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Just For Fun: How to Invade an Alien Planet
Are you an alien civilization with a go-getter attitude, looking for some ripe planet to invade
? Here are some tips to ensure you don't end up like all the others out there who've tried and failed
. All we request for giving you this information is, should you successfully invade a planet, that you give us some of the fruits of your labor and possibly positions of power in your glorious dominion. Preferably far away from the planet we helped you invade.
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Phase One: Motivation and Planning
To begin with, put some thought into why
you're invading in the first place. If you're after a material good, is there an easier way to get it? Now is also the time to do some basic research on the target world in question, to make sure it's even worth the effort of conquering.
- If you're looking for some ridiculously common substance like helium, water, oxygen, etc., there are millions of lifeless rocks where you can get the stuff essentially for free, without the need to fight off pesky hostile natives. Aluminum? Uranium? Go mine an asteroid and leave the Puny Earthlings alone.
- Free advice: water is bulky. Even a fleet of a thousand mile-wide spaceships can't hold enough to make a significant impact on a planetary biosphere. If you need it for reaction mass and not to drink, see #1. In fact, if you don't need it for reaction mass and do need it to drink, also see #1 (sure, it's dirty, but you can clean it up with simple and comparatively cheap distillation—and probably get some nice salts, hydrocarbons, etc., in the bargain).
- If you're sufficiently advanced to cross interstellar space in the first place, consider investing some research into basic technologies like food replication. Harvesting native intelligent beings as cattle is dreadfully inefficient, and they tend to object. And if you are looking for a bite to eat, you might want to try abducting large, meaty animals instead of wasting your time with the boniest, least nutritious species on the planet—to say nothing of the only species on the planet capable of understanding what you're doing and taking exception to it. With guns.
- Corollary: If you do end up taking cattle (or sheep or pigs or whatever), you had better make sure that you either do it quietly or have indestructible ships, as farmers tend to be rather protective of their bovine (and ovine and porcine) property, and rural folk are the most likely in any country to be highly armed (particularly in the places that raise the most livestock). Either that, or you could trade. Even if you want to take the livestock only once and then breed them, you might want to give us some token payment in exchange for our knowledge of animal husbandry and genetics - chances are, you'll have a lot of negative outcomes with our animals if you don't have this information.
- Similarly, unless your robots are really dumb and only sentients can do a job you can't or won't, don't bother going to other planets to enslave the population. Better yet, buy/steal their automation technology instead! (By the way, how did your species get into space without it?)
- Check the air and water first to make sure they aren't toxic to your kind. If you're invading a Class M planet but your species has a lethal reaction to H2O, you're about to get a remedial course in natural selection.
- Take samples of the plant, animal, and microbe life and do controlled studies to make sure your mighty invading army won't be killed by a bacterium. Further, test all of these samples to ensure that they don't have non-lethal but disabling or embarrassing effects on your biology like ginger making your troops horny or sour milk making you drunk. Lastly, cross-check your and the invadees' relative scale. There's nothing more embarrassing to the average galactically-feared alien conqueror than commanding your vast battlefleet across the interstellar void and into a screaming dive upon your target planet with all weapons blazing, only for it to be swallowed in its entirety by a small dog.
- Bring a fully-equipped scientific staff to deal with any unexpected issues that may crop up (and they will). Treat them with respect so they don't revolt on you.
- If the air, water, or biota are hostile, and you can't find a solution that doesn't involve covering your people with inch-thick environment suits, leave.
- Corollary: If the ecosystems are hostile but you're after something underground, consider burning the offending biospheres off with an orbital bombardment. Your guys will still be in life support suits, but you'll save money on security.
- Study the history of your target planet - you shouldn't even need to make contact for this as any planet technologically advanced enough to be a threat to you is going to be broadcasting information like crazy. If they've got a history of thwarting invasions and bringing unstoppable galactic juggernauts of destruction to heel, you'd better be damned sure you know a few tricks the other saps didn't. If not, and you have sufficiently skilled diplomats, consider just asking for whatever you're asking. Maybe you can even offer the natives a big enough bribe and point them at your enemies.
- Caveat 1: if the inhabitants of your target planet appear to possess implausible levels of martial prowess, be sure that the information you're observing is non-fiction.
- Caveat 2: if the inhabitants of your target planet are technologically advanced enough to pose a threat to you and also apex predators, expect anything and everything to be something they can figure out how use as a weapon against you.
