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Theories on Planetary Invasion

Problems of strategy, logistics and the subsequent occupation of a well developed habitat.

The Concept

The concept of invading the planet of your enemy and subjugating it with raw military might alone is an appealing and enduring concept of science fiction. Heavily romanticised, few texts deal with the issues one would encounter with not only defeating the security in place around said planet, but also the following ground combat and occupation.

Usually, the be all and end all of a planetary invasion comes with the defeat of whatever meagre security forces are arrayed against the invader before the planet and all its inhabitants submit meekly to their new rulers. The successful invasion is then usually used (in the case of the protagonists) as a badge of achievement in defeating their evil nemeses or (in the case of the antagonists) a crushing blow against the forces of good which then must rally against their foe.

If only the truth were so simple.

For the purposes of this theory, we will assume the targeted planet be a relatively isolated locale – separate from any vast interstellar powers but nonetheless reasonably well protected by an array of orbital and ground based defences while at the same time being well populated. In other words, a heavily industrialized world – much like modern earth except with more guns pointing spaceward. We can class this example planet as among the most difficult types of planet to conquer simply because of the state of its development: its size and massive number of inhabitants. Differing situations may modify the content of this guide and it is not meant as an absolute be all and end all. For example, a small, single colony on a lifeless asteroid is obviously far easier to deal with than the planet we shall be using throughout this article. The actual Military Assault of a Planet is detailed in a companion article.

The term “Empire” shall be used throughout this document. Though the same principles apply to a commonwealth, space republic, etc.

Why Subjugation?

Naturally, if you intend to conquer a planet in the first place you must have some reason for doing so. The time, resources and planning involved in such an undertaking are not simple and not small matters. Indeed, in many cases – unless you’re hell bent on enslaving all traces of sentient life you encounter – it may be better to just live and let lie.

So, why would you attempt to conquer a planet? One of the main reasons, perhaps, is the planet itself is in a relatively high stage of development but nevertheless is not a player on the interstellar scene. You wish to bring them into your fold before they do get into space and become a royal pain in your backside. This is as good a reason as any, though you should at least have plans of using them once the invasion is done with.

Secondly, perhaps they stupidly attacked you or a war has been going on for some time. In either case, if you have time to think about invasion (rather than outright devastation of the planet in question) then you must be winning. Unfortunately, a hostile population is far harder to subjugate than a neutral or friendly one and devastation or genocide may essentially be your only options.

Finally, and mostly likely, the planet is possessed of some resource you desire. Be that a particularly advanced technology which you don’t possess (and they won’t give you) or more basic resources such as natural minerals or agricultural space. In any case, you must realise what you desire and seek to subjugate the planet without actually eliminating your reason for attacking in the first place.

Prelude to Subjugation

Firstly, any prospective empire would do well to try and establish peaceful relations with the planet. First contact would likely be conducted by a scouting vessel or emissary of sorts. It is here that we come to the most fundamental aspect of conducting a successful planetary invasion: you do not deal with the people of a planet, you deal with their government!

Also, it is important to note that your prelude to subjugation is also where a great deal of information gathering takes place. You should attempt to garner as much knowledge as you possibly can about your intended target. Military composition, strength of their defences, their level of technology, the attitudes of their population - even their prevalent religion and favourite brand of soap should be documented. All of this information may prove vital to your success…especially if you can somehow infiltrate their global network (cyber-warfare is given brief mention in the companion article).

Dealing with the Government
The government is assumed to be a significant ruling body. Nominally, they will command respect and maintain relative peace within their boarders (which, hopefully, will be the entire planet). The aim is to negotiate and subsume the government into your regime – the majority of people will follow their leaders. It is important not to replace the government until the planet is well used to living under your rule. Gradual change is a necessity because it preserves the equilibrium. A society has no reason to rebel if nothing about their life changes.

Dealings with the government of a planet should not, at first, include force. When presented with force, force is the most likely response. Likewise, one should not try and impose their ideals upon the unconquered society – such an action should be a part of the gradual change mentioned above.

Subjugation through Incentive

The proper course of action is to show the government the benefits of joining your empire; how they can improve their own society through joining your own. This would nominally involve promises of wealth through trading opportunities, or technological benefits. The return for such “gifts” is as simple as obeying certain – what we shall call – “universal laws” that supposedly everyone must follow. In reality, these are your laws and designed simply to (over time) integrate their society into your own. The idea is to leave the “subjugated” planet in a relatively independent state to minimize discomfort with integration into your of life occurring naturally given constant contact with your culture. If all succeeds, it will be a peaceful transition into your fold; a successful victory without the expenditure of any resources on your part.

Naturally, this method will not work on everyone (or even a majority of people). The second option is to conduct a “corruption” of the ruling government.

Subjugation through Corruption

Firstly, realize the fragility of the human heart – specifically, greed. A government by necessity contains only the smallest fraction of a population on a planet this size. By promising personal wealth or power to those in charge it can become a simple matter to sway their opinions. The revelation that their planet has suddenly joined your empire can cause some measure of unrest, but with no actual violence or noticeable change in people’s lives, there should be minimal conflict. At this stage, it is important to proceed with the gradual pace of change outlined above.

