Ok, rewriting this one, so some of the answers and comments are from a simpler version:

Let's say, in an alternate timeline, or on another world, we discover the equivalent of mechanized warfare -- tanks, battleships, cruisers, police APCs, jeeps, bazookas and other anti-tank weapons, etc.

How close to our own tech, say from World War II, would it have to be to still be considered armored fighting vehicles? How different could they be and still be considered AFVs?

What technologies would the race be expected to have mastered BEFORE inventing alien tanks and battleships? It doesn't have to follow our own history, but there must be some parallels. What sort of history would they have had to get to a point where they NEEDED to invent such vehicles? On Earth, we had trench warfare which drove the invention of tanks. Could tanks be invented WITHOUT trench warfare? Why? What materials would be necessary to build them -- could a planet low in iron use something other than steel to protect them? Could a world without the elements of gunpowder still build something to penetrate that armor? Why would the society go to all that work to build a lot of heavy vehicles armed and defended to fight with in the first place? Are treads a necessity or could something else be used? Do you have to have an internal combustion engine or could steam or something else work?

I guess I should have worded the whole thing differently. I'm basically trying to figure out, in a different timeline or on a different planet, what would the requirements for a race be to develop armored warfare. A race that didn't use metal or were pacifists or didn't discover gunpowder or didn't have fossil fuels to power an internal engine probably wouldn't invent it, so I'm trying to figure out what they WOULD be like. I don't know, maybe you could build tanks and battleships without metal or gunpowder or fossil fuels, but at what point would we no longer recognize them as armored war vehicles but as something else? In short, I'm trying to apply Civilization's tech tree to a culture other than our own history.

Original post:

Let's say we come across an alien world. Scans show they have yet to develop atomic weapons or energy. The first images come back from the surface, and they show a group of metal vehicles with what appears to be some sort of gun or cannon barrel on them. These beings are using a variation of armored fighting vehicles.

What could one extrapolate about their culture based solely on this information? A few guesses:

  1. They have some sort of industry to be able to produce multiple vehicles.
  2. They have metallurgy to create the thick armor, and the metals in their crust to produce them.
  3. They have some sort of propulsion to move these ground vehicles without rails.
  4. They have some sort of projectile technology powerful enough to penetrate thick armor.
  5. They are engaged in some sort of significant conflict that would justify building these machines.

Anything more specific or general that one could surmise about their personalities, their technology, their civilization?

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    $\begingroup$ ...or this is a fire engine. $\endgroup$ Commented Sep 18, 2023 at 18:48
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    $\begingroup$ Unless the photographic cameras has superpowers, you cannot tell from a photograph if the vehicle is made of metal or cardboard. And you definitely cannot tell if it is armored or not, or how thick the armor is. But one thing you can tell, and the question does not say, is whether the vehicles have wheels of caterpillar tracks; that is a very important thing to know. $\endgroup$
    – AlexP
    Commented Sep 18, 2023 at 18:59
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    $\begingroup$ There are a lot of great questions in your list of example points. Consider posting these as distinct questions. $\endgroup$
    – Atog
    Commented Sep 19, 2023 at 4:05
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    $\begingroup$ I know that all your sub-questions fall more or less in the general question "What can we extrapolate from sering armored vehicles", but here there are too many with many different sub-themes. This strongly hints you're not asking about specific problem about meeting your alien as it is required here. Try to get your alien creature in top shape, then ask us to solve the troubles you met midway ☺️. This will give the answers much more value than right now. $\endgroup$ Commented Sep 19, 2023 at 7:05
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    $\begingroup$ On WorldBuilder.SE, you are not supposed to rewrite a question to the degree that it invalidates existing answers. Please revert the question to its original form, and ask this as a separate question. $\endgroup$
    – Nosajimiki
    Commented Sep 19, 2023 at 13:11

7 Answers 7


Very little actually

The first images come back from the surface, and they show a group of metal vehicles with what appears to be some sort of gun or cannon barrel on them.

Without knowing more about the alien civilization, you aerial/orbital imagery can not really confirm that you are looking at an armored fighting vehicle at all. You may see something that resembles an armored fighting vehicle, but unless you actually see it engage in combat, it could be anything: farm equipment, a wetlands construction vehicle, a directional drilling vehicle, a truck with a light duty crane on it, a mobile observatory... you really have no idea.

