I’ve just started reading this set of essays - http://ndupress.ndu.edu/Portals/68/Documents/Books/spacepower.pdf, which looks really interesting ( and reminded me that I need to do much more reading on Mahan), but before I start I thought I’d write up some of my own thoughts on space power and space combat, so as to develop my thoughts more clearly before reading everyone else’s. -/possibly some stuff about changing thought patterns –/ a good book is one that changes your mind in some way.

My first assumption is that the primary weapon in space-warfare will ultimately be kinetic kill vehicles. I.e. large chunks of rock, accelerated toa a relatively high speed and put on course with the enemy. They can contain guidance systems to allow for a minor amoutn of adjustment or other secondary weapons systems for smoe reason, but their main power will be their velocity. Having a large chunk of rock smash into you at any number of kilometers per second will pretty much ruin your day.

Such weapons are also easy to make (it’s a rock), easy to use, and very difficult to defend against. Destroying the rock itself will generally not help, it’ll just break it up into smaller rocks. If this is done far enough away, then most of them will miss, or it can be nudged to a safe trajectory, but if it’s only detected when it’s close, then you are pretty much domed. Of course such a rock is damn hard to detect. It emits no energy, and will be painted unreflective black to keep it from being picked up by telescopes. It will of course occlude other objects,  but so will all manner of harmless asteroids and other space objects. You might be able to spot them at launch, so you will at leat know one is coming. But this isn’t always guaranteed - they can be launched from the whole way across the solar system, and from other stars if need be. The launches can also probably be quite easily shielded.

Because of the devastating effectiveness and ease of use of kinetic kill vehicles, anything stationary and visible is dead. This primarily means planets. In a space war planets are a deathtrap. They are highly visible. Their orbits are extremely regular and known, and they are immovable. The asteroid that killed the dinosaurs was only 10km across. It will be relatively trivial for an independent space-faring polity to capture such an asteroid and send it at Earth, or any other planet, and there is precious little defense. Ironically, this means that for the national security of any Earth nation, space expansion is practically the worst thing you can do.

So, in the opening stages of any war, all planets are dead (moons too, most likely). This isn’t actually as disastrous as it sounds, because most of humanity will probably eventually not be on planets, but in various space habitats which are much more efficient and livable than the other planets of our solar system. Conceptually, I’m using something like a O’Neill cylinder or something like it as my mental picture of a habitat, though doubtless more advanced. These habitats are much safer against kinetic kill vehicles (KKVs) than planets are. They are much smaller, and so present a smaller target. They are also movable (at least slowly).  Both sides in such a war will probably be based out of swarms of such habitats, perhaps separated by gulfs of interplanetary space, such as in a hypothetical war between cislunar habitats (after earth is destroyed) and asteroid belt habitats. A game of cat and mouse would then ensue. Both sides would try to stealth their habitats as much as possible (by painting them black, reducing energy consumption, and radiating all energy away from the enemy, and disguising them among other uninhabited objects such as actual asteroids). Both sides would train their best telescopes towards trying to spy out enemy habitats.

It is possible that an impasse would then prevail, because firing a KKV would naturally break your stealth and you would be destroyed in turn. All the more reason to build your launchers away from your habitats. But then you are faced with a similar problem: how do you get your launchers? building them during wartime will likely be spotted by the enemy and result in  a swift death. But in peacetime, everyone would be able to see you gearing up for war (unless you could pretend such launchers were actually legitimate peacetiem structures). On the other hand this could just turn into a battle of launchers, as whenever a side fires, the other side can see where they fire from, and fire one of their own KKVs at it, which reveals the positoin of that launcher, and so on until one side’s launchers are all obliterated, at which point they become defenseless.

This is not the case however if the launchers and habitats are movable quickly enough to avoid an enemy KKV strike. Depending on the launch method used, it may be possible to estimate the vctor on which the KKV was launched and manouver any assets intersecting that vector out of its path. This should be easily doable for habitats at anything other than the closest range as they persent a relatively small profile.

This could be ameliorated to some extent by adding guidance controls and thrust capability to the KKVs. This would then lead to an arms race of projectile vs installation manouverability, the outcome of which I don’t know. If KKVs win, then the situation is much as described above. If installations win, then much of the power of KKVs is diminished (except against planets), and more direct methods such as fleets would have to be utilised to attack the enemy. If the enemy are located near gravity well such as planets however, it would be possible to mount a similar attack by simply shooting large amounts of projectiles into crazy elliptical orbits around such planets to eventually saturate their space and render it extremely hazardous to any habitats stationed there. Polities not situated near any massive objects, such as those based out of asteroid belts would be relatively immune to this strategy.

