This verse is very helpful in assisting the child of God in properly identifying the spiritual meaning of the nation of Babylon:
Jeremiah 51:49 As Babylon hath caused the slain of Israel to fall, so at Babylon shall fall the slain of all the earth.
First, we read that Babylon caused the slain of Israel to fall. Who does Israel represent?
The answer is that Israel represents the New Testament corporate church. God raised up the Babylonians and they came out of the north to destroy the unfaithful people of God---Judah. Just as God raised up Satan (by loosing him) to come against the N.T. congregations for their unfaithfulness to His Word.
Secondly, the Lord says, that AT BABYLON will fall the slain of all the earth. This is part that many miss because they are convinced that Babylon only represents the churches.God is saying that He utilized Satan and his evil kingdom to come against and destroy the churches. But afterwards, it is God's plan to turn around and destroy them. So, it is at Babylon that the slain of all the earth (the unsaved people of the world) fall.
Revelation 18:2 And he cried mightily with a strong voice, saying, Babylon the great is fallen, is fallen,...
At the conclusion of the Great Tribulation period (May 21, 2011) God then judges Babylon (the world) and brings about her fall (and of course the fall of her king----Satan).