and easily grow up to nine feet tall.

Now imagine designing facilities for both humans and ostrichians. Hallways would need to be taller, for one thing. Since ostrichians have completely different dietary needs, feeding everyone would get complicated, too. What about disease? Are there any illnesses one species carries that can wreak havoc on the other? Let’s not even get started on toilet facilities.

That’s the reality for any interstellar civilization. In fact, the ostrichians are a minor example. They’re only one species, and at least they evolved on the same planet as humans. If your story is set in a crowded galaxy, there could be dozens or hundreds of alien species to contend with. Will they breath the same air as humans? Are they even made of the same type of matter? Unless you go the Star Trek route, where every alien is actually a human in forehead makeup, the answer is likely no. This is assuming humans and aliens are enough alike to communicate.

But perhaps you can avoid this obstacle by only populating your world with humans. That will help, but it won’t solve the problem. Once humans have lived in a new environment long enough, they’ll start to adapt, intentionally or not. Humans living on low-gravity worlds will find Earth gravity painful, perhaps even deadly. Humans who engineer themselves for hotter worlds may find normal Earth temperatures frigid.

How to Solve It

Instead of sweeping the issue of differing biology under the rug, embrace it. In The Expanse, the story centers around the diverse needs of humans from different parts of the solar system. Belters chafe under Terran gravity, while Earthers complain about the artificial lighting everyone else in the system is accustomed to.

You don’t have to go that far; simply acknowledging the issue is often enough. When the captain of your starship calls a senior officers’ meeting, include someone from the department of interspecies relations. Such an officer would make a great main character for a story about tension-fraught first contact.

You could also sidestep the issue with a universe like Babel 17, where alien civilizations exist but are too different from humans for meaningful interactions.

3. Warfare Would Be Impractical

LennonWallImagine Lennon Wall by Adam Zivner used under CC BY-SA 3.0

Most space-opera stories include some interstellar war or at least the threat of it, which makes sense. War is a great source of conflict and an exciting way for authors to show off their cool scifi tech. It’s unfortunate, then, that interstellar civilizations have little reason to fight one another.

First, there’s the immediate practicality of fighting a space battle. Short version: they’re not very exciting. Instead of X-Wings and TIE fighters duking it out, we’d get robot ships firing at each other from so far away that the enemy is little more than a dot on a screen.

Taking over a planet through military invasion, another staple of the genre, would be incredibly difficult. The logistics alone are staggering. Just invading the six beaches at Normandy took more than 150,000 troops. Scaling that up to an entire planet would require transporting millions, possibly billions, of soldiers across space. Then factor in how destructive science-fiction weapons can be, and you have a situation where invaders would have to devote massive amounts of resources to an attack that’s likely to destroy the very target they hoped to capture.

More pressing than the how, though, is the why. What reason would interstellar civilizations have for going to war with one another? At their heart, most wars are fought because one or more groups believe they can gain something material from the fighting. But what is there to gain in interstellar war? It’s unlikely to be resources. Even in settings with lots of inhabited planets, there are bound to be even more uninhabited ones. Almost any raw material we might need can be found in abundance just within our own solar system. Anyone with faster-than-light (FTL) capabilities could easily harvest whatever they need without having to fight for it.

What about food or livable real estate? You can’t find those on the barren rock of Mars. Surely that would be worth fighting over. Not really, because any species that can cross interstellar distances has already mastered living in space. That means they can create whatever food or breathables they need on their own. Why go to all the trouble of fighting another space nation over something you can easily make yourself?

How to Solve It

An easy option is to borrow from the Culture series. In those books, war is no longer a necessity but something a handful of species engage in out of habit. It doesn’t gain them anything, but they do it because that’s how they’ve always done things. In this type of setting, war is a tragic farce.* The only heroic acts to be had are in service of ending a pointless conflict.

Another option is to fudge your setting’s technology so that living in space long term simply isn’t viable. Maybe they never solved the problem of bone marrow loss or figured out how to protect people from long-term exposure to cosmic rays. In either scenario, it’s still possible to cross the vast distances of space on a good FTL drive, but actually living in space isn’t an option. At that point, invading another inhabited planet to set up a colony might seem like a good idea.

