See an article summarizing this thesis from the Catholic apologetics site Defending the Bride HERE

Dr. Scott Hahn in his tape series "THE END" on the book of Revelation argues for the position that the Whore of Babylon is not Rome, which persecuted the Catholic Church, but instead is apostate, worldly Jerusalem which rejected the Messiah. He concedes that this is the minority position but the Biblical evidence that he gives is overwhelming.

Roger writes: This is listed as material that someone gleaned from listening to Dr. Hahn's tapes, so it should by no means be assumed that Dr. Hahn has nothing more to say on the subject. I am just using it as a starting point to discussion. On to the material:

CODE NAME

Revelation 17:5-6 "On her forehead was written a name, which is a mystery, 'Babylon the great, the mother of harlots and of the abominations of the earth.' I saw that the woman was drunk on the blood of the holy ones and on the blood of the witnesses to Jesus. When I saw her I was greatly amazed."

Babylon was a code name, a "mystery." Compare how Jerusalem is referred to similar code names such as Sodom, Gomorrah, and Egypt. All of these, Sodom, Gomorrah, Egypt, and Babylon are all notorious enemies of God's people.

Isaiah 1:1, 9-10 "The vision which Isaiah, son of Amoz, had concerning Judah and Jerusalem in the days of Uzziah, Jotham, Ahaz and Hezekiah, kings of Judah.