Phillip Goodman wrote an article entitled "The Identity of the 7 Heads and the 10 Horns on the Beast of Revelation 13". His list is below with Iran being designated as the 11th. Unlike many who are trying to force the USA into prophecy he keeps focus likely were it should be. While the United States might be under a special kind of conquest of Great Britain or perhaps of Rome, it seems rather evident that de jure and organic America separated from Britain around 1776.
Unlike many, he takes a perhaps less Western-European(Arabian?)-centric view following the idea of Eastern 5 Toes/Horns and Western 5 Toes/Horns.1. Britain
2. France
3. Spain
4. Italy
5. Germany
6. Greece
7. Turkey
8. Syria
9. Egypt
10. Iraq
11. Iran
The people pushing the USA into the wrong focus might also likely into Scofieldism and not wanting to see that the woman riding the beast might have something to do with a Roman or Babylonian religion rather than a North American one. Perhaps the American Colonists recognized this and Divine Providence worked in favor of the American Colonists because they knew what they might have been dealing with?
All the attention the USA has been getting just might be a big distraction.And the kingdom and dominion, and the greatness of the kingdom under the whole heaven, shall be given to the people of the saints of the most High, whose kingdom is an everlasting kingdom, and all dominions shall serve and obey him. Daniel 7:27
Related:
Europe In Bible Prophecy
Cyrus Scofield - Who Was He?
The Greatest Hoax