Of course, greed is not the only way to corrupt a government. Depending on the technological prowess of your invading empire, it may be just as simple – or even easier – to conduct brainwashing, to replace those in power with perfect android replicas, clones with their memories but a loyalty to you, etcetera. These methods will function much as the bribes do above (minor unrest but an otherwise peaceful transition).

Naturally, after you have conducted a “corruption of the government” it is important to dispose of those in power and replace them. This will prevent people from discovering your involvement – the pretext of such a replacement could be anything from the current leaders having to be “educated” (read, disposed) by going to an interstellar school or the like, they could be suddenly taken ill, or any other plan you can devise. Replace them with a good natured resident of the planet and assign a liaison a them. All should go relatively well.

Subjugation through the threat of Force

Not all governments are corruptible and not all governments will join on incentive alone. These stubborn fools obviously fail to realise the great rewards you can offer them if they would only reach out and take it. They must be dealt with; however, invasion is still a far off option. It is important to note we are still dealing with the government here and not the people just yet.

By demonstrating the futility of any form of resistance, it may be possible to “scare” the planet into submission. Your strength, real or fabricated, must be far greater than this one planet in order to accomplish this. Specifically, they must believe they have no hope of winning:

  • An “evil” government can most likely be persuaded to cease such vain resistance by playing on the fear of loosing their power (ala Subjugation through corruption). You must insist that their rule will end if they declare war and that joining your empire will instead increase their power.
  • A “good” government can be shackled by preying on their love of their people. Explain that not only will joining you be beneficial for their citizens (ala Subjugation through Incentive), but going to war will result in horrific casualties and human suffering the likes of which they’ve never seen.

In either case, a demonstration may be in order. In that case, we move onto the penultimate solution.

Subjugation through applied Force

If the threat of force will not work or they need a demonstration of your might, then you must carefully choose your targets. The best targets for such an operation are the military defences of the planet in question – specifically those capable of harming your warships in orbit (the actual methodology of this is described under Military Assault of a Planet). Hopefully, this alone will be enough to bring victory to your doorstep. If not, further bombardment may be necessary. However, at no time are ground forces to be deployed on a permanent basis. Your forces are for strike only.

The next targets if more applied force is called for are agricultural targets (if you want the world for industrial purposes) or industrial/population targets (if you want the world for agricultural purposes). The latter method (that of attacking population/industrial targets) is inefficient and unlikely to work if your target is the hearts of the people. It may, however, subjugate the government and facilitate your conquering of the planet. The former though, especially on a heavily industrialised planet (like our example), can prove highly effective. Never doubt the effect starving people to death has on enemy morale – a population that relies on you for food is a population under your control. A population that still refuses to give in despite having no food is a self correcting problem.

Under no circumstance though should you obliterate your reason for invading the planet. Nor should you expend the precious resources (by seeing your forces destroyed) which you are attempting to gain as made clear in “Reasons for Invading a Planet”.

However, if applied force fails there is one final option to employ.


When faced with a population that refuses to give in against all odds. One which is stocked to survive possibly for years or will not surrender unless you destroy your reasons for invading the planet in the first place warrants this solution. This is the last resort. The one thing you’d hoped to avoid because it makes your life very difficult in the long run…

The complete annihilation of every man, woman and child who dares stand in your way.

I must reiterate again that this DOES NOT involve a military invasion of the planet. The article on Military Assault of a Planet makes it painfully clear why this will not work. Likewise, your goal is the planet’s resources whatever they may be and thus wanton destruction is counter productive.

Here, with genocide, you aim to start over. The planet must be made incapable of supporting life or outright harmful to the current population. The primary method of accomplishing this would be a destructive plague or similar biological agent (no doubt artificially produced and tailored to the populace of the world you are conquering). Seeding the atmosphere with such an agent will all but ensure your victory.

In a similar vein, a chemical agent which contaminates or destroys the atmosphere of the planet will also prove deadly though the work required to make the atmosphere habitable again may prove extensive. Though this is of no consequence if you survive in a different environment to the natural inhabitants of the planet – as you’d have to do it anyway (in fact, altering the environment to one that sustains you could be your method of killing the population – two birds with one stone).

It’s also possible to simply cause massive devastation and destruction on a catastrophic scale. This method is usually very quick and very messy – perhaps being as simple as firing a few dozen nuclear warheads into the atmosphere for an airburst detonation across all major population centres. This is the sort of solution you use if you simply have no time to conquer a planet, or simply want to deny it to other people. A scorched earth strategy if you will.

After genocide, whatever resources you wished to claim are free for the taking. You are now open to engage in an extensive colonization effort that will pick up exactly where the previous inhabitants left off. Your aim is to make the planet self-sustaining and profitable after a genocide which should only take a few years at the most.

See Also

guide/old_articles/theories_on_planetary_invasion.txt · Last modified: 2018/01/14 16:49 by raz