After this I saw another angel coming down from heaven. He had great authority, and the earth was illuminated by his splendor. 2 With a mighty voice he shouted:
“‘Fallen! Fallen is Babylon the Great!’[a]
She has become a dwelling for demons
and a haunt for every impure spirit,
a haunt for every unclean bird,
a haunt for every unclean and detestable animal.
3 For all the nations have drunk
the maddening wine of her adulteries.
The kings of the earth committed adultery with her,
and the merchants of the earth grew rich from her excessive luxuries.” (Revelation 18:1-3 NIV)
At the end of the tribulation period God will finally get His vengeance on Babylon as predicted in the prophets. Physically, He will get His revenge by destroying the actual city of Babylon with natural disasters (Revelation 16:18-19) (Isaiah 13:1,10-13), and human armies (Revelation 17:6, Isaiah 13:4-5, Jeremiah 50-51), until it is left completely desolate (Revelation 18:21-23, Jeremiah 51:37, Isaiah 13:20-22). God is angry at Babylon for maliciously destroying the temple of God (Jeremiah 51:11) and for the blood of the martyrs that they will kill in the end times (Revelation 17:6).
Spiritually, God will get his revenge on Babylon by overthrowing the evil Satanic governments of the world and replacing them with one true King, Jesus Christ, who is righteous, loving, and powerful. In that day they will say: “the kingdoms of this world have become the kingdoms of our Lord and His Christ, and He shall reign forever and ever” (Revelation 11:15).