Imagine a future where combat is common in space. All parties have signed an equivlent of an updated Geneva Convention contract, to regulate warfare and make it as 'humane' as possible.

One of the primary concerns for this new contract is to habitats, which are defined as both planets and non planatary civilian stations (like a space station). These coventions include things such as outlawing the use of any weapon on a habitat that would kill, or render inhabitable, a non-trivial percentage of it's peoples/lands. This does things like placing strict limits on weapons weapons that can be used on 'ground' targets. Coventions also give certain, more limited, protections to 'satilites providing imperative civilian or humanitarian services which are not also being used to support military objectives', so things like power sats, sats that support tearforming of planets, emergency civilian comms etc.

One particular concern is 'accidental' damage of a habitat. The high energy weapons used by ships are powerful enough that a stray shot striking a planet could render large parts of the planet uninhabitable. Even large debris from a space battle could strike a planet with enough force to be the equivlent of a nuclear strike.

Thus I'm wondering what would be reasonable conventions for space combat to ensure that these habitats and people on them are protected in the event that a battle over the habitat takes place in space. I'm looking primarily at protecting these habitats from incidental risks of warfare, not from intentional attrocities.

For example I assume all space combat would have to take place a minimum distance away from habitats, but how far would that distance have to be? Would it depend on the type/size of the habitat?

Would there be rules that prevented fireing at, or positioning, ships such that the habitat is behind them, to avoid missed shots traveling towards the habitat? or even requiring battles to take place near another massive body so that the suns gravity well will collect debris? Gf not how does one prevent debris from a battle from potentially being sucked into a planets gravity well and harming the people on the planet? How would more fragile satilites be protected?

What other policies would be required to protect fragile habitats from battles over them in space? This includes preventing the rules from being easily exploited for tactical advantage by either side.

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    $\begingroup$ In the Honorverse they have the Deneb Accords, which are a sort of updated Geneva Convention, which, among others, forbid nuking inhabited planets from orbit. On the other hand, in the same series, strategically important civilian space stations (for example, the traffic control stations of wormholes) are occasionally attacked (or at least threated with attack) and captured. Anyway, I'd say that imagining the laws of war in space is the writer's task, and you should ask about specific aspects of the proposed rules. $\endgroup$ – AlexP Aug 8 '17 at 16:00

from https://en.wikipedia.org/wiki/Geneva_Conventions

The Geneva Conventions are rules that apply only in times of armed conflict and seek to protect people who are not or are no longer taking part in hostilities; these include the sick and wounded of armed forces on the field, wounded, sick, and shipwrecked members of armed forces at sea, prisoners of war, and civilians. The first convention dealt with the treatment of wounded and sick armed forces in the field.[20] The second convention dealt with the sick, wounded, and shipwrecked members of armed forces at sea.[21][22] The third convention dealt with the treatment of prisoners of war during times of conflict; the conflict in Vietnam greatly contributed to this revision of the Geneva Convention.[23] The fourth convention dealt with the treatment of civilians and their protection during wartime.[24]

I like the way they did something like this in Star Trek with the Khitomer Accords. Clearly something bad went down that was enough to horrify both sides and have them come to an agreement. It was never clear to me watching TNG what exactly that event was, although I see in the link it was the destruction of a populated Klingon moon. Those accords are invoked from time to time to explain why this is done or that cant be done, or (for the second Khitomer accords) why these aliens have subspace weapons that no-one else in the Trek universe does.

No-one reading a fiction wants to have laid out a bunch of dry language of an accord. So: back into it the exciting way. Create the event that shocked both sides and led to the accord. You could refer to this event in passing or describe in a paragraph what happened. Then the nature of the accord follows from that - a code of conduct intended to prevent a recurrence of this tragedy. Better - introduce your code of conduct by having someone violate it or intend to, and then you can mention why the code exists at all and what happened to other people who violated it. That keeps things moving.

  • $\begingroup$ There are actually two Khitomer Accords, the first was portrayed in the Sixth Movie (The Undiscovered Country) which ended open hostilities between the Federation and the Klingons. The second one was sometime in the 80 year gap between that movie and the TNG era and seemed to establish an alliance between the two powers and a weapons ban. There was the Selondis IV convention, which basically is rebranding the Geneva convention on POW rules, but all that mentions is torture of POWs is illegal (if one qualifies as a POW, which didn't help Picard as he was officially rogue). $\endgroup$ – hszmv Aug 8 '17 at 19:17

I have my own space-Geneva conventions. It is based a few basic notions which might inspire you.

