It would not be surprising that their are other life forms out there. A theory that I do believe is possible. I honestly hope that if there is, they are more intelligent than we are, perhaps they are going to be the ones to make "the change". In all seriousness, if there is other life form(s) there is really not a lot to be done about it as I am sure they are not going to ask our permission for use of air space.
If you believe as I do ,from a lot of images, reports and eyewitness, that beings have already come they already know we are here and have know for a long time. Probably not to much of a threat, The might beam you up though... guess that threatening