Klaatu Barada Nikto

"The universe grows smaller every day and the threat of aggression by any group, anywhere, can no longer be tolerated. There must be security for all, or no one is secure...

Now this does not mean giving up any freedom. Except the freedom to act irresponsibly. Your ancestors knew this when they made laws to govern themselves and hired policemen to enforce them. We, of the other planets, have long accepted this principle...

 Your choice is simple. Join us and live in peace, or pursue your present course and face obliteration. We shall be waiting for your answer. The decision rests with you."

Gort & Klaatu
The Day The Earth Stood Still, c1951