You are accountable for every missed shot. That encourages people to fight close range where a miss is unlikely, kinda wait to see the white of their eyes situation. You can still miss, and then it's on you to either render your projectiles harmless, or accept that you might commit a war crime somewhere and somewhen else.

In planetary defense, defenders set the tone. Attackers are allowed to reply on the same order of magnitude. WMDs aren't forbidden, but you can only use them if defenders use them first. At that point, they unleashed hell on their doorstep and that's on them.

Attackers cannot target civilian population purposefully. This preclude using meat shields as well. If defenders do use civilians to hide behind, that's on them. You could apply the rule to civilian infrastructure as well. But again, placing an AA gun on top of an hospital makes the hospital an acceptable target.

A ship can exit combat and must be left alone. Depending on the outcome of the battle, they'll either go home or become POWs. Exiting combat is permanent for the duration of a battle. That ensures ships can survive rather than being totally destroyed, which could limit debris significantly.

You can't prevent debris but you could conceivably have clean up agreements, like a fund contributed by both parties and overseen by a third, neutral party. That makes clean up costs a non-problem.

The key is that rules should be designed to protect both sides. Defenders know they won't be genocided, attackers know there is always an appropriate force they can use. If you need further enforcing, I use the third, neutral party aforementioned as a tie breaker, i.e. they won't pick a side and won't severely unbalance the conflict as long as everybody plays nice.


I think other people have done a good job of going into the probable genesis of such a treaty, so I'll instead go over the clauses that I suspect would be necessary to create the environment you want, as well as the obvious issues with them.

As I see it, there are 4 sorts of weapons which are particularly and obviously destructive to an environment, some of which are more useful than others against military targets. They are as follows:

Bio-Weapons. This includes both chemical weapons and bio-engineered nasties, which would most likely take the form of Viruses and Bacteria but for completeness sake should include genetically engineered animals as well (no Xenomorphs allowed). These sorts of weapons are a lot more effective on Civilian Targets than military ones and have the potential for spirally wildly out of the control of their creators, so it's not too hard an ask to ban them.

Relativistic Weapons. This was covered in another answer, but any material of even extremely minute mass can pack incredible force when accelerated to speeds in access of several KM/s. Such a weapon could casually destroy a space habitat, though it would be a lot less effective on a planetary body with an atmosphere. Worse still, due to the speed of the projectile, it's unlikely that active defenses would be effective against it. It's an effective military weapon, if a potentially expensive one. I think it would be a hard sell to completely ban this sort of technology, but you could theoretically put limits on the number of them, their total power output or perhaps the places where they are acceptable to deploy. If nothing else, it'll be pretty obvious if a space habitat gets hit by one, so assigning blame if one is used inappropriately shouldn't be too difficult.

Gravity Weapons. This is where things get really tricky. Any large mass, when thrown at a larger mass, is going to cause some pretty terrible destruction. All you really need is the thrust to maneuver a comet, asteroid or space colony into a decaying orbit and you're going cause wide-scale damage. It's so easy that a military power need not even be involved. The good news is that, once again, this isn't actually a great weapon against military targets. It's slow enough that a military installation can probably move. Even if they can't, it's not going to be particularly accurate and a fortified military base would probably survive a near (in planetary terms) miss. The real problem is that this is an effective terror weapon, both because of the results and because it's so easy to do.

Super Weapons. This is something of a catch-all, which is why I've listed it last. A straight ban on any weapon of sufficient size or power would be necessary for obvious reasons. History has shown that major powers will try to cheat this sort of thing, but skirting the rules is a lot better to openly violating them. In this case, any platform that gives a military power the ability to attack without fear of reprisal will make all other restrictions start looking more like quaint suggestions than intergalactic treaty. With this in mind, pretty strict rules should be in place to make building such a platform as hard as possible. On the bright side, this is actually one of the easier suggestions to implement. Superweapons are expensive and, like with bioweapons, limiting their development has historical precedence. Sure, everyone will try to cheat, but as long as they all cheat equally, it will probably work out.


According rules of war, engagement must strive to minimize injury to civilian populations to the best of their ability... this does not mean that civillians are untouched... Hiroshima... Dresden... Nagasaki... and those are the ones that the "good guys" did.