4. Trade Would Be Unnecessary

Sadly, this is the fate of our favorite YT-1300 Freighter. Sadly, this is the fate of our favorite YT-1300 Freighter. Old Carissa by Misserion used under CC BY 2.0

Trade binds nations, or even groups of nations, together. Without strong economic ties, there’s little reason to remain part of a large group.* The modern world is awash in trade, so it’s only natural to assume that any interstellar empire worth the name would be as well. Unfortunately, this might not be the case.

Trade is all about efficiency. If the UK produces tea for $100 a pound, and Canada produces the same tea for $150 a pound, it makes sense for Canada to import tea from the UK. Things get more complicated when you consider the cost of transportation. If it costs $75 dollars per pound to ship tea across the Atlantic, then it no longer makes sense for Canada to import from the UK.

Now, consider the cost of shipping goods across interstellar distances. That’ll add a lot of overhead. Even in really high-tech settings, it’s difficult to imagine spaceships cheap enough to make interstellar trade viable. Much easier to produce whatever a planet needs locally. Raw materials are unlikely to be profitable either, considering the vast stores that exist within just the Sol system.* Using that up would require a scale of technology most authors aren’t interested in.

Of course, there is another kind of trade. Sometimes, people will trade for something because they are incapable of making it themselves. For a long time, if you wanted porcelain of decent quality, you needed to trade with China.* However, in the modern age and beyond, that kind of monopoly is unlikely to last. Reverse engineering is much easier than it used to be.

How to Solve It

One option is to create new resources and then make them rare. While sending freighters across the Milky Way to pick up a load of iron ingots would be a huge waste, the same trip for cheap antimatter might be worth it. If only a handful of planets have access to the exotic matter that makes FTL possible, that would do a lot to facilitate trade.

You might also embrace an economy of scale. Trade gets cheaper the more you can transport per trip. Massive super-freighters, some the size of small moons, would do a lot to bring the shipping and handling fees down. This might even lead to entire planets with economies specialized in creating a single type of good for export.

Finally, you could introduce a strong reason for not duplicating off-world technology. Aliens might come to Earth with wondrous devices to trade, and their main condition would be that no one ever attempt to reverse engineer the new ET-Phone. Terrified of offending their new benefactors, the Earth government cracks down hard on anyone trying to pry open the alien tech to see how it works.

Sadly, none of these scenarios make it practical for Malcolm Reynolds to transport a herd of cattle aboard Serenity. We’ll just have to suspend our disbelief for that one.

5. Energy Production Would Outmode All Conflict

800px-Preamplifier_at_the_National_Ignition_Facility Preamplifier at the National Ignition Facility by Lawrence Livermore National Laboratory used under CC BY-SA 3.0

It’s amazing how many of our world’s problems come back to energy. For example, we have technology to remove salt from seawater or even condense water out of the air. But we still have water shortages, because both those technologies are energy intensive, and our current methods for generating energy are limited. Fossil fuels give off greenhouse gasses. Nuclear fission can be dangerous, and it creates radioactive waste that we have no good way to store. Solar power has a lot of potential, but as of this writing, it isn’t efficient enough to fill all our needs.

Faster-than-light travel, if it’s possible at all, will require vast amounts of energy. Physicists still debate exactly how much, but it’s a very high number. Perhaps a mind-bogglingly high number.

Any interstellar civilization that has already cracked the problem of FTL travel means they are capable of producing energy far beyond anything on Earth. How they do it isn’t really that important: Nuclear fusion, building a Dyson Sphere around the sun, harvesting Hawking radiation from a black hole, or a host of other options, any of it can work in your setting. The important thing is what else people would do with all that energy.

Even without Star Trek’s replicator, production capability would go through the roof. Not just synthetic production, either. Food takes energy to grow, but energy isn’t a problem any longer. Unlimited nitrogen fixing and fusion-powered grow lamps would vastly improve world food production. Meanwhile, the cost of making luxury goods would plummet. Trade and warfare become things of the past, and most meaningful conflict would cease to be. That’s great for anyone living in such a setting but not the writer trying to tell a story.

How to Solve It

Spoiler: Book three of The Expanse.

The key is to somehow lower the threshold of energy required for FTL travel. Perhaps in the future, an incredibly brilliant physicist discovers a trick that allows for hopping across lightyears without all the mass-energy expenditure of today’s theories. That allows for spaceships to zip between your worlds without creating the technology that would solve all their problems.