In any sort of KKV warfare, volume would be a major advantage, because dispersion greatly aids survivability. Moreover, the polity covering a smaller volume has a much larger space to search than the one covering the larger volume. Because of this “exterior lines” would actually become an advantage and highly dispersed but large polities, such as could be found in the kuiper belt or oort cloud would have enormous advantages against any inner-system enemy

It is  also possible that surprise aggression would be devastating and total. In peacetime, the precise orbit and locations of all enemy habitats is easily observable. If a mass KKV attack, targeted on every one of their habitats and planets could be launched at once. If this attack could be launched secretly, then it could wipe out the majority of an enemy in the first wave of attack, leaving the rest defenceless against a mop up fleet.

This knowledge of habitat orbits would generally make a KKV war much more devastating. I imagine that at the start of hostilities all habitats would immediately start to make large burns to randomise their orbits before going into stealth mode. However these burns would be visible to the  enemy, and could be used to predict with some accuracy what the resulting orbit would be. This means that infrastructure known in peacetime (probably tehvast majority of it), would be extremely hard to hide. As such, polities with “hidden” or “secret” habitats would gain a huge advantage. As space is so visible, constructing suchhabitats would be difficult, at least for polities in the inner system. Here, once again, outer system polities gain huge advantages. It is easy to imagine military strategists in the inner system failing to keep track of all the developments going on in the sparse and less developed oort clouds, especially if self-sufficiency is greater there and trade is less, so there is less of a need for well known orbits of habitats. Once again, less “developed” regions wouldhave an advantage over more developed, clustered, and stationary polities. In general, it is easy to imagine relatively “nomadic” “barbarian” polities  widely dispersed at the edges of the solar system having enormous possible threat leverage over the greatly clustered and vulnerable, but rich, inner system polities, and consequently extracting some form of “tribute”, perhaps in the form of energy, which would be ample in the form of solar close to the sun, but incredibly paltry that far out.

As a general consequence of this, due to its dispersion and enormous volume I would suspect that the Oort cloud would have great strategic value, if not so much material value. It would certainly be the prime goal of any aliens attempting an interstellar conquest of our solar system as, from their bases in the Oort cloud they could bombard inner-system habitats with relative impunity. As such an important part of humanity’s security would be based around monitoring and securing the huge expanse of the Oort cloud.

You will note that the wars I have been considering so far have all been wars of annihilation. The aim isn’t conquest of the enemy (but keeping their citizens alive and their infrastructure intact), but rather of utter destruction and of genocide. There is a reason for that. Genocidal wars are (comparatively) easy in space. Limited wars are much more difficult.

Consider, instead of simply sitting back in your bases and launching KKVs at enemy positions, instead you need to actually project power directly into your enemy’s space. That means you need a fleet. This fleet likely cannot launch in secret - the burns required would be visible across the solar system. Once underway the fleets attack vector is fixed. This means it can be intercepted and destroyed in combat by enemy KKVs, or, similarly, by scattering dust, pebbles, and other debris along its attack vector. This can be avoided by constand manouvers, but thsi wastes valuable fuel and time, as well as broadcasting the current location of the fleet to the enemy. If the fleet is launched in secret, ten it certainly cannot be decellerated in secret. And during the whole decelleration the fleet will be exceptionally vulnerable.

One possibility is not to decellerate. Whip through on a first pass and destroy anything hostile, then decellerate and turn around and come back for the occupation. This is an answer, but it still has many vulnerabilities. For instance, what if not everything hostile was completely destroyed. Then the fleet is still vulnerable in the decellerate and turn around phase. “Destroy anything hostile” also edges perilously close to the war of annihilation, which using the fleet was intended to avoid.

Because it is so much easier to fight a genocidal war than a limited one,  any war that starts will tend to be pushed towards its genocidal limit, even if it didn’t start that way initially. As Clausewitz points out, war is a series of reciprocal actions, each tending to the extreme limit. It can be constrained by political factors; indeed war is the continuation of politics by other means, but war also has inherent military factors that shape its conduct, and the political outcome. Once unleashed, war is a beast of its own, with its own imperatives. And in space I suspect those imperatives will tend towards the total, and genocidal. Given the potential efficacy of surprise attacks, leaving a wounded and revancihst enemy around is extremely dangerous.For the same reason, you will want to do anything to maximise the power of your first strike, and that concerns about collateral damage run up against this objective.

The picture I have painted has been exceedingly bleak. In reality, however, I think a space-war like the one I described would be incredibly unlikely to break out. A simple reason is that space is huge. Our solar system alone is unimaginably vast, and stupdendously rich in the materials needed to support life. Even a humanity which can sustain exponential growth won’t exhaust these resources for another few centuries. Resource pressures in space will be relatively tiny compared to on Earth. So will “international” tensions. If you don’t like your neighhbours, sail away. If you need more resources, colonisation and utilisation of existing materials will almost always be more productive than war. Besides that, because space war will be so destructive to both sides (unless a totally efficient secret first strike is carried out), then a situation of MAD will likely prevail between hostile polities. This obviously isn’t the ideal situation, but it kept the peace for the entire cold war on earth. Arguably we got lucky, and if not for the actoins of a few men like Vasili Arkhipov at crucial points we may have descended into nuclear war. This kind of situation may happen in space too. It is easy to imagine a “launcher crisis” or some such which spirals into war. This, I suspect would be the main danger.