If these are in fact your 1st photos, then they alone are not even proof that they are an industrial society. What looks like a tank may in fact just be an unhitched wagon with some curiously shaped stuff strapped on top, and the metallicness could be a simple trick of the paint job or the "wood" on thier planet just so happens to be shinny. That said, real tanks do not appear metallic anyway because they are painted to not be shinny; so, appearing metallic is itself suspicious.

Now don't get me wrong, the news will be abuzz with click-bait headlines that read "Alien tanks photographed, and they are coming for Earth!" ... but all of your your actual arial surveillance specialists will likely shoot down any hasty conclusions about what they are looking at on the grounds that we do not yet have a baseline record of what we are looking at with this particular alien's technology.

enter image description here

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    $\begingroup$ Oh! No, it's a tank being drawn by two horses! $\endgroup$
    – elemtilas
    Commented Sep 19, 2023 at 15:09
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    $\begingroup$ @elemtilas Ah you caught me, it's actually just one of these: qph.cf2.quoracdn.net/… ... not really, it is actually a sleigh, but it does reinforce the possibility that it could be a wide range of things. $\endgroup$
    – Nosajimiki
    Commented Sep 19, 2023 at 15:29
  • Industry?
    Yes, but if there is industry, orbital observation should be able to tell that from the steelworks, and the rails going towards the steelworks, and the pollution in the atmosphere downwind from the steel works.
  • Engines?
    The relevant thing here is probably that the engines are not electric motors powered by a trolley system. They are self-contained.
  • Armor and weapons?
    If orbital observation can show conclusively that the barrels are projectile weapons, you could still have a doctrine where tanks fight infantry, anti-tank guns fight tanks, and infantry fights anti-tank guns (i.e. guns on tanks are not necessarily good enough to penetrate tank armor).
  • Fighting wars?
    Either that, or they value the life of their cops so much that they get APCs/IFVs.

To get more conclusive, you would have to observe an actual battle. By watching the armor in action, they might get information about:

  • The ability to work in teams as opposed to individuals. To they ever dismount squads? Do the vehicles use wingman tactics and overwatch?
  • The value they place on individuals vs. the benefit of society. Do they routinely sacrifice rear guards or feints?
  • The power-to-weight ratio of their engines.
  • Class or caste differences from the uniformity of equipment or difference. Heavies supported by mediums and lights, or standard MBTs? That could also be a mistake, if the differences are simply different roles and not different status.
  • $\begingroup$ Would steel be required, of could some other material fit the same role? Do the self-contained engines need diesel or could coal and steam work? $\endgroup$
    – Jason Holm
    Commented Sep 19, 2023 at 2:54
  • $\begingroup$ @JasonHolm, if not steel, then other industrial materials. An aluminum plant is equally visible. There were early steam tanks, but they did not have the power-to-weight ratio to allow effective armor. So you could build in surprises: the orbital observers believe that there must be internal combustion engines, and it turns out that they have highly developed external combustion engines instead. $\endgroup$
    – o.m.
    Commented Sep 19, 2023 at 4:20
  • $\begingroup$ @JasonHolm electric cars were quite commonplace very early on (when gasoline engines were bad as well), so no combustion required. Also any material that strikes a balance between affordeable, hard, malleable and light could work, ESPECIALLY if the weapon side of the civilisation is "underdeveloped", hardwood (there is insanely tough wood IRL, nevermind what could be handwaved on an alien planet), insect secretions etc. there are a lot of options beyond steel. Though the tools required to machine said armor would require something close to steel, the armor not so much $\endgroup$
    – Hobbamok
    Commented Sep 19, 2023 at 9:10
  • $\begingroup$ @Hobbamok, back then batteries could power a flimsy car on sort-of-decent roads, not a tank through shellholes and trenches. $\endgroup$
    – o.m.
    Commented Sep 19, 2023 at 14:36
  • $\begingroup$ With sufficient volcanism, could you have steelworks without burning anything, a la dwarf fortress? Yes, you still need something for carbon, but it'd be significantly less. $\endgroup$ Commented Sep 19, 2023 at 14:52

The question was heavily rewritten, so a new answer ...

