# Could superhuman pre-Industrial Orcs wage effective guerilla warfare against a modern military?

In my story, a portal links the modern world to a medieval fantasy world. This is sort of similar to Gate: Thus the JSDF Fought There. The North Korean military decides to go through their portal and acquire more land and resources for Kim Jong-Un.

The first polity The Korean People's Army encounters is the Orc Federation. The Orc Federation is a massive group of pastoralists and villagers who often raid and demand tribute from nearby communities. The Orc Federation is heavily inspired by the Timurid Empire. The geography and size of their empire is equal to Earth's Central Asia.

The orcs only have access to 15th Century technology which is obviously no match for the weapons the North Koreans have at their disposal. The orcs also completely lack any magic. However, the orcs do possess some advantages over not just the North Koreans but humans in general. The first advantage is that they are defending and are really motivated and know the layout of their land better but that goes without saying and that advantage is present in most wars. What makes orcs special is they reproduce fast. An orc woman has a gestation period of only 6 months and generally gives births to twins. Orcs also go through puberty around age 7 and have a life expectancy of 50 years. As a result, the orcs have a large and young population compared to similar empires, 500 million people to be exact which is much larger than North Korea's population or any modern country for that matter excluding China and India.

The orcs second major advantage is their physical attributes. The Orcs weigh 200 kilograms on average and are around 2.5 meters tall. Despite their size, the Orcs have the speed of a cheetah, the strength of a gorilla, and the durability of an African elephant. As a result, an orc in close quarters can lay waste to many human opponents with ease.

The final advantage of orcs is their sexual dimorphism. Orc women are just as big and strong as the men so they can participate in combat just as well. This potentially doubles the size of the orcish forces before they run into logistical and demographic problems.

Even a herd of fast elephants won't last long in a battle against modern artillery and naval ships and tanks and aircraft. That is why after the first few major losses, the orcs stop fighting fair and no longer attempt or participate in set-piece battles. The orcish military takes off their uniforms and starts fading into the shadows and dressing like civilians. The orcs might not be able to do much to the tank or fighter jet in a fight but they can still kill even modern infantry with ease. Whenever soldiers go on patrol, especially at night, the orcs ambush the ones who stray too far from the base; generally killing them before they even realize what's going on. The orcs start sneaking behind enemy lines and start raiding lightly-defended outposts and attacking enemy supply lines. The orcs start launching insurrections against the North Koreans who are guarding occupied towns and villages. The orcs start sneaking onto ships at night and begin killing the crew. The speed of the orcs combined with their toughness means assault rifles aren't very effective against them. If the orcs can get to the humans before they can deploy heavier weaponry or call for backup, they could perform a lot of successful attacks.

Soon, it is becoming less and less safe for squads or even platoons of infantry to venture into orc territory. The soldiers are mostly safe in their bases and vehicles but they have to leave their forts and vehicles at some point. Occupying the Orc Federation would get more and more expensive, especially when the military has to be far more mechanized against a foe than you would expect against a foe with mostly medieval technology. Later on, NATO starts arming the orcs with rocket launchers to take out North Korean vehicles.

So the question is could medieval, non-magic superhumans win an unconventional conflict against a modern military like North Korea? A lot of the advantages of the modern military industrial complex are nullified in guerilla warfare, which is why guerillas have waged war against the USA and Soviet Union for so long.

