Plan 9 from Outer Space1957

Col. Edwards:
Why is it so important that you want to contact the governments of our earth?

Eros:
Because of death. Because all you of Earth are idiots.

Jeff:
Now you just hold on, Buster.

Eros:
No, you hold on. First was your firecracker, a harmless explosive. Then your hand grenade: you began to kill your own people, a few at a time. Then the bomb. Then a larger bomb: many people are killed at one time. Then your scientists stumbled upon the atom bomb, split the atom. Then the hydrogen bomb, where you actually explode the air itself. Now you can arrange the total destruction of the entire universe served by our sun: The only explosion left is the Solaranite.

Col. Edwards:
Why, there's no such thing.