User blog comment:Calbeius or Urukgoth/A Calbeius Original: The Explanation of Evil in the Fourth Age/@comment-27723099-20160104084501

In a story Tolkien started to write about the Fourth Age, the men of Gondor would slowly fall into corruption and maybe even praising Melkor or Sauron, like the Numenoreans did before. No such powerful human realm can exist without these problems.

"I have written nothing beyond the first few years of the Fourth Age. (Except the beginning of a tale supposed to refer to the end of the reign of Eldaron about 100 years after the death of Aragorn. Then I of course discovered that the King’s Peace would contain no tales worth recounting; and his wars would have little interest after the overthrow of Sauron; but that almost certainly a restlessness would appear about then, owing to the (it seems) inevitable boredom of Men with the good: there would be secret societies practising dark cults, and ‘orc-cults’ among adolescents.)"

- Tolkien's Letters #338