  • Removing iron ore from the crust of the planet would significantly alter the chemical composition of the planet. I cannot predict how the species would look like, let alone their technology.
  • You could remove fossil fuels from the planet. With nothing better than charcoal, the industrial revolution may not happen.
  • Historically, the first tracked tanks were developed to break the stalemate of trench warfare. They were what was later called infantry tanks (heavily armored, slow, good at crossing shell holes, relatively weak armaments). Before the tank there were armored cars (less heavily armored, faster, worse at crossing shell holes, relatively weak armaments). Without a world war in the 1910s, armored cars could have developed into a kind of tracked tank that was optimized e.g. for colonial wars.
  • A cynic might argue that heavy armor is the proof of a peaceful society. The term gunpowder empire was used for states where the development of powder and cannon strengthened the central authorities. The explanation is a bit too simple to explain real history, but a society of individual, status-seeking, competing warriors will not build tanks. Tanks require factories, factories require laws. A single warlord might be able to coerce a blacksmith to forge a sword, but not a society to build the tools to build the tools to build tanks.
  • $\begingroup$ The industrial revolution could still happen, it just wouldn't go as fast. The historical industrial revolution started out with waterwheels, not steam. I'd expect a coal-free revolution to stall for a time before developing a non-fossil energy source (and it might focus on aluminum rather than steel -- coal provides more than just heat when making steel). $\endgroup$
    – Mark
    Commented Sep 20, 2023 at 3:29
  • $\begingroup$ @Mark, aluminum takes an awesome amount of energy. Coal was used from the 14th century for heating. $\endgroup$
    – o.m.
    Commented Sep 20, 2023 at 4:31
  • $\begingroup$ Aluminum takes an awesome amount of energy, but it can all be provided in the form of electricity. Steel requires coal (or some other source of bulk carbon) twice: first to carry off the oxides during smelting, and then to provide the dissolved carbon that differentiates steel from iron. $\endgroup$
    – Mark
    Commented Sep 20, 2023 at 21:47

Frame Challenge

From just a photograph, absent any of the context that would be required - extremely little.

Let's go through your presuppositions:

  • No Nuclear Energy.
    maybe - but perhaps that's because they have advanced past the need for Nuclear Energy? Maybe they have an energy source that is unknown to us.

  • They have some sort of industry to be able to produce multiple vehicles.
    Perhaps - this is probably the most reasonable assumption - but even then, I would call this into question. When you say 'industry', one is assuming factories that churn-out standardized equipment. Without being able to measure each vehicle and confirm it's dimensions, it's entirely possible that each one is built by an artisan craftsman - plenty of homebuilt (not kit) cars exist - and this would mean that the implication of 'industry' isn't entirely justified.

  • They have metallurgy to create the thick armor, and the metals in their crust to produce them.
    As others have pointed out in the comments, from a picture alone, you can't determine what a vehicle is made of. However, you could use something like an advanced MAD (Magnetic Anomaly Detection) that was sensitive enough to pick up an object the size of a Tank (they are normally used for detecting Submarines - which are bigger and therefore have a bigger magnetic footprint) - which would confirm they have metallurgy and that there is a source locally for these metals.

  • They have some sort of propulsion to move these ground vehicles without rails.
    This is perhaps the most reasonable assumption - if you see a 'vehicle' move from one photograph to the next, it's a pretty slam-dunk case, right? Well - again - what if they did have some form of Rails that we couldn't see or were unknown to us? Maybe some weird under-ground magnetic thing (I dunno why I'm thinking about Magnets so much)

  • They have some sort of projectile technology powerful enough to penetrate thick armor.
    Unless you see a round being fired and it having a downrange effect, nope - a long tube could be anything. It may not even be a weapon. They may be what you think they are, and the long tube could be a sensor array and the tiny little sticky-outy things on the hull might be the Death-ray-Zapper-3000.

  • They are engaged in some sort of significant conflict that would justify building these machines.
    As above - too many unknowns from just photographs. Chuck in some video and perhaps some other scanning tools, then potentially you could start to make the above inferences. I would still be highly cautious in anthropomorphizing humanity and our quirks onto alien cultures and lifeforms.

That said - there is a scenario where you could infer a lot of the info that you seek (and more) - which is if you captured one and were able to do a detailed inspection/analysis.