- Once you've gotten an idea of what the natives are like, never make assumptions of how rapidly they'll advance between now and the invasion. If you come to a planet assuming that they'd still be wielding sticks and they're actually developing the atomic bomb, you're in real trouble. Especially if they are now arguably more advanced than you.
- If your research is performed from a distance such as your home planet using high-powered telescopes, note that you observe light patterns as they were when they were projected from the alien planet. If you are doing your recon from two hundred light years away, even if your travel time was zero, the data would be two hundred years out of date.
- If your plan is to terraform the world into a climate or environment more suitable for your own kind, once again, step one is to see if some uninhabited rock will do. If you're sure it won't, then exterminate the aboriginals before commencing operations - you'll be destroying their civilization regardless, and aboriginals are often shockingly adaptable and determined to survive terraformation.
- If your plan is to, by one means or another, terraform the planet before you arrive, take the time to scan the hopefully-hospitable planet before approaching. The locals may have interfered with the terraforming process, and at least a few have probably survived, and if - or more likely, when - they figure out you were responsible for the end of the world as they knew it, they will be pissed.
- If you have an insatiable desire to eat souls, have you considered manufacturing them? Souls are software objects: investing in the mass simulation of innocents is both cheaper and safer than eating out. note
- If your civilization is trying to recover a piece of Lost Technology last seen in this sector of space, always, always, always assume that the natives have found it, reverse-engineered it, or know how to use it, and plan accordingly. If you believe that your invasion will be utterly destroyed if the natives use this technology, just don't bother.
- If you are biologically compatible to any degree with the aboriginals, even if it's just being able to consume one another's flesh for nutrients, then make sure not to ignore the issue of germ warfare. Send robotic or expendable scouts in first to collect samples (see the abduction recommendations in the Meeting the Locals section for details), and run a thorough vaccination program on anyone who will come into contact with the natives.
- Corollary: try infecting the local population with a disease that your own people are either mostly immune to or only mildly inconvenienced by, preferably after inoculating your own troops against the indigenous pathogens to avoid a massive backfire. If you're lucky, their population will be devastated and their civilization in utter chaos, making conquering quite easy and leaving large swaths totally unoccupied.
- You may think it brilliant to simply go back to an earlier time in history; before your target victims discovered warp-speed, phaser guns, and teleporters, and the height of their technology are snazzy digital wrist-watches. Just remember, chances are you won't be the only one trying to alter history. And folks won't be pleased that you're trying to destroy their ancestors. In addition, be aware of the tendency of primitive civilizations to have access to magic. Nothing breaks morale more than having half your fleet taken down by a wizard on a hill.
- Can you trade with the locals instead of conquering? Many planets even practice slavery, and they certainly will like your new technology. Just remember to trade them microwave ovens, not death rays... and you may even want to rethink giving away that microwave oven tech, unless you fancy the risk of being toasted with MASER weaponry.
- Check the enemy for signs of a Alien Monitoring Agency BEFORE you invade. If they have a Dangerously Genre Savvy one, don't bother. If however the agency is non-existent or is A Half-Dozen Guys in a Basement, you may be okay. If one of its agents is a certain Fox Mulder, your chances are about 50/50: although he knows exactly exactly what you're doing, there's a good chance nobody will believe him anyway.
- Look into native legends and myths. If they indicate that your intended conquest has an alien protector, a secret military unit that has already made contact with far more advanced alien species and defeated them by employing guerilla tactics, a stockpile of alien artifacts, or some other recurring righter of wrongs, you may want to look elsewhere.
- Similarly, keep a constant watch for: a small, innocent-looking blue box, covert military units with "SG" in the name, mecha sporting Cool Shades, saucer-shaped cruisers, giant robots, well-dressed men in sunglasses, starships with ring-shaped FTL systems, vigilantes in colorful costumes who casually defy the laws of physics, a power-armored warrior with huge spherical shoulders, or anyone in power armor, even if they're bespectacled physicists with crowbars. Spot any of these and you're better off staying home. While you're at it, also check for any uninvited guests masquerading as local machinery; such party-crashers usually have drama of their own, and you do not want to get sucked into it.
- Exception: If you think you can trick the governments of the world into doing something horrific enough to cause this guardian to turn away in shame, you might narrow your opposition down to some Welsh bisexuals. Still a tough fight, but it's better odds. Althernatively, if the protector works secretly, see if you can expose them without tipping your own hand; the natives may deal with your problem for you.