The Expanse features an interesting solution. In this series, humans haven’t figured out FTL travel, but they’ve stumbled onto an ancient system of warp gates left behind by a much more advanced civilization.* This allows the characters to explore new worlds then come back to a solar system that’s still plagued by shortages and conflicts any modern human would recognize.

Civilization is a complicated thing, interstellar or not, and building a convincing one will always be a challenge. Fortunately, these obstacles need not stop your story in its tracks. Instead, they can take your story in a new direction, turning it into something the audience has never seen before. That’s exactly what science fiction strives for.

P.S. I just published my first game. In it, the PCs have to figure out who they are, solve a supernatural mystery, and avoid their doooooom. Get it here.

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  1. Jehovazilla

    A lot of these can be gotten around by power imbalances. Using historical colonialism, for instance, makes long range governance more possible (albeit chaotic). It also helps with the trade problem, since colonies probably wouldn’t be as self-sustaining as a fully developed world.

    This is furhter helped if most worlds aren’t Earthlike, and terroforming is hard/impossible, which would allowed power to flow naturally to the more habitable worls.

    In the setting I’ve been playing with, I’m also using the “ancient FTL” trope, to get around energy problems, or at least a variant of the theme. FTL is a resource that can be controlled, and who ever controls the transport lanes, has, basically, all the power.

  2. Tyson Adams

    Is it just me, or is this article just an excuse to praise how awesome The Expanse books are?

    I think one of the main problems with sci-fi trying to be futuristic is that it keeps thinking of things in terms of today or yesterday’s ideas and problems. Which is why I think sci-fi is often best as allegory or satire or concept exploration.

  3. GeniusLemur

    “Warfare Would Be Impractical”
    Uh, warfare has ALWAYS been impractical, but there’s never been any shortage of it.

    • Oren Ashkenazi

      While warfare is almost universally awful, it has also proven a very practical method of various groups and countries to acquire resources and build power. In the Mexican American War, for example, the US seized most of what’s now the western half of the country, and California alone has contributed hugely to making the US as powerful as it is.

  4. Wheel

    Imagine that, in addition to humans, Earth was home to a species of sapient ostriches. They’d walk on two legs and use opposable thumbs, but that’s where the similarities to humanity ends. Like their mundane cousins, these ostrichians lay eggs, have feathers, and easily grow up to nine feet tall.

    My first thought was, are they delicious? How are the eggs? Could they be fitted with a saddle.

  5. Jesterr

    War is often fought for other reasons. Religion and power are two common issues. Culture conflicts, misunderstandings, taboo violations, politics, philosophy/wiring/mental issues… Ender’s game where the aliens don’t understand we’re intelligent until they start a war, and we can’t communicate til its to late. Bugs like in Starship Troopers, who mentally aren’t wired how we are. The Posleen from Gust Front, genetically made locusts…

    Plenty of ways to justify warfare.

    Trade is justifiable… If capital investment is expensive enough, or difficult enough, you’ll get trade. If resources are unique or scarce you’ll get trade. If investing in an antimatter factory is expensive enough, you’ll only get them on easily defended planets and in concentrations (econonic clustering… think silicon valley, hollywood, or Detroit during it’s hey-day.) If nothing else, _people_ can be a commodity too.

    With sufficient energy, fighting the gravity well and/or FTL are trivial expenses. Given those, there’s no reason trade won’t flourish in space.

    • Oren Ashkenazi

      I think you’ll find that with almost any major war, the conflict is actually over resources, and the religious or cultural justifications are added afterward. Or at the very least, that there are always major resource issues present along side cultural and/or religious justifications.

      As for trade, the issue is that as technology advances, we’re discovering more and more that fabrication is just a matter of energy. With enough energy, almost anything can be produced locally, and any society that can cross the vastness of space will have energy indeed.

      • Krssven

        Not sure you have a good argument there. Neither World War was over resources – the first was a complicated series of treaties that pulled everyone into a war they didn’t actually want, all because of one assassination. The second was because of the totalitarian, empire-building and racist hatred of largely one man, which influenced and entire nation (no, the economic situation of Germany between the wars does not count – economic problems alone don’t cause wars, people have to want them).