I'll get to it in a minute, but first, the Geneva conventions do expressly forbid the targeting of causalities in war (all fatalities are casualties, but not all casualties are fatalities... you can be a casualty for any reason that removes you from actively fighting... injury, capture, MIA, ect all count) and is quite specific on the survivors of vehicular causalities (i.e. the vehicle is removed from combat). You are not to engage lifeboats or individuals who are parachuting from downed aircraft (where as paratroopers, i.e. those who's mission entails jumping from perfectly working aircraft, are considered combatants fair to engage while in decent... all signatory nations issue white parachutes to aircrews who's mission does not involve intentionally jumping out of a plane to identify them as casualties rather than combatants.). With regards to lifeboats, the rules also say that if you sink an enemy vessel, you must make all reasonable efforts to rescue the survivors OR contact a nearby vessel of any nation, regardless of who they are and inform them about the survivors. The survivors cannot be used as bait if you're calling their enemy... either you fish out the POWs yourself, or you let your enemy do it, at which point they are not considered a combatant. Submarines get a special exception to this after an incident in WWI where a German U-Boat was sunk while attempting a rescue of American survivors from a ship that it had sunk and was spotted by another American ship and fired upon (the American ship unaware of the sinking and knowing that U-Boats were in the area mistook it for a surfacing U-Boat while the U-Boat, owing to its nature as a stealth craft, didn't want to broadcast a general alert to the enemy of it's location but still felt it was right thing to do to help it's victims).

Now, for the purposes of your story, we move on to Treaty of Washington shenanigans. This one is more about classifying naval vessels and cheating at classifying navel vessels (the classifications, relying on contemporary weights and displacements and gun sizes to classify ships, was loopholed in a fantastic display of loopholing. For example, Germany used weight saving techniques, smaller engines that provided more speed, and smaller hulls in general to make battleships, which it couldn't own. Japan made their cruisers with guns that would qualify it as a cruiser, but built guns that would make it a battleship that could fit into the turrets of their cruisers as well as focused on Aircraft Carriers, which were classified as experimental craft and thus, not limited by the treaty. And almost everyone would report the weights and displacement before they added armor and fuel, which often resulted in ships weighing significantly when put into active duty then when it was simply sea worthy.). Heck, the ships covered by the treaty are largely out dated, but cheating still goes on... Japan just recently introduced a "Helicopter Destroyer" that to the average person, looks like an aircraft carrier (Japan can't have those by it's own constitution) but it isn't because its a Helicopter Destroyer. The United States officially operates only 11 Carriers (All of their Super-Carriers... the two terms are interchangeable in the United States). Those 20 other smaller ships that America has that look like Aircraft Carriers? Those aren't Aircraft carriers, ya silly,... those are are Amphibious Attack Ships.

Anyway, that little rant about cheating over, the point of the examples is to go to the extreme length the nations of the world go to to twist naval definitions of what ships are called. Any treaty classifying habitable space stations would likely have some very tortured justification to say they are civilian ships for the purposes of various Geneva Conventions, especially with regard to evacuation and targeting. The reason why the Geneva convention doesn't get dropped when no one is looking is that if you do things like save the surviving life boats, your enemy won't do the same to you... or worse... if you fire on an enemy while they are saving their own after you called in the survivors, then you really shouldn't be surprised when you come under fire while trying the same trick again.

The thing holding the Treaty of Washington in place is no one is going to challenge violations because they're doing the same exact thing.


As noted, the conditions to create accords can come from a shocking event (the founding of the Red Cross and the creation of the various Hague and Geneva accords came from this), but the creation of a space going civilization will likely be a continuation of existing civilizations. Most nations on Earth today which have the ability or potential to go into space are all signatories of the various Geneva Conventions and adhere (in principle) to the Laws Of Armed Conflict (LOAC), so daughter civilizations in space will also adhere to these as well.