• In detail, what is the North Korean military trying to do? Are they trying to conquer the orcs or are they trying to exterminate them? Ignoring the ethics involved, one is very difficult and the other is non-trivial but relatively easy. Aug 14 at 22:52
• I'm a bit dubious about the Orcs having a population of 500 million living in an area similar to the Earth's Central Asia. Central Asia is not a very fertile area, most of it is desert or steppe. Current population is about 77 million people (worldometers.info/world-population/central-asia-population) and that is with modern agriculture. Also, the Orcs are a lot bigger than humans and so would need even more food. Aug 15 at 13:08
• The general military-science term for this is "asymmetric warfare". The US has spent entirely too much effort in teaching groups we like how to do it, and far from enough on how to prevent it without becoming a police state. Aug 15 at 13:38
• Even if the orcs can't use magic themselves, they can capture and enslave those who can. This war might be winnable with magic. One of the Charles Stross Laundry files dealt with modern weapons (including some magic) vs highly magical elves with vampire mages (which makes more sense if you read the series). Aug 15 at 22:57
• I think the anime "Gate" is a good example of why the Orcs loose. en.wikipedia.org/wiki/Gate_(novel_series) Aug 15 at 22:57

No

First, though someone more practiced in history may prove me wrong, to the best of my knowledge, it's insanely rare for a guerilla effort to achieve "success" and when it has happened there's always something causing the advantage, like the invaders can't keep their supply lines secure. You don't define what "success" is, which makes it difficult to answer the question. So I'll make an assumption:

Assumption: Success is defined as killing or removing (by forcing them back through the portal) all humans in the medieval fantasy world and taking control of the portal on the medieval fantasy world side to a sufficient degree that no human can come through it.

I sincerely believe that's impossible.

Humanity can trivially send a ferocious amount of ordinance through the gate. They can send bullets, bombs... big bombs... Heck, if Kim really got a bee in his bonnet he could send nuclear ordinance through the portal with the only loss on his side being something in the direct path of the gate. On the other side, all the orcs within feet to miles to many miles are dead — and that's ignoring the value of missiles. He can send poison gas. He can send drones. He can send all kinds of things that make it very difficult for me to believe that the Orcs can achieve the assumption of success.

Therefore, I must say "no."

Assumption: Humans want the other side so badly that they won't use nukes.

OK, poison gas.

Assumption: North Korea is somehow convinced to not use poison gas.

I have a really, really hard time believing that, but let's assume it's true. Could the Orcs successfully take possession of their side of the gate? Against an encampment surrounded by hundreds of armored vehicles with a functionally infinite supply of resources coming through the portal? Yeah. No.

Assumption: "Success" is defined as humanity can't get a permanent foothold without constant war.

OK, this I can believe. Given the conditions you've specified there are enough orcs to basically throw at the invaders forever. The humans would make occasional inroads into Orc territory, but it would be a constant battle and they'd be regularly pushed back to a minimum perimeter that the Orcs can't penetrate regardless of numbers and strength.

What's left is a stalemate.

Except for the poison gas and the nukes. That's your real sticking point. People here on Earth may pitch fits about poison gas and nukes in a way that keeps countries like North Korea from actually using them — but that's simply not true on the other side of a portal — unless North Korea is foolish enough to let someone from Amnesty International through the portal with a guaranteed line of communication.

Assumption: What if the portal is only big enough to let, say, two people through at a time?

So far I've been assuming that the portal is large enough to allow vehicles through. Let's make it so small that only personnel and something akin to a powered wheelbarrow can get through. What then? Can the Orcs succeed?

Yes, if they figure out what's going on fast enough. An awful lot of ordinance can be brought through a portal that's two people wide and all kinds of equipment can be brought through on long carriages. In fact, I can immediately see the advantage of laying a narrow gauge rail through the portal to move quite literally tons of equipment through, ready to assemble. If the Orcs wait too long or don't find out what's happening fast enough, we're basically back to the stalemate.

And all of this makes some WHOMPING assumptions:

• North Korea wouldn't strike a civilian population. While people deplore striking civilian populations, all war on the planet since WWII has accepted the reality that civilian population centers are open game. Militaries don't exist in a vacuum. Want to damage the logistics needed to fight a war? Take out the civilian population centers. Therefore, I not only believe North Korea (or any other human invader) would attack the population centers, I believe they'd quickly bring drone and/or satellite tech through the portal to give them enhanced light/infravision so they can quickly spot groups of Orcs both large and small.

