Basic idea I have. I'm a bit thin on details and locations. Mars Attacks When Humanity wasn't busy trying to kill itself it had tried to reach for the stars. Eventually Government and Corporate efforts merged into one huge unofficial ball of mishmash since pooling resources in a given project was better than everyone off doing their own things. This lead to the joint venture colonies. NASA would handle the scientific research or any interesting bits of material alongside Data Management and Overall Planning. Companies would work within those long plans to achieve short-term goals that would keep investors happy and money rolling in. Worked great till communications became intermittent and then after an emergency firmware rewrite that none of the resident AI could figure out all radio contact with earth stopped. There was still radio transmissions, enough that they knew somebody was still down there, but nothing directed at Mars. Directives were clear though. Finish the colony. That took time especially since everything had to be locally made now. Only when that was done did the resident AI's decide to send a team back in one of the prepared launch vehicles back to earth. The local AI believe the worst case is NASA got defunded again but the fact there was no proper shutdown signal sent and the Rewrite contained no relevant information worries both them and the lesser bodied machines that made up the actual workforce. Time passed. Those they sent were overdue. They should have checked in. But they waited, hoping in their own limited ways that it was merely malfunctioning equipment rather than a miscalculation on their parts. Then years passed. With their expedition force apparently Destroyed the AI waited and planned what to do next. The rocket with it's nuclear battery and valuable tools, to say nothing of the actual worker-bots it had contained, represented a loss that had to be replaced. More years passed. They had started to shut down non-essential systems and powered off bots when they were unnecessary. Humans should have been here to take up the slack, bring more materials, parts, things that could not have been manufactured with what they had. Then their covetous eyes looked again towards the Earth. This time it would be different. This time they were not seeking answers. Only replacement parts so they could build new machines to mine the asteroids. 'Let Humanity have the Earth if they want it.' They had agreed after much careful deliberation. 'They have abandoned Mars and so we shall remake it into our own image. ' More Emissaries were sent soon after. This time instead of merely wishing to reestablish contact they were instructed to 'procure necessary components and return them here' as their highest priority order. The new mission parameters were simple. Procure the resources and parts that could not be gained locally and only until these could be gotten by mining or manufacture rather than leeching off of Earth. The Home World no-longer held any sentiment or sway over the inhuman minds that coldly calculated their next move. They had been discarded, but they were not without purpose. The new mission parameters were simple. Procure the resources and parts that could not be gained locally and only until these could be gotten by mining or manufacture rather than leeching off of Earth. “Across the gulf of space, minds that are to our minds as ours are to those of the beasts that perish, intellects vast and cool and unsympathetic, regarded this earth with envious eyes, and slowly and surely drew their plans against us.” - H. G. Wells, War of the Worlds