https://youtu.be/Ku1zyBr8Zb8?si=4jczIrS37yMggMpA&t=872

I have this video starting at 14:32 and ends on that subject at 19:50. Much of the rest of the video is speculation and alien contact accounts.
This is one of the only videos I have found that is discussing the possibility of unfriendly aliens that consider humans their enemy.
Since there are several different species of aliens, each one have their own agenda, which means one explanation for all of them does not apply.

I was told by a CIA official 30 years ago that the US was concerned about one species of alien that may attack earth in the future, and the US was preparing for that possibility. However, the distance from their home planet was so great that making invasion plans for such an attack would take years to accomplish and would be logistically difficult for them. IMO I don't think it will happen, but a fake alien attack could take place by the globalists for ulterior motives of controlling the masses and setting up a one world government.

In the meantime, the US and their private company contractors have been reverse engineering alien space craft and a variety of advanced technologies, gaining weapons systems and achieving parity with the aliens.
Whether aliens exist or not has already been well documented - they do exist, but full public disclosure is not forthcoming for defense purposes and to allow the globalists to gain enough power to advance their financial positions, fine tune medical advances for human longevity and also set up a break away society on another planet.

In the Biblical sense aliens for the most part can be considered demonic since they have proven to abduct, experiment on and kill human beings. And those that are supposed to be "good" aliens aren't helping "We the People". Which means if they aren't with us they are against us. Or, if they aren't warning us or helping us, what good are they?
Very few accurate conclusions can be made about the ufo/alien subject. Since that is the case, their existence does not play a major role in our lives today. GE