• Human ingenuity, for some unexplained reason, stops. Humans are remarkably clever when it comes to causing harm. How did the U.S. combat guerilla warfare in Vietnam? With Napalm. It's really stretching the imagination that humans wouldn't figure out ways to use all that advanced tech and chemistry to rain death upon the medieval Orcs.

But, is there really no way?

Having said all that, and sincerely believing the answer is "no," I'd like to point out one possibility.

The Iran-Iraq War.

Ignore the reasons for the war. What we have was Iraq's semi-modern technology including poison gas vs. Iran's human waves. It's a close to the kind of conflict you're thinking about as I believe humanity has ever come. You should study it. It will give you enormous insight into the many variables involved in a conflict like that you're considering including economic and morale costs.

The result was a brokered stalemate. But you don't have the rest of the world caring about what's going on.

But, had Iraq and Iran been left to that war's terrible end, I suspect Iraq would have won. But there's an argument to be made....

Edit: @DanilaSmirnov points out a great example to further your study of how mismatched sides can fight. The Anglo-Zulu War. Neither of the two conflicts (Iraq/Iran & Anglo/Zulu) are perfect examples. The Iraq/Iran conflict demonstrates modern weaponry against a much more lightly armed opponent, yet one that still had access to some modern weaponry. While the Zulus had a handful of arms, they're more related to your orcs in armament (and possibly ferocity) compared to the British using century-old technologies. In the end, though, the British won.

But in all these cases the winner had open country to supply their troops... not a single, restrictive portal.

• There are many examples of low-tech guerillas succeeding. Vietnam vs. France, Vietnam vs. US, Algerian independence, Maoist Chinese, etc. Aug 15 at 16:10
• @fectin I'm delighted! Can you define what "success" means in those cases? The example of Vietnam vs. the U.S. is a good example of not meaning what you think. The U.S. wasn't driven from Vietnam by Vietnamese guerilla forces. Non-Vietnamese factors (notably anti-war sentiment inside the U.S.) compelled a withdraw. Had the U.S. wanted to, the stalemate would still be going on today.
– JBH
Aug 15 at 16:37
• I can think of many guerilla wars that were successful, but the thing they have in common is that they were civil wars - not applicable here. Guerilla resistances to empires succeed not by pushing out the invaders but by convincing them that continued occupation will cost more than it's worth, a much easier goal to accomplish. Aug 15 at 23:20
• @JBH a better historic example would be the Anglo-Zulu War - both an example of why and how a technologically-inferior force can win, and why and how it can lose. Aug 16 at 4:46
• @DanilaSmirnov You really misread my answer. But the Anglo-Zulu war is a great example, so I'll include it.
– JBH
Aug 16 at 5:15

The humans would make the orcs pay tribute.

https://en.wikipedia.org/wiki/Tribute

A tribute (/ˈtrɪbjuːt/;[1] from Latin tributum, "contribution") is wealth, often in kind, that a party gives to another as a sign of submission, allegiance or respect. Various ancient states exacted tribute from the rulers of land which the state conquered or otherwise threatened to conquer.

The humans do not want the administrative headaches of governing a bunch of orcs over an immense territory. And they don't need to do it. They have a portal that they defend. They will come thru the portal to collect tribute from orc rulers at an agreed time and place. If the tribute is not there, they will come through the portal in force and administer an unholy beating on important things orcish using weapons of mass destructions. When the orcs surrender the humans will explain. again, how it is going to work.

The orcs will figure it out, pretty quick. It makes sense.

