Have you seen what is left of Edom? Do an Internet search for the ancient city of Petra, or just go here: http://en.wikipedia.org/wiki/Petra
Imagine that the place is not in ruins, that things are painted, plants are everywhere, and there are people and so on. See it as a vibrant place.
Nevertheless, because Edom was very well hidden, and hard for an enemy to attack, the nation believed they could not be conquered, but the Lord said,
“For indeed, I will make you small among nations, despised among men” (Jeremiah 49:15).
It was not that the Lord wanted to pick on Edom, but they had exalted themselves through the usual sins of nations, especially ancient nations, and so the Lord had to bring them down, and now the kingdom no longer exists.