Secret Military Governments – UFO coverup?

Tell me something, if there was a secret government and it was covering up UFOS and alien interaction

What would the aliens be wanting from US?
What would we want from them?

Watch UFO Files on the History Channel.
Is not so much of protection or National Security crap, they let immigrants cross everyday.
BUt is more of wanting superior technology, Military INdustrial Complex…50+ years later, what has change!!!!!???