If you were to look at say The Chieftains's YouTube channel (he is an Irish American Tanker and does a lot of educational stuff on Armored warfare) - he does a series called inside the hatch, where he looks at the insides of particular fighting vehicles.

From design decisions, you can infer a lot of information - such as relative technology competency, function, industrial competency, where they place their value (Big Gun, Big Armor, Big agility?) - you could infer a lot about the anatomy of the occupants - for example, South Africa before the end of Apartheid - used to issue Service Rifles with extended butt-stocks as the Dutch settlers are taller/lankier than the average (seriously - the Dutch can be weirdly tall).

But even then - imagine you were to show someone who had never seen a human or a rifle two service rifles just on the ground - without any context, it would be difficult to infer anything about it. Once you have a little bit of Context, however, the inferences start to open up.

  • $\begingroup$ the no nuclear energy was to limit them to a similar progression in our timeline -- world war II. I know, aliens won't follow our tech tree progression, but trying to figure out when in their timeline they would invent such things that are equivalent to our own WWII machines, what other techs would be required and which ones could be skipped on taken a different way. $\endgroup$
    – Jason Holm
    Commented Sep 19, 2023 at 2:57
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    $\begingroup$ @JasonHolm - I appreciate your point - however, If we look at our own history - we have Tribes in Africa that still do not have the ability to make machines equivalent to WW2, We have for example China inventing Gun powder and the Fire lance, but it's the europeans who invent the cartridge and are able to make repeating/automatic Firearms. There is no reason to presume that an alien culture would follow a technological progression that looks anything like ours. $\endgroup$ Commented Sep 19, 2023 at 3:47

I had a little to do with satellite images in the 80's. This is a while ago, but the basic optics are the same. If you are in a high, stable orbit, there is not a lot you can see at the surface at sub-metre resolution. A vehicle is a small box. A tank is generally seen because it lies at the end of a set of tank tracks. With radar, a submarine is invisible but its wake can be imaged if it is moving steadily and the see is calm-ish.

If you can see them, they can see you too. It is probably better to send in some disposable probe and get a better look. And say 'hello' while you are at it.

PS: If this is a truly alien world, and they have evolved over billions of years, it would be surprising to catch them at this exact point of development. I would find it more likely that you are seeing their equivalent of a medieval re-enactment society than an actual tank battle.


Anything more specific or general that one could surmise about their personalities, their technology, their civilization?

Well, we can surmise that they aren't united as a planet. Else they wouldn't be fighting. From that, we can deduce that they aren't ready for contact with other species, if they fight among themselves, they fight the aliens.

Let's say we come across an alien world. Scans show they have yet to develop atomic weapons or energy.

Without energy, I can't see a way to create these monstrous THICK armored tanks, but I can see them using Lava in molds to create the armor, providing they can carve a big iron/nickel/steel boulder into a bucket, which in itself would tell you that they have tools. As for moving them, it would require some type of engine, they could have found a pocket of methane and are using it to power their tank engines.

So IMO, they would need to have the following before being able to create a tank :

  • Some kind of food production.
  • Basic medicine so they don't die to the equivalent of an infection.
  • Administration (someone in charge of getting the resources, what's needed etc.)
  • Houses to prevent them dying in their sleep
  • Enough people that some aren't needed to do manual labor
  • A reasonable population that can maintain everyone fed
  • Lack of a certain resource OR Be attacked by something

There's always the possibility of the environment (animals) being too aggressive for your aliens to face, so they transport themselves in these tanks to get protection from natural predators (we have to assume the predators have above animal intelligence).

The tank could have wheels, it all depends on the total weight, their crust could be made of some Unobtanium (made up material) that's super strong (like titanium) and super light (like aerogel), making the possibility for out of the ground transport, or not that light, and wheel transport might be okay. Weapons/Main cannon could just be a giant version of a slingshot.

Ultimately what they NEED in order to make a tank, is something BIG and SCARY, preferably that kills you.

But you can't know a lot from this, at least without proper context.


