Rev 18:23 "Your merchants were the world’s important people. By your magic spell all the nations were led astray."
Who are the "Merchants" and what was the "magic spell" that led all the nations astray?
The context names the Babylonians or the Chaldean's in v. 2, but then why would John be talking about an empire that no longer existed in that form? It is my understanding that the Roman empire was considered Antichrist by the early Church and by most Protestants, in both its forms, from Roman emperor to Roman papacy with Constantine leading the transition. What then does "Babylon" represent in the last days after Jesus Christ's ascension into heaven when John wrote this book? What is the meaning of the word "Babylon" and who are the merchants and what is the spell that led the whole Earth astray (in this context, i.e. Revelation 18:1-24)?
I understand you may be looking for an exegesis that fits within your existing view ('that 90% of the Book of Revelations is yet to be fulfilled'). However, I will be offering a more grammatical-historical approach.
The Roman Empire destroyed Jerusalem and its temple in 70 AD, an event Jews quickly began comparing to the destruction of Jerusalem and its temple by the historical Babylon in 587 BC. Other Jews contemporary to John specifically call Rome by the name 'Babylon' as a symbolic gesture.  Accordingly, most scholars understand the name 'Babylon' in the Revelation to be symbolic for the city of Rome. John further identifies Babylon as 'the great city' which is seated on 'seven mountains'. Again, most scholars see this as a deliberate reference to Rome's nickname as 'the city of the seven hills'. 
Revelation 18 is thus understood as a lament for the downfall of Rome (patterned after Ezekiel 26-28), particularly as this downfall is perceived by the very people who prospered by Rome's violence and wealth. These are the merchants John mentions.
The 'magic spell' (other translations say 'sorcery' or 'enchantments') is the word φαρμακεια (from which we get the word 'pharmacy'), which describes something involving drugs. It could be used for magic-based potions, poisons, or even medicine. Because John says this φαρμακεια is the manner by which Rome deceived the nations, he may be referring back to the 'wine of her sexual immorality', mentioned in Revelation 14.8 and 17.2ff. She has made the nations drunk on her wine, and led them in the persecution of God's people.
 1 Peter 5.13; 4 Ezra 3.1-2,28-31; 2 Baruch 10.1–3; 11.1; 67.7; Sibylline Oracles 5.180-201
 Cicero to Atticus 6.5; Georgics 2.534-535; Aeneid 6.781-783; Elegies 3.11.55-57; Tristia 5.69; Epigrams 4.64; Sibylline Oracles 2.19; 11.145-154; 13.61; 14.138Tweet