Tolkien starts by reiterating that LOTR is not an allegory of Atomic power, but rather of "Power (exerted for Domination)". Of course, as Tolkien points out elsewhere, the concept of the Ring was created long before the Manhattan Project. But it is interesting that here he acknowledges, despite his oft-cited dislike of allegory, that his story IS allegorical.
He goes on to state that nuclear physics can be used for that purpose (domination) but that it doesn't need to be. He states:
It is interesting that Tolkien cites Chesterton here, a rather controversial figure. But the statement that he quotes sure does resonate in modern times, doesn't it? The 8-track, here to stay. Cassette tapes, here to say. VCR, dvd's, the first generation of personal computers; there are too many examples of the fruits of technology that are out-of-date almost as soon as they are widely accepted.If there is any contemporary reference in my story at all it is to what seems to me the most widespread assumption of our time: that if a thing can be done, it must be done. This seems to me wholly false. The greatest examples of the action of the spirit and of reason are in abnegation. When you say A[tomic] P[ower] is 'here to stay' you remind me that Chesterton said that whenever he heart that , he knew that whatever it referred to would soon be replaced, and thought pitifully shabby and old-fashioned.
More importantly, this concept of "abnegation" is obviously of prime importance to Tolkien (he repeats the reference later in the letter. The first definition of the word that I find is "renunciation of your own interests in favor of the interests of others." The dictionary could just as well place a picture of Frodo Baggins next to it!
Despite his disclaimer that his story is not about Atomic power, he still manages to make the analogy, stating that "there will have to be some 'abnegation' in its use, a deliberate refusal to do some of the things it is possible to do with it, or nothing will stay!" Just as Gandalf and Galadriel (and to some extent Aragorn's) deliberate refusal to use the Ring saved Middle-earth from a terrible fate.
But as soon as Tolkien sets up this comparison, he shoots it down as unimportant:
There is so much here to talk about; I'm just going to touch on some of it for now, and then let it simmer. Usually when I have quoted this passage before I have started with "The real theme ..." but I think the statement makes more sense within the greater context. The whole theme of power and domination is, as Tolkien says, rather passing and ephemeral. That is because it is basically the story of the actions of mankind. The more "much more permanent and difficult" theme is rooted in the actions of God. At least that is how I see it.However, that is simple stuff, a contemporary & possibly passing and ephemeral problem. I do not thing that even Power or Domination is the real center of my story. It provides the theme of a War, about something dark and threatening enough to seem at that time of supreme importance, but that is mainly 'a setting for characters to show themselves. The real theme for me is about something much more permanent and difficult: Death and Immortality: the mystery of the love of the world in the hearts of a race 'doomed' to leave and seemingly love the world in the hearts of a race 'doomed' to leave and seemingly lose it; the anguish in the hearts of a race 'doomed not to leave it, until its whole evil-aroused story is complete
I'll leave it there for right now, and ruminate further, and hopefully get the thoughts of some others, before commenting any more about this stuff, or moving on to the rest of the letter.