- At the end of the Planetary-solar rotation cycle, your best bet may be to remember Rule of Acquisition #35: "Peace is good for business." It's much cheaper in the long run to trade than to invade. If you use this route, however, keep your deals square. Otherwise you'll face a threat worse than any armored or caped or scarfed hero: lawyers.
- Before you even start shooting, study the native technology to make sure that your super-advanced weaponry isn't startlingly inferior to its mundane equivalent.
Phase Two: Meeting the Locals
You know why you're here, and you've arrived. Now it's time to say hello to your future conquests and build goodwill and trust you can later betray.
If subtlety isn't your thing, feel free to skip on to Phase Four: Conquering the Locals. Alternatively, if you wish to remain hidden while infiltrating the natives' society, skip to Phase Three.
- Hire a really good cultural interpreter to help you get around those unfortunate misunderstandings that occur when you are dealing with alien language and customs. It really damages any occupation attempt when the first thing thing the locals hear you say is how your hovercraft is full of eels rather than how your spacecraft is full of orbital-bombardment cannons.
- Don't remark on how ugly, short, tall, overlimbed, underlimbed, weak, stupid, stinky or non-spectral the natives are (at least not in public) as it's never a good thing to insult the hosts.
- If you really do come in peace, expect the locals to speak a very different language from yours. There will have to be a great deal of time invested in decoding and learning the mode of communication well enough to establish diplomatic relations.
- If you don't come in peace, don't even bother and just start invading (see Phase Four). Any time you spend learning about and infiltrating them via subterfuge and public relations is time you are giving them to learn about you and your weaknesses and limitations via spying, ill-conceived dropped factoids, and basic behavioral habits.
- Don't pretend to be "just passing through" when you have clearly studied the native culture well enough to look exactly like them, speak the language fluently, and understand their societal and cultural issues.
- Helpful hint: appearing out of nowhere over dozens of cities at once in giant ominous spacecraft is not good for public relations. Figure out how the natives communicate and talk to their leaders a bit first. Give them time to prepare for the culture shock.
- Don't try to look too much like the natives. Uncanny resemblances breed suspicion. Unless there's some kind of weird universal convergent evolution going on, in which case explain this ahead of time.
- If you are really reptilian monsters underneath those disguises, have a contingency plan for when the natives figure this out. Better yet, come as yourselves. The natives will get over it faster than if they find out you're hiding something.
- Corollary: The great thing about being up front about your non-nativeness is that no one will ever imagine you can use spies, moles, saboteurs or sleeper agents. Won't the natives be surprised when anyone from the janitor to their supreme leader can be one of you?
- Don't try to lure the natives with the promise of sex. Sooner or later they'll actually want some and; (a) figure out you can't provide; or (b) do it and end up giving birth to some weird Half-Human Hybrid with magical powers that will be turned against you.
- If the natives are attractive to you and there are enough genetic and physiological compatibility factors to make mating feasible, win them over by offering them a life of leisure, luxury, and pampering. Do not attempt to abduct and sexually enslave them - neither they nor their mates will appreciate that very much.
- Don't try to supplant the natives' religion. It never goes well. Instead of friendly natives, you'll end up with a bunch of mindless grovelling sycophants, a bunch of violently outraged fanatics who will stop at nothing to kill you, or both.
- If you're sending scouts down to the planet, make sure none of them are the type to sympathize with the natives and either defect or sabotage your plans.
- Corollary: don't mistreat or kill your own workers. They will defect and they will tell the natives exactly how to crush you.
- Exception: if your civilization is congenitally racist and even the lowest peons regard themselves as better than all other species, you might have a bit of leeway. But be warned, sometimes they can go soft on you and start empathizing with the native animals.
- Remember, robots are physically incapable of disobeying you if you program them right. Use them to scout instead.
- If normally objective scientists suddenly claim an ostensibly supernatural phenomenon, such as the natives' version of God, is both real and scientifically verifiable, do not dismiss them out of hand, no matter how much easier ignoring it would be. Halt all operations that might be affected, have their results verified by independent scientists, and tested by another group of scientists, with full procedures observed as much as possible. If they are correct, modify or cancel operations accordingly. Unless you're feeling confident that your death rays work on deities.
Phase Three: Infiltrating the Locals
Phase Two is complete, and the natives are now convinced of your good intent and benevolent nature. Suckers. While you keep the public relations campaign going, now's the time to get to know these saps a little better through quiet abductions and vivisections, while your agents worm their way into positions of power.
