how does war affect human who fight its own battles and the societies that experience war base on the book named "the things they carried"

This is a thematic question. The single uniting theme of this book lies in the burdens that soldiers bear, both physical and emotional. The title points this out, and most of the stories -- in one way or another -- are about burdens the war forces upon the soldiers. The burdens almost always seem too much for them to carry. Jimmy Cross is responsible for the lives of all of his soldiers, but he is unable to keep all of them alive. The soldiers carry drugs and lucky pantyhose and Bibles but most of these fail to keep them safe. Many of their burdens seem primal, almost biblical. "Well, that's Nam," says one character. "Garden of Evil. Over here, man, every sin's real fresh and original" (76). Part of the reason the burdens seem unbearable, the evil so fresh, is that the men are so young. They have many more years to carry the same burdens. Tim O'Brien must carry the burden of having killed a man for the rest of his life. You can check out more themes at the GradeSaver link below: