The Colony

[Parallax]

The second season of The Colony has just started and I thought it could be an interesting discussion, based on how the alien takeover happened.

In short,the story starts with current day Earth having been conquered by an unknown alien species and walled reasonable small colonies of humans being left to live their lives and serve the aliens - as commanded by hand picked human overseers. The first season really doesn't show HOW the invasion happened but the second season does.

Spoilers!

The aliens themselves don't seem to be anything terribly special and we don't know much about them. They gained dominance by apparently using the already made list of people who would be responsible for rebuilding society should a cataclysm happen. These experts/specialists were hired by human intermederies or simply abducted. Earth's satellitte system was taken out, crippling communications and SatNav services.
Then, and this is the part I'm struggling with, components of the large wall descended from orbit and landed in designated spots - aligning with their neighbouring components to form the wall around city centres.

I can see that isolating pockets of humanity would be strategic positive, as it helps stop people banding together in larger groups and thus resistance is limited. Yet it seems like a huge amount of resources to dedicate.

[FaxModem1]

I haven't seen any of the second season, only the first. But the alien colony on the moon seems to be the main reason why the aliens are here on the first place, using humans as some sort of slave labor.

The first season shows that the areas outside the controlled colonies are empty of people, for unknown reasons.

So either they want us as some sort of resource, or they need something on the moon.

Not sure which.