If all goes as planned, you can skip ahead to Phase Five once you're done.
- If you wish to "learn" about the anatomy/biology of the locals before destroying them (and still wish to remain hidden), make sure you abduct specimens who either won't be missed or won't be reported missing, i.e. a homeless local or someone who lives in the middle of nowhere.
- Unless you implant some sort of mind control device into the specimen without killing them, never, ever release them back into the general public if you don't want your cover blown. Although, depending on the species, the others may or may not believe the abductee. It still doesn't hurt to not take a chance.
- Also, be absolutely certain that the abductee isn't an associate of a future La Résistance leader and/or member. Warning signs are if male abductees are skilled enough in all forms of combat to make abducting them in the first place problematic, or if female abductees are irresistable to young male members of their species.
- It may be easier to steal (or even purchase) some of the native's own studies on their biology, they've spent much longer than you learning their own anatomy.
- Any infiltrators should be closely monitored for defection. Should there be strong or conclusive evidence of such, they should have their security clearance revoked immediately and be detained in a holding facility, preferably far away from the target planet, not guarded by anyone they could ever possibly have met, and certainly not anyone sympathetic. And by immediately, we mean "have that changed in the system now." Just because you took away their key- and identification cards does not mean that they don't have another stashed away somewhere.
- If your goal is to take over the natives' bodies to use as your own, then your entire invading force is Moles. You are in the perfect position to conquer without anyone even knowing you're there until it's too late; overt acts of conquest, however, Esplin 9466-alpha, will just alert the natives to your presence and get them to mount a defense/resistance. On the other hand, you're in an ideal situation to use a sufficiently xenophobic and violent host species to do the dirty work of eliminating your interstellar enemies for you.
- Don't try to break up the inevitable La Résistance with heavy handed police state tactics. Ignore them — if your Masquerade is good enough, nobody will believe them.
- If the planet's defenders are low in number and ill-protected civilians, don't try to take them out in open combat. Local assassins and mob hit contracts work much better due to sheer experience in killing their own, and can't be stopped or detected by anything specialized to fight or detect you, so, before doing anything else, just bribe an amoral greedy native to take out his own defenders first, and make sure they finished the job. Then invade properly, again beginning with areas the defenders couldn't access if they were still alive (assume that they survived just in case, it won't hurt).
- If for some reason you can't identify the defenders, don't waste too much time on fruitless hunts for them, go ahead with the invasion and carpet-bomb La Résistance's area of operation.
Phase Four: Conquering the Locals
Maybe subtlety isn't your thing. Or maybe your covert operations have been exposed and the natives are starting to fight back. It doesn't really matter, because you've just entered the most entertaining phase of your invasion!
- Rig any of your technology that the natives could possibly capture with a foolproof remote-controlled self-destruct mechanism. Your technological advantage in combat exists only as long as you and your allies are the only ones using said technology.
- Make sure your infantry weapons don't have infinite ammunition. If the natives capture them, it will come back to haunt you. The best course of action is (if you can give them bottomless magazines in the first place) to use gene-locking to limit them to your troops.
- If your invasion armada has a mothership, make sure it's indistinguishable from the rest of the fleet, doubly so if its destruction would disable your armed forces. And give it decent enough telecommunications to stay in orbit where it can't be taken out by a dozen grunts with assault rifles.
- Corollary: Expect the best native tactician to spend hours studying recordings of your maneuvers searching for weak points. You mothership should not be recognizable even under this level of scrutiny.
- Second Corollary: If you absolutely have to have an ostentatious mothership, have at least one class of ship that is bigger and more obvious, or make it part of a regular class of ships. To many civilizations, Bigger Is Better is usually an indicator of major firepower or command, and will tend to focus efforts on them.
- Third Corollary: A single small ship hanging back from the main engagement is also an obvious target and therefore a bad place to command your operations from, especially since actions against it will tend towards using a Ragtag Bunch of Misfits who may well be more effective than the regular enemy force.
- Fourth Corollary: Maybe you should go ahead and give your mothership, and the rest of the fleet, your finest stealth technology.
- Put a firewall on your Master Computer so they can't disable your Deflector Shields with the Melissa virus. Enemy hackers will try to break into your computers and destroy them with a Computer Virus. Sometimes it's because their technology was reverse engineered from yours, and sometimes... well, sometimes they just get lucky.