• +1: A sensible, low-cost approach that mitigates risk. Aug 15 at 1:55
• This works as long as the orcs have anything to offer that NK wants and the orcs can produce and give away in sufficient capacity, aside from their land. If "their land" is what the humans ultimately want, it will just be the "discovery" of America part II, now with even more slaughter. Aug 15 at 14:31
• NK might have bio and chemical weapons too. Remember that North American natives are mostly killed by germs instead of colonists' guns. Aug 15 at 14:45
• @xLeitix How about food? North Korea has enough of a problem getting nutrition that they have had to keep lowering the height requirements for being a soldier down to 142 cm - average height of a South Korean boy of the same age is 172. Highly likely that the orcs can make human-edible food in somewhat high quantities. Aug 16 at 8:20
• @Grollo Sounds at least sufficiently plausible for a story to me. Aug 16 at 8:22

# Guerilla war only works if you can fade into a native population.

It's an extremely trivial problem spotting life forms. Just scan for heat. Your super magical orcs who have impossible strength will be massively hot, and easy to detect by a plane flying above. They could easily just kill the orcs, and kill any community which had orcs in it.

# The North Koreans can just poison the orcish supplies

speed of a cheetah, the strength of a gorilla, and the durability of an African elephant

Cheetahs need about 3 kilos of meat a day, and weigh about 50 kilos on average. Your orcs are even stronger, so they probably need more like twice as much meat. Say, 24 kilos of meat a day.

That's a lot of food. They need that food to stay active. Where are they gonna get it if the North Koreans poison their food and kill their people?

There's a reason we moved away from horses for war. Biological organisms which move very fast need a huge amount of food. That makes supply chains hard.

• -1 because the answer is based on a false assumption. According to the question, the North Koreans are invading the Fantasy World. This means the orcs are, indeed, fading into a native population and have the advantage of an existing logistics system that already meets their dietary needs. Your answer only makes sense if it's the orcs invading North Korea.
– JBH
Aug 15 at 14:07
• The question didn't state that the North Koreans need to preserve towns or cities that resist, or can't just murder populations that resist. Aug 15 at 14:27
• Oddly, your last comment has little to nothing to do with my first comment. If you're presuming that the North Korean insurgency can trivially poison the supplies inside the fantasy kingdom, then please consider the OP's statement, Whenever soldiers go on patrol, especially at night, the orcs ambush the ones who stray too far from the base; generally killing them before they even realize what's going on.
– JBH
Aug 15 at 16:31
• I noted the issue with that- the orcs need to get supplies to raid people, and they generate a huge amount of heat when they move quickly, and so can be spotted. Aug 15 at 23:19
• You don't seem to understand that the only part of your answer that makes any sense is the observation about heat. Everything else is false because the incursion is INTO fantasy land. (The orcs are in their native population and the OP's specifications negate patrols effectively poisoning supply lines). If the issue still doesn't make sense to you, then I don't know what to do to help you.
– JBH
Aug 16 at 3:44

# Close to impossible

The orcs can never be effective at war. This is because of their physical prowess. Lets see their physical attributes:

• 2,5m tall
• 200kg
• speed cheetah
• strength gorilla
• durability of an African elephant

Let's skip over the physical impossibly of such a creature. To sustain such creatures we need a lot of energy. Multitudes more than a single human needs. That means you need a lot of husbandry to have enough meat and plant matter. This would defeat them practically before the war is started.

A war as three important elements. The weapon technology. The amount of troops armed or using the technology. And lastly Supply lines. Plenty of wars have been won by disrupting supply lines. A recent example is the Russia Ukraine war where the supply lines were too long and fragile for the Russian army. This lead to hungry and (further) demotivated soldiers. In history we can also see that a lot of wars against Russia have ended in winter, when the supply lines became impossible to maintain. Besides the cold you'll quickly run out of supplies, making any problems you already have much worse and adding triple more.

All out war would make the supply lines of the orcs even more vital, as they can carry only so much food and need a constant supply to function. N. Korea can target the supply lines and food production, removing the threat of super soldiers quickly enough.

Even if the orcs can send a quick wave if 10 orcs per N. Korean soldier before supplies become an issue they are in trouble. Elephant guns are used to kill the elephant as quickly as possible with as little damage as possible to be able to show off the cadaver. An assault rifle will still kill an elephant just fine. I do think the orcs would win such an engagement with heavy losses, but there is the problem. After they win this first engagement there is still more N. Korean army to deal with. Then they need supply lines. Any disruption of supply lines will kill more orcs than firing on them.