        There’s also the Korean War, which was as ideological a war as you’ll ever get. The US and China were only involved because of Capitalist/Communist loyalties on either side. Vietnam, where the US was only interested in one thing (that the Communists didn’t win).

        • Oren Ashkenazi

          While it isn’t talked about as often, both WWI and WWII were in fact largely over resources. John Green does a great job explaining the complicated resource issues of WWII, but the short version is that both Japan and Germany were relatively isolated nations that wanted the resources other nations had by virtue of empire or territory, and decided to seize them by force. WWI was similar. Germany had only recently come into existence as a country, and they were chomping at the bit to have a piece of the colonial empire that other European nations enjoyed. That was why so many European powers were entangled in treaties to begin with. The complicated treaty situation in 1914, and Adolf Hitler’s extreme xenophobia certainly contributed and made for good flash points, but resources were the root cause.

          Korea and Vietnam were outgrowths of the much larger conflict between the US and the USSR, in which resources were certainly very important. Both the US and USSR governments saw it to their benefit to have a friendly regime in Korea and Vietnam, and so they were willing to fight over it.

  6. Krssven

    A few of these ‘issues’ are a little weak. Warfare being ‘impractical’ and conducted by robots at interstellar distances is a very tired trope now, and doesn’t appear in most sci-fi these days. Why exactly would ships fight at such huge distances that anti-ordnance would be laughably easy? That rules out anything like a conventional missile or torpedo. High-velocity lasers would be shorter ranged, as photon emissions disperse rapidly over distance. Accelerated rounds might work, but all the enemy ship has to do is make a tiny course correction and the margin of error would widen to the point the rounds would miss by thousands of kilometres or more. No, fighting in space really would be fought at visual or near-visual ranges, simply because we are VERY good at stealth tech. The key tech in space will be cloaking emissions so that you could be sure of hitting your target only via eyeballing (or gravitic measurements). It’s this tech that makes Western naval and air power so effective. You have to detect something in order to shoot it.

    It’s also incredibly naive to assume that interstellar civilisations would have no reason to fight (this is also a trope from older works that doesn’t crop up much these days). As you tried to assert above, there’s always something someone wants. All it takes is for two peoples to encounter each other in the wrong way for interstellar war to break out. Humans are very unlikely to be the only, or even the most powerful, interstellar power in any given work. There’s also the possibility an alien race would rather have the nice real estate we have rather than search for years for another one. All possibilities.

    When creating my own setting, I simply answered these questions directly. War hasn’t died out just because we’re in space, and the first interstellar war is caused by humans assuming a (assumed to be) unmarked, unclaimed planet was just that (it was actually a border world of a territorial and much more advanced species). Communication is largely superluminal but requires a network of gigantic platforms to sustain and amplify the signals. Travel is at FTL speeds and requires enormous power, but not so large that it would power whole civilisations simply because the technology doesn’t ‘brute-force’ relativity. It rather bypasses it in a vaguely similar way to the Mass Effect drives from the games of the same name. Trade is entirely necessary, because some colonies are not self-sustaining and some are set up purely to generate income for more ‘civilised’ worlds. A lot of things such as food are grown locally (and even some of those produce surplus that is sold offworld), but unless the computer you want is specifically made on your planet, it has to be shipped.

  7. Nicole Montgomery

    I enjoyed the article a great deal, but I have to agree with a few of the critics–human beings, and by extension have always engaged in “impractical” warfare. The article seems to see the other reasons for warfare, whether ideological or religious, as the excuse, and resources as the reality, but often it’s just the opposite, or these things work in tandem. Which one is used as the justification depends on the spirit of the age. When people tell their government to only go to war over tangible benefits or threats (America fightng in Afghanistan, for example–terrorists!), then those become the justification, even if the reality is more complex and nebulous. But if the people support a war for a “cause” then that becomes the “reason.”

    Sometimes, of course, it really is that resources are the reason and the rest is smokescreen. The British holding onto India so long is a key example here–“We’re doing it for their sake,” when really something like 40% of the British economy was dependent on India buying cotton.

    I guess what I’m trying to caution against is depending solely on what’s reasonable or logical as motivations because sentient beings are too complex to be solely motivated by reason or logic.

    Except the Vulcans, of course.

    • Oren Ashkenazi

      If you’re interested, I would love to discuss how the current conflicts in the Middle East are about resources, because it’s a fascinating subject.

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