- If an older model scout ship that you lost contact with decades ago suddenly shows up in the middle of your invasion and wants to dock with your mothership, don't let it. Quarantine it and make sure that it's not the natives pulling some trick on you. In fact, just shoot it; even if it is the pilot that was shot down, they've probably either gone native or developed Stockholm Syndrome by now. Plus the guy was dumb enough to get shot down in the first place.
- If you are the kind of aliens who prefer to seed planets with The Virus rather than land and conquer, when you do follow up in person, don't just assume that your virus worked perfectly and come without any kind of defenses.
- If the only threat to your rule is isolated or tied down somehow to a single geographic area such as a city or country, take care of them last - get entrenched first. Conquer everything out of their range of protection first, then lay siege to the remaining area. Use your now-superior amount of the planet's resources to overpower them with sheer numbers and superior weapons. Both, not either.
- Addendum: Some particularly hardy specimens will continue with guerilla warfare even after this point. Carpet-bomb the area when you've got him pinned down. Try rodding them first, so you can go in immediately afterwards. If you have sufficient quantity and shielding, try using free-neutron emitters. If either of those don't work or are unavailable, then go to nukes. Preferably from orbit. After all, it is the only way to be sure.
- If you do end up having to fight La Résistance, consider using your advanced technology to build some decent, reliable ranged weapons. Hand to hand combat is so last century, and the natives will probably outnumber you. Exception: If shield technology has developed in such a manner that only slow objects can penetrate them, guns are, of course, useless, and you may freely ignore the above advice. However, should there be situations where the enemy is not using/cannot use shields, be sure to have ranged weapons in reserve.
- Don't commit your entire force to the first wave. Keep reserves, including your high command, at a safe distance. If the natives are pushovers, you haven't lost anything. If they're tougher than expected, you've got The Cavalry to turn the tide. If they find an Achilles' Heel, the second wave can figure out how to counter it. If all else fails, you've got a way to retreat.
- Recall that a planet is not a city, and thus any attempt to conquer one is roughly equivalent to a world war and not a small battle, and that planets, unlike cities, can be and usually are entirely self-sufficient. Make sure that you have either sufficient technological superiority/firepower to render any of the natives' numerical and logistical advantages useless, or get yourself a billion-soldier army, a million-man planning department, and get ready for several years of potentially fruitless hard slog.
- Remember, just because you've destroyed the defending fleet in orbit doesn't mean you control the planet: "You can bomb it, you can strafe it, you can cover it with poison, you can turn it into glass, but you don't own it unless your infantry's on it and the other guy's isn't." In other words, despite your victory in the void, you probably don't have a single boot on the ground; the planet is thus still entirely in the hands of your enemy, and therefore not conquered and still hostile. Now you have do decide: Do you even want the planet? If so, do you have to keep the surface intact and the natives alive? If you think that the answer is "yes" to either question, see immediately above. Is it worth it given the cost? (Don't succumb to the Sunk Cost Fallacy!) If you don't want it or if the cost is too high, just bombard it from space before the locals send their stockpile of ICBMs your way.
- Make sure you didn't wake up other alien groups while duking it out or provoke feint attacks. If the planet is capable of supporting carbon lifeforms, there's the potential of precursor civilizations coming and starting a two-way war with you.
- Similarly, beware alerting any sort of Intergalactic Space Police, especially an elite stateless one handpicked for their ethics and fearlessness with the imagination to use their standard wonder weapon to maximum effect. Sure, you might be able to take out the local opposition, but can you do it before they can call for backup?
- If your objective is to conquer the planet and Kill All Humans, just do it. Don't beat around the bush — if you've traveled across light-years to get here, you've gotta have some pretty decent weaponry. The longer you wait under the pretense of being friendly, the longer the natives have to organize a resistance and find your weaknesses... or call for help.
- Corollary: If you are going to Kill All Humans, damn well finish the job. Those scattered bands of pitiful survivors may look pathetic and harmless now, but give them a few generations to build up their numbers and you have a bunch of determined, bitter opponents who are very good at not dying.
- Second Corollary: If your interest is not specifically in wiping out only the dominant race, consider orbital kinetic bombardment that will reduce your target planet to, at best, a blasted wasteland and at worst a pile of molten slag.
Phase Five: Ruling the Locals
The dust has settled, most of the fires have gone out, and your new subjects are getting used to the fit of their shackles. It's good to be the king. To ensure that you remain
the king, keep reading.
- The indigs have been figuring out how to govern themselves for longer than you, and have probably come up with some helpful suggestions on how to do so. In other words, Read the Freaking Manual.
