By control I mean the aliens would be small in number compare to billions of humans. What better way to get some control than to offer the humans some trade for technology and weapons. It is true, the aliens here on Earth may already have control or have made deals with various countries. To what purpose they would barter with humans, who knows? Nefarious or good, I hate to think what might have been negotiated. From certain reports over the years, it seems that UFO ships have been able to activate or shut down missile silos. A very frightening thought when you think about it.