I'll make this brief, cause I don't want to entirely spoil everything I have in mind.
This story came to mind while playing Carrier Command 2; specifically in regards to heavy use of AI and drone based colonization.
The background of this story is that humanity recklessly sent out automated "jump" ships by their hundreds to set up equally automated colonies that would sent resources back to habited space, be they material or agricultural in nature.
With that in mind, the planet Equestria is on finds itself on the receiving end, with many automated facilities being deployed upon the planet's surface. It's all made worse by the fact that the colony's supervisor AI has deemed the locals, be they pony, gryphon or dragon, threats to its primary objective; the production of foodstuff and other biological goods. A mix of poor programming, cost cuts and the basic limits of AI result in it being unable to see the locals as intelligent life forms, thereby it treats them as threats to be destroyed, or worse.
Respite does come to the planet, but it is only after years of warfare between the locals and the AI's rather limited self-defense measures, at least when compared to proper human military grade "blueprints". This respite comes in the form of our human protagonist, a military officer who came alone thanks to how thinly spread his interstellar nation's manpower is.
To prevent him from just stopping the conflict outright by telling the AI to cease hostilities with the locals, our Royal Sisters rip his ship from low orbit, thinking the starship was there to finish off all resistance with an orbital bombardment.
With the protagonist now vulnerable, armed with nothing but a laser pistol, basic body armor and his wits, he has to make his way to the closest colonial facility so he can assume control of the situation, once again unable to do it remotely due to an unknown interference that makes wireless beyond a few feet utterly useless, which runs the risk of the automated defenses mistaking him for a threat as they cannot pick up his IFF data.

Better yet, instead of a marine, it's a computer programmer sent to reprogram the machines and a lawyer to negotiate mineral rights. As outlined in the corporation's 'inadvertent first contact via automated mining incursion' protocol.

7553566
Well, they most certainly won't be a marine, and neither is the protagonist and wider humanity entirely aware of the situation on the planet thanks to the AI not providing the best of intelligence data. More than likely, the protag will be a naval officer; his element being in and around technology to begin w/, and his knowledge of infantry based combat not the best. Adding to this, I only plan on arming him w/ a laser pistol from the get go. However, he theoretically could impose a world wide naval blockade if given the need and ability, but that isn't his goal. Of course, there will be times where he must choose between the welfare of the locals and interests of his nation, and if it requires such a blockade, oh well...

Bluntly put; he is in command of an occupation force, but not the first or only occupation his nation is undertaking. He's not exactly from the nicest of space empires, despite not calling themselves one.

7553559
Hi.
I've always said that the plot device of "strip mining other worlds to import resources to ours" is weak, and becomes utterly ridiculous when done massively. For starters, all resources we would want to mine from space are better mined from asteroids and dwarf planets than actual planets, simply because we don't want to launch. The only thing we would ever want to do with Earth-like planets would be to colonize them, because current astronomy considers them rare.
If you want your plot devices as you explain them, say that the emerging Terran Empire sent out a terraforming drone to some very distant planet. And say that this drone was programmed by near Nazis, so it would report of "some remnants of ancient civilizations" while in reality it had gone on an extermination campaign.
Now, after a few centuries of expansion, Earth knows that terraformer drones seem to always leave these remains terribly damaged, so an archeological expedition is dispatched as soon as another report is received. And Equestria shot down their ship, fearing that the drone was receiving reinforcements.

7553941
Well yeah, the idea is that this automated colony was set up to produce the things that would be harder to replicate in a non-Earth environment; they being foodstuffs and other biological resources, but primarily the former. In this world build, humanity is recovering from another dark age, one that while shorter than the one that came before it, was far far worse; resources such as farm land and fresh water becoming exceedingly thin, and the wars that followed pretty much obliterated modern civilization.
It should come as no surprise then that the power that managed to unite what remained of Earth did so through conquest, and has no shortage of enemies. While fresh water concerns were solved by ice mining, a lack of a bountiful food supply has always plagued this empire; Earth’s soil now to beat to crap.
There’s a reason why most colonies are automated, and why the main character is being sent alone to the planet; this food shortage limits the growth rate of humanity, and things like artificial farms that can supplement such issues have only recently been rediscovered. Most of this empire’s technology is specialized in warfare; be it against small rebel groups to entire planets.
Now, there are a few other Earth-like worlds that have been colonized, but none of them have encountered intelligent life (at least, as far as anyone knows. the inhabitants of the Equestrian world may not have been the first to be the casualty of poor AI programming). Thereby, as humanity continued to expand, they started to become negligent and started to send out these automated colonies w/o much recon. As consequence, the Equestrian world has been fighting a war for survival many years before the protagonist arrives.

7554616
Okay, so Earth is becoming a Trantor or Coruscant: a hyperpopulated city-planet with so little of a functioning ecosystem that it requires nearby "garden worlds" to trade oxygen and CO2 with. Easy enough to imagine that every Lagrange point is saturated with moon sized greenhouses, and that the moon itself is being heavily mined to create more and larger spacial greenhouses in higher and higher orbits. Jupiter's and Saturn's moons are being mined for lighter elements (C, H, O, N, S, P) to be able to develop the Lagrange greenhouses, although most of its carbon needs are met by CO2 shipments from Earth. Mars is of course being slowly terraformed (and being actively bombarded with comets taken from the Kiuper Belt and Oort cloud), but it is a work of generations before it will give any returns.
Do remember, though, that this setting requires either space elevators or antigravity (low energy, non pollutant space launch systems), and an equally cheap FTL form of travel, so the idea of shipping zeppelin sized containers full of nothing but liquid oxygen isn't preposterous.

So how about this? The drone was programmed to classify the technical level of civilizations. It decided Equestria was too low level to contact, so it landed somewhere out of the way (although it had to be exactly at the equator if it was deploying a space elevator) and began mining air. And it also quickly began deploying mining drones, going for the only other things valuable enough to carry over interstellar distances: rare earth minerals, certain ores (specially bauxite (aluminium ore) for making more space zeppelins), and petroleum (which is 100% used in plastics and pharma).
Now, turns out it landed on a small archipelago claimed by Equestria but not really inhabited. A patrol finds it, the drone classifies the patrolmen as nuisance wildlife and chases them away (simply because its programmed not to let pigeons build nests).
This reaches to the Crowns, which send a scientific expedition to attempt to make contact.
The expedition fails to make contact, but determines the "sudden machine city" is extracting resources and creating nasty pollution (mainly due to leaks on the petroleum production and the extremely pollutant processes to separate rare earths).
The Crowns decide to classify the visitors as hostile, and shenanigans begin.