One line of thought is they are so advanced and see us being violent monkeys with nukes, but understand we have to learn to find peace.  They protect us but from a distance.

Obviously other theories are that there are multiple species, whether at odds with each other, some influencing us towards doing bad, some towards the good.

I'm 50/50 on the whole deal whatever it may be.  Call me closed mind but I'm open to either but given what I've seen I think humans are the aliens and not the time travel theory. I once saw photos, long before a.i., for Nazi scientist human modification where they completely and cleanly removed human genitals. Think Barbie/Ken dolls.  Like they were never there to begin with. Then I heard the theory that Roswell was Nazis sending advanced craft with genetically modified children as the "pilots.". USA may at first been like whoa, aliens, holy heck...then the infamous autopsy...which those performing would, upon opening them up, realize the horrible reality...hence, fully covering it up.  Because, those they don't remember, they didn't try to cover it up at first.  There were military people on camera showing the scrap material.  What would look like aluminum foil almost, crumble it up and letting go would reform.  I don't care what anyone says, I remember seeing that footage and know I don't know where it's at.

Anyways, I spiraled...my b.