On a battlefield, you have:

  • Guys moving under their own power (infantry)
  • Guys moving with artificially increased power (vehicles)
  • Guys not moving at all (fortifications and bunkers)

Power limits both your offense (weapons) and defense (armor). With gunpowder, it's very easy to make weapons that can easily kill infantry. Armor for infantry is kind of a losing battle - you can only wear so much before you can barely move, and there are still guns that can kill you that can be carried by infantry (eg. anti material rifles will punch through any armor you can carry). Plus you're now very slow, and the very big anti-fortification ("siege") weapons can be used against you too, and no amount of armor is going to stop those.

Vehicles have engines which allows them to have almost arbitrarily more power. There are of course limits imposed by materials, engine efficiency and so on. But the point is, a vehicle can carry much stronger weapons and armor to the point were infantry (who are limited to their natural power) are hopeless against it. But it avoids the "Ned Kelly problem" because it can still move and avoid siege weapons, due to its engine.

From this you realize that the tank actually occupies an interesting niche: If it's too lightly armored (like a plain car with a turret on it) then light weapons would kill it as easily as infantry. The mobility doesn't help because infantry weapons are pretty easy to aim even at a speeding car. But if it was too armored, it would be slow, and then siege weapons (designed with stationary targets in mind and compromises to maximize power) would cut through its armor anyway. So this niche of "just enough armor, just enough speed to dominate infantry, but escape siege weapons" is a requirement for the tank to exist.

Of course, just being too strong for infantry and too fast for siege weapons is still a broad spectrum. In actuality, tanks also attack each other, so their after overcoming infantry their driving force becomes an arms race vs. other tanks but capped by siege weapons.

The above is basically a WW2 perspective on the raison d'etre of tanks if you will. You will notice that in many cases my assertions are questionable:

  • Mobility without armor or even weapons can be useful to infantry by allowing them to outmaneuver enemy infantry or even particularly aim-able siege weapons.
  • Infantry can have weapons strong enough to kill even very armored tanks, like the Javelin, which is sort of approaching "siege weapons light enough to be carried by infantry".
  • Infantry can be given exoskeletons (or even biological augmentations) that also arbitrarily increase their power, which allows them to catch up to tanks. (although arguably an exoskeleton would make them a vehicle)
  • Infantry can be removed from combat using remote control and AI (drones). This can lead to vehicles that have minimal armor and weapons but do suicide attacks (cruise missiles).

These basically did not apply in WW2, and were questionable in the Cold War, so these periods were the heyday of the tank. Today, other tech like munitions, guidance and electronics is catching up to metallurgy and propulsion, so tanks are beginning to lose relevance.

In your case, you are basically asking would some other civilization have a period similar to ours during the 20th century? Let's flip that and ask what it would take for them to not have such a period. They must not make advances in propulsion and metallurgy that outstrip the limitations of their weaponry and control systems at that time. So it's not just about requiring some set of techs, but also the relative balance between them.

Imagine if by 1940s we discovered guided missiles, high explosives and advanced fuses. But somehow vehicle engines lagged behind, and "tanks" all moved at 15 mph like in WW1. Manning such a tank would be suicide, fielding it would be a waste of resources. Or what if engines were advanced but we just couldn't make very good armor yet, and people just used the same old anti-infantry machine gun on the fast but poorly armored vehicles. Or they were armored, but slow due to poor weight/protection ratio.

Interestingly, we can recognize concepts from ancient history as analogous to tanks, like cavalry and elephants. Early doctrine even referred to tanks as cavalry. While you can't arbitrarily increase the power of an animal like with engines, riding a strong animal obviously gives you the ability to carry far more armor and bigger weapons than infantry can on their own two legs, while still having enough mobility to avoid siege weapons like catapults.

Similarly, I think that if you observe this alternate civ having "tanks" (something impervious to their "infantry" but too nimble for their heaviest weapons) then you can conclude that their propulsion and armor tech is leading and vice versa (expect a "tank" from the tech). But you can't decide if it's bronze age propulsion vs. stone age weaponry, or atomic age propulsion vs. industrial age weaponry.

Regarding battleships, they are basically the tanks of the sea. Too armored for light vehicles, too mobile for siege guns (forts). But, in WW2 weapons advanced enough that you could have pretty powerful ones on little planes or torpedo boats, that could kill even the most armored battleship. This quickly brought about the decline of the battleship, like anti-tank missiles brought the decline of the tank.


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