Ways and Means
It's this open "hope without assurance" that lies behind one aspect of Catholic thinking that affects the entire story of LotR, especially, it seems to me, through the nature of the Ring itself. There are many debates in our own world, some general and some very specific, about whether the end justifies the means. To an orthodox Catholic, which Tolkien unquestionably was, there is no debate. The answer is, has always been, and will always be "No." To follow an evil path, even as a way to reach a good end, is to despair of any solution other than the one we see and to depend only on ourselves, not leaving room for other powers, including Providence, to act. It also makes the statement, of course, that we know what "end" is best; Saruman is an example of what that pride can lead to.
I've come to believe that this is, in large part, what's behind the repeated admonition in LotR that the Ring cannot be used for good, even if someone were to wield it with the best of intentions and with enough power to bend it to his or her own will. The Ring "works" by controlling the wills of others. As we'll discuss more in the next section, Tolkien believed that any action that represses the free will of another human being is intrinsically, by definition, evil. So, no matter how good the end might seem, using the Ring as a means toward it can only turn the entire endeavor to evil.
The Ring isn't the only temptation toward allowing the end to justify the means that we see in LotR. In his attempt to turn Gandalf to his way of thinking, Saruman talks of what they could accomplish if they side with Sauron:
We can bide our time, we can keep our thoughts in our hearts, deploring maybe evils done by the way, but approving the high and ultimate purpose... There need not be, there would not be, any real change in our designs, only in our means.
It's especially telling that Saruman's main argument for siding with Sauron is that "There is hope that way," while he sees no hope left in "Elves or dying Númenor." Because he's limited his own hopes to what he can control, or at least understand (and in his pride, he probably doesn't believe anything exists that he doesn't understand), he leaves no room for means that he doesn't expect - such as hobbits! As Elrond says at the close of the Council, "Who of all the Wise could have foreseen it? Or, if they are wise, why should they expect to know it, until the hour has struck?"
There's an example in "The Siege of Gondor" of Tolkien not being afraid to look at the other side of a question:
[Denethor to Faramir] 'Ever your desire is to appear lordly and generous as a king of old, gracious, gentle. That may well befit one of high race, if he sits in power and peace. But in desperate hours gentleness may be repaid with death.'
'So be it,' said Faramir.
'So be it!' cried Denethor. 'But not with your death only, Lord Faramir: with the death also of your father, and of all your people, whom it is your part to protect now that Boromir is gone.'
Denethor is referring here to Faramir letting the Ring "slip through his fingers" instead of bringing it to his father as his father believes Boromir would have done. By this time in the story, we've seen enough to know that everything Gandalf says about the Ring and about Boromir's reaction to it is true. But Denethor's argument does have some logic to it, for someone who hasn't seen what the Ring is capable of. For some reason (humility, perhaps?), Faramir understands the danger of using the Ring, which for some reason (pride, perhaps?) Denethor doesn't. Denethor falls into despair because in his pride he thinks he has the power to control the palantir but, like Saruman, is instead captured by it. He allows the Enemy to show him his great forces, but isn't open to the hope that there are forces on the side of Good that he may know nothing about.
But, still, I doubt if I'm the only one who has an ever-so-slight impulse to sympathize with Denethor's side of the argument. Tolkien doesn't give us an easy answer to it. At the point in the story when this conversation takes place, Faramir doesn't know what the result will be of his decision to allow Frodo to keep the Ring and to let Frodo and Sam continue their Quest of Mount Doom. Like the people at the Council, he doesn't see how it could end successfully. But also like the people at the Council, he realizes that he cannot see every end. It's possible that bringing the Ring to his father might have saved the City, but it's certain that doing so would have been wrong. He agrees with Frodo's statement that the only type of victory that could come through use of the Ring would be the type that would turn Minas Tirith into a second Minas Morgul.
On the online Tolkien Sarcasm Page there's a list of "Ten rejected plot twists for The Lord of the Rings." One of these is:
Boromir uses the ring, saves Gondor, destroys Sauron and becomes a wise and benevolent ruler. Book ends 40 chapters sooner.
I think this is pretty funny, as I do most of the things on The Tolkien Sarcasm Page, but it's a storyline that Tolkien would not have written.