- For Xenu's sake, if you have conquered the populace, don't take one of your enslaved locals to a preserved library full of technical manuals, scientific journals, treatises on military history, and inspiring historical documents, just so you can gloat about how none of it will help them. They always seem to stumble upon their version of the Declaration of Independence, and then you might as well just bring out the white flag.
- If you keep any of the locals alive, don't tell them anything about you, or especially your technology. Even if it's for one of your zany schemes, or you feel like gloating, or if you plan on killing them afterward. There's just too much potential for things to go wrong.
- For that matter, don't take the aboriginals as slaves or pets. They may look cute and/or harmless, but it's just not safe in the long run.
- On the other hand, providing good living conditions, health care, and good pay (in currency worthless to you) can work quite well so long as your own people don't have obviously superior living conditions. As slaves, aboriginals are nothing but trouble. As "valued employees," aboriginals may prove surprisingly useful.
- Pay attention to your conquered territory. If you're not going to administer it yourself, at least garrison it with your own people. Assigning one set of slaves to keep an eye on another is just asking for trouble. If you can't spare anything but a surveillance drone, at least be smart enough not to put it on a predictable schedule.
- Use quislings well. They work great for putting a native face on your policies, and sentients take orders better from their own kind. Some native will be willing to help the occupation in exchange for luxury for their family and very little real power.
- At the same time, keep a close eye on any turncoats that have joined your side. If they're willing to betray their own species, their words of loyalty aren't worth squat; reward them appropriately. And some of them aren't really working for you at all.
- On the other hand, don't entirely distrust your turncoat lackeys. They can be used to mask your rule with a "local" face. The more you keep the same under your rule as when the planet was independent, the less the locals will even notice that you're there, and the more likely they'll dismiss La Résistance as paranoid lunatics.
- While brutal dictatorship is the most obvious and well-tested method of governing an occupied planet, have you considered unlimited freedom to indulge in consumption, booze, drugs, sex, food, gewgaws, games, idiotic music, and other forms of entertainment? (Internet access is particularly good for this purpose.) Even if it doesn't turn out to be cheaper than your Secret Police, it will pay off by utterly pacifying the populace, who will be so busy buying, eating, drinking, playing, and fucking that the few people who might have the will to stand up against your regime will be a couple of scattered, self-righteous, egghead intellectuals. If you play your cards right, even they will be at a loss at how to overthrow you, consoling themselves with simply being unhappy as a small act of rebellion.
Phase Six: Worst-Case Scenarios
Seriously? We made you this guide and you still... alright, stop panicking, let's see if we can salvage this fiasco.
- If you are not really strong enough to conquer the planet, but are instead faking superiority in order to hide a Weaksauce Weakness or Achilles' Heel, have a plan for the natives figuring this out. Even if it involves begging for mercy, it's better than dying. Who knows, they might even help you willingly.
- If there's a stronger alien race out there that you're fleeing from because they are even nastier than you, don't go out of your way to antagonize the natives if there's any chance they could help you.
- If there's a stronger alien race out there that you're fleeing from because they are hunting you down for the planet-looting vermin that you are, finish your work quickly before they show up and recruit the natives to their side. Don't count on your Propaganda Machine working.
- If, despite all your preparation and technology, you're losing the invasion, be sure to wipe your starmaps. The last thing you want to do is give those little bastards directions to your homeworld so they can launch a punitive invasion.
- If you are forced to cut your losses and call off the invasion, make sure you either take all your technology with you when you leave or at least set everything you have to leave behind to self-destruct. Not only is leaving advanced technology in the hands of a lesser species bad form, but it'll come back to bite you in the ass when they figure out how to travel beyond their solar system.
- In case of complete rout and really serious worst case scenarios, make sure you have a Death Star on hand or have bought a planet buster from a friendly empire. Sometimes you just have to cut your losses, accept that you can never conquer Earth, and just blow it up. Of course, watch out for small groups of plucky heroes in or out of spaceships - because those guys will always manage to blow up your Big Death Thing.
- Above all else, Know When to Fold 'Em. Know when to walk away. Know when to run. Sometimes, it's just not worth it. And if you absolutely HAVE to wipe out the planet for your own survival, swallow your pride and go for the Pyrrhic Victory where you wipe out the entire planet and just forget the resources.
If instead you want to destroy the place, go to Why You Should Destroy the Planet Earth.