In part 1, I described the enormous scale of a galactic empire. In part 2, I discussed the impact of FTL technology on the empire’s economy. In part 3, I wrote about the purpose of the empire, and ways it could be managed.
Now, I ask: how does our empire maintain military and political control? Feudal systems are popular in sci-fi stories, because they make interesting family/intrigue stories, but are only likely if an empire is fracturing, or if there’s a border area in need of protection.
Our empire could maintain a monopoly on warships, or all spaceships, and threaten to drop rocks on dissenters from orbit and/or blow away their orbital cities. If imperial ships are rare and/or slow, the planet can return to ignoring imperial directives once the ship leaves.
If our empire doesn’t want to fill a planet’s atmosphere with dust, it sends in the troops. With fast ships, it mobilizes a Normandy-style invasion. With slower ships, it puts out a call across the galaxy, and wave after wave of raiding parties land and trash the place until the planet gets tired of it and submits.
Is it possible to invade a planet with billions of inhabitants? The defenders are spread out across the surface — they’re not all protecting New Beijing (if they tried, they’d starve to death). Take away the third of the population who are toddlers, pregnant women, and the elderly. If the defenders don’t let women fight, cut their remaining numbers in half. The emperor can order a paltry ten thousand of his planets to each provide their ten thousand most capable soldiers. That’s a highly-trained one-hundred-million-man invasion force. Raise those numbers to twenty thousand, and the invasion force has 400 million troops. Raise them to thirty thousand, and you’ve got almost a billion invaders. Raise them to fifty thousand, and the defenders may be outnumbered. If the first landing fails, the transport ships go home and load more soldiers. Those single-planet rebels never had a chance.
Maybe our empire thought ahead when it was colonizing all those planets. It settled each of them with two or three ethnic or religious groups (or alien species) that hate each other. If imperial troops decide to step in, they’ve already got an allied force on the ground.
Maybe our empire is held together through non-military means. Local media programming is outlawed, and imperial news and entertainment reinforces a common culture. The capital is a giant university, indoctrinating upper-class kids from the subject planets. Conveniently, the kids are also hostages during their studies.
Maybe the governor of each planet is a clone of the emperor. Anyone who killed the emperor to seize the throne would be facing millions of angry planetary governors, and what kind of speech could a rebel governor give about how awful the emperor was?
One option to cut down on rebellions would be to let planets do whatever they want on the surface, and only control interstellar trade and prevent interplanetary warfare. I don’t think this would work under an empire with democratically-elected leaders. Today’s democracies don’t seem capable of staying out of any aspect of their citizens’ lives, and what if a planet did something reprehensible, like instituting slavery (or abolishing it, in a slave-holding empire)?
The concept might work in an empire where every habitable planet had its own species, or where a technologically advanced alien race rules over many others, as the emperor could say “That’s just how those wacky Eridians do things.” The concept might also work in an empire run by an incomprehensible AI and its robot army. The AI could rule benevolently, or the organics could live in terror, not knowing when their actions would cross the AI’s line from “ignore” to “genocide”.
Would a hands-off trading cartel sit by while two armies on the ground devastated and looted a planet without decisively engaging each other? Would it sit by while a planet instituted communism, reducing economic output by 95%?
One final topic: if our empire is multi-species, what role do humans play? I’ve seen many variations. Sometimes, humans conquer the galaxy (see my review of Mike Resnick’s The Olympians for his take on this). I read one story where humans conquered the galaxy, and the aliens said ‘Tag, you’re it. Now, it’s your turn to manage this whole mess until another primitive species discovers interstellar travel.’ (Leave me a comment if you remember that story). Other stories have humans as one of several major powers, humans as a minor species with some symbolic/historical significance, or humans as completely insignificant.
Unless I have another brainstorm, this is my last post in the series. Now, get out there and write some galactic empire stories! Also, leave me a comment about how I’m thinking too small.