Another reason I suspect total wars to be unlikely is that I suspect space generally will become extremely decentralised politically. Due to the vast distances, time delays, and difficulty in conquest without absolute destruction, I suspect that most habitats will have a large degree of autonomy, if not total independence. (This assumes they could be made generally self-supporting and not require constant shipments from Earth. This won’t be the case initially, but certainly will after decades of a consistent space presence). They will be able to form loose polities and coalitions. They may also retain cultural and status links to their founding polity - either another habitat or an earth nation, but by and by large they will be independent. The result will be a bizarre welter of what are effectively, in earth terms, city states. The kind of strong, centralised, imperial state necessary to pursue a total war will not develop.

I think at this point it’s worth writing out how I foresee space development progressing, as it is one of the main assumptions of everything written above. The first is that the main focus of colonisation will be through habitats and not planets. I agree with O’Neill here (see my high frontier review). Planets are a boondoggle. The enormous cost of, for instance, rapidly terraforming Mars, is probably not worth it in the forseeable future. The most people will probably do is seed the surface with microbes and come back in a few hundred years.

The next is that space colonisation will only take off when it is economically self-sustaining. This means that space colonies must produce something, which can initially be sold at earth, and for a reasonable cost. They must also be able to maintain their own operations with minimal expensive inputs from earth. The general path I see is as follows. First the cost of reaching orbit from Earth must be brought down significantly. This might be able to be done with reusable rockets, such as what SpaceX promises, or it could be done with more exotic technologies such as surface railguns or space elevators. Once this is achieved, small habitats are built and maintained at various points such as LEO (i.e. the ISS), then the Earth-moon Lagrange point, as well as perhaps  a base on the moon. These would form the hub for all later activities. After a huge initial cost, and many years these space outputs will eventually become self-sustaining, and then profitable. Likely they will do this through a combintion of producing solar power to beam to earth, cmoplex technology which  can best/only be manufactured in space, as well as mining the moon and other asteroids for raw materials. Once this is achieved then further habitats can be assembled in situ. Those habitats will then become self-sustaining and eventually produce their own additional habitats, and so on, and humanity will begin its life as a space-faring species, eventually spreading throughout most of the solar system and perhaps beyond.

Generally, I think from this I can conclude a few things. The first is that height matters. In a gravity well, a force higher up will generally have more options, and win out over one that is lower down, assuming ruoght equivalence. A force at LEO could be used to dominate Earth’s surface. On at GEO could dominate one at LEO, a polity on the moon could, eventually, dominate those on Earth. The strategic imperative for height, then, will probably be a driver for initial expansion even though it will eventually rebound on Earth nations as their initial colonies will begin to grow in strength and demand autonomy.

Next is that in a total KKV war, the main factors for survivable are manouverability and stealth. Planets fail both of these characteristics and are consequently death traps. This is unfortunate, but not a huge problem, asby the time an actual space war occurs, most of the human population will probably be on the safer habitats. Additionally, if Earth policy-makers are smart and forward thinking (a big if, but possible) they have immense power to shape the initial norms of space towards peaceful coexistence. This is strongly in their future self interest as the Earth will probably be the bigest loser in any conflict.

Next because of stealth and manouverability, volume is also a large advantage. Larger volumes are harder to attack and easier to attack from. As such, in KKV warfare wecould expect outer-system, more dispersed civilisations to have an advantage over the more clustered inner system polities. On the other hand, we expect the inner system polities to be significantly richer, thus perhaps allowing this disadvantage to be equalised.

Lastly, because total wars of genocide are so singnificantly easier than limited wars of conquest, I expect the former to predominate, and the latter to tendto morph into the former over time. This means that avoiding war in space is extremely important. And setting up a general culture of peaceful cooperation and use of space now is vital. The good thing is that there are relatively few reasons to fight a war in space in the near future, as the resource bounty of our solar system is vast. There is more than enough for everyone, at least for the next few centuries.

The final question is, will any of this happen? Will anything I’ve written be relevant. The answer is probably not. Futurism is very hard, especially over timescales like this, and I’m nowhere near an expect. I probably can’t even imagine the new technologies and imperatives that will shape the lives and strategies of space-colonies in a few centuries time. Imagine the problem of somebody in 1700 trying to predict the strategic situation in the year 2000. I don’t know if anybody tried that, but I imagine they weren’t very successful if they did. I face a similar problem but worse: technology growth is increasing exponentially.

The big wildcard I can see is AI technology. Here I have implicitly assumed that most of the real thinking will be done by humans. Habitats will be populated by humans. And the motives of all the players will be human players. Such a futuer requires AI technology to remain relatively stagnant over the next few centuries. At least stagnant enough that we never create a superintelligence and never undergo any form of singularity. This seems unlikely, especially given the extremely rapid recent progress in AI. Most likely a future like this will never crop up. We will develop a superintelligence before we ever seriously expand our space capabilities, and what happens then is inherently unknowable.