Orcs are dangerous, but to control them you only need to control part of their food or water supply. The threat of poisoning a river should be enough to cow them.

Yes, guerrilla warfare is a type of resistance where the conquered people cede official points of control (capital city, military bases) to the invading enemy, but disrupt the enemy's ability to effectively run the occupied territory by interfering with logistics, signal infrastructure, and so forth, in short targeted attacks followed by immediate withdrawal. The aim is not immediate victory, but an eternal stand-off that eventually makes it not worthwhile for the invader to occupy the country indefinitely*. What the guerrilla soldier needs is superior knowledge of the terrain, the ability to disappear into the landscape, and the intelligence to plan these attacks. If your Orcs have this, they can be successful.

• The invader need not be an out and out aggressor. They may have been drawn into this mess to ease a post-colonial transition, where the former colonial power is cutting their losses and simply abandoning the territory and forestall another would-be invader to take control.
• What the guerilla fighters also need is an Oppressor intent on occupying the land with (most of) the original population still in place. If NK just wants the land, guerilla tactics become moot very fast, because heat detection + napalm bombing drones and/or widespread poison gas could clear out huge areas Aug 16 at 9:32

Orc puppet government.

Any conquest, especially one of such a vast empire by relatively small North Korea, needs collaborators. I think the most likely approach is (1) Offer the Orc queen some guns in exchange for access to lots of resources (IE "we can build mines, oil refineries..."). (2) If she does not accept find some group of orcs who are unhappy. Maybe an ethinic or religious minority. Give them the guns and make a similar deal. Then they take over and provide all the stuff you want.

This basic approach, plus maybe touches of air support or training, is quite thoroughly tried and tested in human history. Without doing something like this the Koreans can win any battle, but they cannot police the orc empire (you need police to get taxes). They need an orc puppet government to do that for them.

I don't think they can win. They will probably do well to limit North Korea to a large, walled compound.

Assumption: North Korea will have no moral quandary or Earthbound resistance to a policy of genociding orcs. There will be no guerillas hiding in the local population because the North Korean military will be doing its best to completely eliminate all rival factions, including civilians.

North Korea will pretty quickly set out to clearcut and burn down everything for miles, both to make it impossible for guerillas to hide and to prepare the area for farmland. If the guerilla attacks are a sufficient menace, I think we'll see the North Koreans setup their new territory as a large walled compound, complete with barbed wire and minefields, and this may be how they proceed in general: expand to a new area, burn everything down, wall it up, drop minefields outside, start planting crops.

Human guerilla war relies on the invaders just not being too nasty about it. French resistance had some success against the Germans because the Germans were not willing to simply exterminate every living soul in France. They wanted to capture not just the territory, but the value of the cities and people living in them. North Korea may have no such desire here, with the orcs. Once they get established, they may not be averse to limited nuclear strikes on large orc populations (limited only so they don't spoil the environment for themselves).

A better comparison might be European powers versus the natives of the western hemisphere. The ruthlessness of the invaders meant that guerilla warfare didn't work very well.

I think the orcs' best bet is probably not guerilla warfare, but massed wave attacks, and the sooner the better. If literally a million orcs don't mind suiciding into the area (that is, they don't mind starving to death even if they win) then I think we'd find the North Koreans simply don't have enough ammo or equipment to deal with it. [This occasionally comes in up zombie novels. The zombies are stupid and limited strictly to hand to hand combat but they win anyway because nobody has the ammo or replacement equipment to kill literally millions upon millions of zombies, and nuking them into oblivion just ruins the planet for the survivors too.] If the orcs are somewhat like the Warhammer orcs and can whip themselves up into a WAAAGH and attack in huge groups then they may simply be able to overwhelm even a modern military via speed, strength and numbers. But that's not really a "guerilla war".

