While literature speaks to many people in different ways, I believe that in Tim O'Brien's "The Things They Carried," we learn that many people have ways to keep that which is familiar close to them. The comforts of one man are meaningless to another, but the experience of war is a terribly personal experience as well.
Lieutenant Jimmy Cross carries a stone his "girl friend" sent to him from the beach. She writes to him, but he knows the comfort is empty: she is not his girlfriend—for a while, the thought of her comforts him. Kiowa keeps a Bible with him and a hatchet that reminds him of the Native American culture from which he comes.
One man notes that the "moral" is not to do drugs—when Lavender is killed—someone who did do drugs. He tries to come to terms with Lavender's death in a corner of his mind. The truth is that war makes no sense. The things the men carry are things of war (weapons and supplies), but also things that keep them grounded, help them to cope with death and possible death that hovers over them at all times.
There it is, they'd say, over and over, as if the repetition itself were an act of poise, a balance between crazy and almost crazy, knowing without going. There it is, which meant be cool, let it ride, because oh yeah, man, you can't change what can't be changed, there it is, there it absolutely and positively and f***ing well is.
They were tough.
The things they carried were necessary for war and necessary to maintain some sanity, expecially in a world where there seemed little hope for sanity—and often little hope for survival.