The other driver of accepting or creating some sort of LOAC for space is the knowledge that even small objects moving at orbital or interplanetary speeds pack an enormous amount of kinetic energy. The NASA Space Shuttle had to replace the heavily armoured front windows on the flight deck because they were hit by a fleck of paint, and both the Space Shuttle and the ISS were/are monitored by ground control to track larger pieces of debris and give the crew warning to either make an orbital manoeuvre out of the way or batten down the hatches if anything larger than a screw or loose bolt approaches a certain distance from their orbital track.

enter image description here

non weapons grade damage from a paint chip

Scale this up to a full sized spacecraft and even something as small as a SpaceX Dragon capsule has the energy approaching the yield of a MOAB or small nuclear weapon(depending on its speed). One popular shorthand in SF circles is to calculate the amount of energy in a moving spacecraft in "Ricks"

The basic metric of kinetic weapons is that anything hitting you at 3 km/s - a rock, a throw pillow, whatever - delivers 4.5 megajoules of kinetic energy per kg of mass. For comparison, TNT delivers about 4.2 megajoules, meaning that at impact speeds much above 3 km/s a conventional explosive warhead merely adds insult to injury. And kinetic energy goes up with the square of velocity, so an impactor hitting at 100 km/s delivers a whallop equal to about 1000 times its mass in TNT. This is Robinson's First Law, and someone at SFConsim-l duly coined the 'Rick' as a measure of kinetic punch. As a rough and ready measure, Ricks = (Vi / 3)^2, where Vi is impact velocity.

enter image description here

The Dragon has a dry mass of 4200kg, and can carry 3310kg of cargo. Do the math....

So even routine space operations have a high level of risk associated with them.

Between this and the rather extravagant expense of military spacecraft (mounting high energy drives, high energy lasers, railguns, missile bays and multiple sensor suites similar to the Hubble Space Telescope), and it may be quite possible that there won't be an astromilitary the way commonly depicted in movies and television. No one wants to risk accidental or deliberate destruction of their habitat, and no one wants to spend the equivalent cost of an American aircraft carrier for each and every military spacecraft.

enter image description here

3 man crew and only 4 missile pods: $4.5 billion/each

Military forces may enforce political decisions through other means, such as hacking enemy systems with spyware and ransomware, conducting economic warfare (imagine day traders in uniform) and even infiltrating assassins or SoF units disguised as tourists, traders, business people or academics to carry out low level sabotage or assassinations. The prize is reducing the economic and political influence of the enemy polity, or even being able to physically seize the entire structure and its resources intact and adding it to your own store of wealth and resources.

So the built in hazards of the Space environment may serve to create conditions where no one is going to risk physical destruction by threatening physical destruction on others. Anyone who does step outside the boundaries can be pulverized by repurposed spacecraft impacting the habitat at high speeds, no need for a space battleship.

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    $\begingroup$ I suspect that's an optimistic view. When Nobel invented dynamite, he said it would end war because it was of such awesome destructiveness that no one would dare fight a war when such weapons existed. But of course today countries throw around much bigger explosives than Nobel ever dreamed of. Maybe every spacecraft would be comparable in cost to an aircraft carrier. But in World War 2 a number of countries built aircraft carriers and were not afraid to risk losing them in combat. $\endgroup$ – Jay Aug 8 '17 at 19:43
  • $\begingroup$ Both points are true, but we are now looking at orders of magnitude differences. A paint fleck could become a deadly weapon simply through virtue of its kinetic energy, while a small polity like an asteroid will not have the economic resources to build out aircraft carrier priced forces (or at best might only be able to afford one). $\endgroup$ – Thucydides Aug 9 '17 at 0:23
  • $\begingroup$ Sure. But my point was, the cost of war, in both property and human lives, has been increasing for centuries as weapons have become more destructive, but we have yet to reach the point where all human beings universally recoiled in horror and abandoned war. I think speculation that another increase in such cost will lead to such a moral revolution is unwarranted. It might happen, but I wouldn't bet the farm on it. $\endgroup$ – Jay Aug 16 '17 at 14:19
  • $\begingroup$ And need I add? If two groups both want war, presumably they have a war. If they both want peace, presumably they have peace. If one wants war and the other wants peace, they have war. You can force someone into a war by sending troops across the border. You can't force someone to make peace by sending diplomats across the border. The point being: if 90% of humanity says they want to end war but 10% decide they want to fight another war, the 10% win. $\endgroup$ – Jay Aug 16 '17 at 14:20
  • $\begingroup$ If you re read the second to last paragraph in the answer, you'll see some of the alternatives to sending multi billion dollar gunships to fight your wars. $\endgroup$ – Thucydides Aug 16 '17 at 16:13

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