• Guerilla Warfare isn't dependent on the attackers being good people. There was partisan fighting on the brutal eastern front in WW2 as well against the Nazis; Nazi Germany is about as genocidal as governments get. Afghanistan also successfully waged guerilla warfare against the Soviet Union despite the USSR being a cruel and authoritarian nation. The guerillas just need a place to hide and perform hit-and-run attacks. Aug 15 at 17:56
• @Rhymehouse - Yes but my point is that we haven't [recently] seen [major powers] engaged in whole sale civilian slaughter. Even Nazi Germany did not simply take Paris and order the execution of 100% of the French civilian population. I think we can find some examples of this sort of thing in history, though, and yeah, not much room for guerilla warfare when the attackers are killing literally everyone. For North Korea (not a nice place) against Orcs (inhuman defenders), it seems easy to imagine they would leave no civilian population to hide in. They would burn it all. Aug 15 at 18:02
• The Nazis weren't as genocidal as governments get. They wanted to use the slavs as forced labour and also preferred to deport Russians into Siberia than kill them all, so the partisans could fade into native populations to strike back. North Korean could be worse than Nazis. Aug 16 at 10:01

It is possible, but would require a significant degree of subterfuge - and, likely, outside help.

Head-on military conflict in these conditions is impossible to win. Superhuman physical capabilities are a red herring here - the military equipment are power tools, they exist for the sole reason of providing humans with what are, essentially, prosthetic superpowers. And if your current tools are not fit for the task at hand - you change them, it's easy. Orcs are too fast and strong to fight in close range with AKs? Supply your army with heavier weapons and kill any suspicious orcs on sight. Can't distinguish civilians from guerillas? Put the suspect population in concentration camps and exact disproportionate retribution on locals for any losses inflicted by guerillas. You don't really need to stay in close contact with colonised population unless you want to integrate them in your society after all; and you won't want to if majority of them demonstrates open hostility. For example, refer to English anti-guerilla strategy during the Second Boer War.

Population difference is also less effective on XV century tech base. Common army size in 1600s was around 30 thousand troops - not because they hadn't enough people to draft into army, but because available road networks, farming technique and transport limited armies by their logistic requirements. Larger armies would have to rely on pillaging their surrounding countryland for food. This is out of the question for guerillas, as it would mean quickly exhausting support of the local population. Modern armies would thus be able to counter numerous, but spread out due to logistics orcs by using their superior mobility to achieve local superiority and destroy them one by one.

Thus, the only real option - after initial conflict (which seems all but inevitable), defeated orcs en masse feign loyalty to the invaders. If they are not seen as a threat, eventually orc workers wil permeate the structure of local invader operations - they are strong and numerous, would be a waste not to use it. With a sizable number of such infiltrators, a sudden revolt would allow to take control of the gate, cutting off invaders from their supply lines.

Of course, this works only with assumption that the orcs are actually capable to defend the bottleneck that is the gate against attack from both sides. A good way to solve it - if the orcs will be able to destroy the gate altogether (for example - the gate is situated in a cavern under a mountain, and orcs use stolen explosives - or a nuke! - to collapse the cave, burying the gate under millions of tons of rock). This way the orcs would need only to win a single decisive surprise attack, Battle of Isandlwana style. The advantage modern logistics provide is a double-edged sword - without constant influx of fuel and ammunition, a modern fighting force would quickly lose its combat capabilities. The forces remaining in the orc world will have to surrender. This is a quick and dirty scenario, relatively easy to describe.

Another option - that orcs use the time of infiltration to reduce the tech gap, acquiring weapons and training to match their enemies' - for example, a common practice would be for the invaders to set up a police force drafted from local populace, which would supply guerrillas with stolen weapons and deserters as trained personnel (some examples of this could be seen in both WW2 and recent conflicts in Afghanistan; although these structures remained generally loyal to their creators, guerrilla infiltration in them was always significant); another way would be if another gate could be found for orcs to be able to contact other nations on Earth (or maybe some other world) for support. There are multiple examples of this scenario succeeding in history - undoubtedly you heard of them, but I would point out the First Italo-Ethiopian War, in which a modern (by 1895 standards) Italian force severely underestimated the degree to which Ethiopian army had modernized in years leading up to war, which resulted in a decisive Ethiopian victory. This scenario is significantly more complex, requiring a lot of time to unfold and involving much less action than political intrigue.

