Who is in Control of the Earth?

Some Jehovah's witnesses came by today and handed me a pamphlet with the question, "Who do you think controls the earth?" The answer the pamphlet gave was that Satan controls the earth, and they cited a few verses to justify their answer.

I think the question is interesting, as there are many related issues in the ballpark that perhaps are being wrapped into it. "Control" is a very different sort of a thing than, for example, "authority" or "sovereignty". I think if we separate all three of these concepts, as they are distinct, then we can more easily answer the question of who is in control of the earth.