After introducing the novel, she talks about how it is about preserving good things in the midst of destruction, decline and decadence.
If you know the novel, read this. If not, go to her post here and read her brief introduction to it first. Then continue reading below.
At the moment, none of us expects all of human civilization to be wiped out by nuclear weapons. But there are plenty of destructive cultural forces to go around. In the end, what will be preserved will be preserved only by those who have a powerful creative impulse, an impulse not only towards saying what is wrong with the world but also towards saying what is good, what is great, what is beautiful and important, and what therefore must be preserved, however we are able to keep it.
If you are to be a preserver, you must know not only what you oppose, what you fight against (though you do need to know that) but also what you love, what you guard, what you uphold. It may be the truths of theology, of philosophy, or of science. It may be dance, literature, mathematics, music, or the beauty of visual art. It may be the lives, minds, and hearts of children. It may be the order and peace of a home or the love between man and wife. All these things can be served and nurtured. There are always good things, great things, things worth knowing and worth doing, to the greater glory of God. How blessed we are that, unlike the earliest monks of the Order of Leibowitz, we are able to understand what we preserve, to know not only that it is valuable but why it is valuable.
Everyone who loves the permanent things is invited to join the Order of St. Liebowitz.