Graham, I pointed out in The Coming of the Son of Man that the accounts of the seven seals and the seven trumpets draw consistently on Old Testament passages that speak of judgment on Israel; the account of the seven bowls uses language and imagery from passages that speak of judgment on the enemies of Israel. You mention Revelation 17:18, but again I fail to see how John’s readers in the Roman world would not have identified the ‘great city that has dominion over the kings of the earth’ with Rome. Certainly Jerusalem is regarded as hostile to God and subject to judgment, but there is no reason to exclude Rome from the same fate. Babylon in the Old Testament is the instrument of divine judgment and then becomes subject to judgment. What objection is there to supposing that John saw things in much the same way: Rome is the contemporary Babylon which God will use to punish rebellious Israel, but which will then itself become subject to judgment because of its idolatry, wickedness and imperial arrogance?