[ToddT]

Hmm Two interesting scenarios of pop , interesting i have read a short on the second and a series of books on the first and a short story.
Short story aliens have already invaded earth as a oupost/resupply base, stories point main character trying convince underground the futility of trying over throw the alien invaders (tech so advanced it was like magic)
book series was (Dan Foster)Earth was discovered by a alien probe, fortunately the benign variety. they sent a small recon group to check earth out. after their 1st and second probes were shot down. From the aliens point of view this was highly irregular, most civilized worlds did not have means to readily shot down probes on sight. the normal behavior of most races was non aggressive unless given no other choice. currently at war with a psychic race that had the same view point, but had a twisted way of looking at it (the could manipulate other races minds, so violence wasn't only used when resisting race failed to se reason).
Any way the alien recon group was amazed/stunned at humans raw strength and tendency towards violence. We turned out to be the perfect weapon against the psychic race. We where from the aliens point over unussualy armed to the teeth and un to psychic manipulation, some part of our minds didn't repond well to mental intrusion, fatal to aliens.

now as to aliens tech, status short story, not sure by who, can't find the correct issue of " Analog" ascience fiction pulp type magazine back in 1985. We are about 20 years more advanced in some areas than we are today and have a ship out bound to somewhere beyond the asteroid belt, currently in the belt. They dectect some ships appearing out of no where, and head straight for earth. turns out the ships are a raidng force.
the kicker other than faster than light travel and anti-grave type propulsion, they where no more advanced then earth was in the middle ages. Turned out in the story faster than light travel and gravity control was absurdly simple and we had missed it, and had taken the other fork in the road. So after earth rounded up the invadeing teddy bears (the aliens looked liked small bipedal bears) tot'n cannons and muskets, one of the invaders came to this conclusion, what have we done.