The major, with the withered hand, wants life to make sense. He is married to a young woman who unexpectedly dies from pneumonia. He is confronted with the seemingly arbitrary unfairness of life. Already skeptical of the machines, the major does not believe his hand can recover completely. At the end of the story, the major stares out the window ignoring the pictures of rehabilitated hands which are meant to inspire and give him hope. That being said, the major is left in despair or, at best, uncertainty. After his wife has died, the major tells the American not to get anything (i. e. a wife) that can be lost. This speaks to his grief following his wife's death; but it also speaks to the war itself and suggests that in war, there is only loss. The major feels utterly defeated. 

The American wants to be out of the war. But since he is there, he at least wishes to be brave and to genuinely feel that he's earned the medals he wears. He doesn't feel that he is on the same level as the other Italian soldiers. So, in addition to being detached by the war and being alienated in "another country," the American is further alienated because he does not feel like he belongs with the Italian soldiers: 

I was a friend, but I was never really one of them after they had read the citations, because it had been different with them and they had done very different things to get their medals. 

The narrator wishes he had been brave and then he considers going back to the front, wondering how he will be when he gets back. The story ends before this is answered, so there is no way of telling how the narrator will respond again when bravery calls. But up to that point, the narrator felt inadequate in respect to his own courage in the war. 

Not much is said about the other four Italian soldiers. Of the first three, one "was to be a lawyer," one "was to be a painter," and one "had intended to be a soldier." Note the difference of description from "was to be" with the first two and "had intended to be" with the soldier. This suggests that the others did go on (succeed) to these professions but there is some uncertainty about the third, the soldier. This, also, is not resolved. Interpretations will vary about what this means but it seems to suggest that "being a soldier" is simply quite different from "being a lawyer." If anything, it is easier to say how successful a lawyer might become but not quite as easy to define a "successful soldier" because even one who illustrates bravery could leave the battlefield feeling detached after witnessing death. So, even with the success of bravery comes the loss of humanity. It is more complicated then to talk about success and failure in terms of being a brave soldier (than it would be to talk about being a successful lawyer). The fourth soldier wore a black handkerchief because his face was being rebuilt. He eventually became a banker in South America. In these sections describing the soldiers, the narrator makes an important point: 

But this was a long time ago, and then we did not any of us know how it was going to be afterward. 

Filled with such uncertainty and detachment, each soldier perhaps longs for certainty, and in the end, to be "attached" rather than detached. While some of the soldiers may have succeeded in terms of bravery, they have yet to feel secure and certain about their futures.