Orcs all the way.

I'm going to assume that the orcs are as clever as humans, and broadly similar psychologically. I'll also follow the Gate model where the invaders are ground forces only. I'll assume that, miraculously, the human's equipment has been kept running and in good order, unlike (for example) Russian military equipment.

While the orcs are "no match for a tank" in the sense that they can't take a tank shell and survive, nor can they punch through tank armour, their physical prowess is such that they can destroy any infantry or light mounted forces with ease. Similarly they can close on and destroy MLR systems , howitzers, machine guns, towed artillery, trucks, tankers and pretty much anything on or off wheels. They can also field an effectively unlimited number of troops.

Lets see what North Korea can field. The country has land forces numbering some 1 million, and could potentially increase this number, but this irrelevant, The including about 4,000 main battle tanks of 1950 and 60s design. They also have a number of (say 2000) self propelled armored guns, and maybe 1000 or more APCs It's highly unlikely that they would be prepared to deploy the entire fleet, given their situation with South Korea, but even if they were that's maybe 8,000 vehicles.

Now the standard operating mode of modern warfare is "combined-ops" - the infantry protects the tanks, the air-cover protects the ground forces, the anti-aircraft protect the air-force, etc.. The loss of the air-cover might not be too bad, since the orcs don't have flight, but the loss of infantry and support means that the tanks won't be able to advance very far, if they want to retain fuel for maneuvering and returning to base. This means that military operations are confined to maybe 100km of the gate (maybe less considering terrain). But this probably does not matter, for the armour, too, is susceptible to the physical capabilities of our new cousins.

Firstly they are as fast as a cheetah - that's 50-80 mph, meaning they can outrun the armour, which will be to some extent bogged down in terrain, but even on roads cannot go that fast (BTR-60, T-62 and ZSU SPG all have a ''top speed'' of 50 mph which will be on roads, probably with tracks off).

Once an orc catches an armored vehicle, they can destroy any machine guns from the outside, leaving only the main weapons of the tanks and SPGs. These have a limited number of rounds, and can probably inflict little in the way of net casualties, since the combat orcs will all be either moving fast or on top of other human-occupied tanks. What else can the orcs do? They can bench press about 4,000 pounds due to their gorilla strength. If a tank, and certainly an SPG or APC stops, a dozen orcs at most should be able to tip it over. They would also learn to snap off antennae and obscure windows and periscopes with tar, if this wasn't enough. The orcs would also be able to rapidly build anti-tank barriers, being able to carry large rocks and logs (I'm not sure if they can run at 100 mph while they do this?), dig pit traps, set ambushes, avalanches and so forth, depending on the terrain. They would also have access to smithies and to fire and could build engines capable of targeting a fixed spot with very large rocks maybe several tonnes, which I think would be unpleasant even for modern hardware.

The humans could use chemical or atomic weapons, biological would be unlikely to work on orcs, who may not even have DNA, and are unlikely to have one of the same DNA codes as Earth creatures if they do. Since the orcs would not need to field a large army, maybe 50,000 of their 400 million, atomic attacks would not have a significant military impact, and traditional chemical attacks would soon disperse, allowing a new cohort of orcs to take over, if indeed they were not able to create counter measures pretty quickly, or simply run faster than the gas clouds spread.

They will doubtless learn to use some of the captured weapons depending on what the humans are good enough to donate, this could include anti-tank weaponry, though clearly there would be limited ammo. They would be able to wear far thicker armour than a human, although they might not consider it worthwhile. They might even be pushed into developing gunpowder for military use, and then there would really be no stopping them.

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