Why would a story be written in third person perspective?

The writer was showing us all the things that as a cilvian alot of us that were not there would not realize unless some that was there explained, thus he did in drawing a mental picture of all the things of home were the heaviest things they carried it was not the physical things that way as heavy as the mental things they carried, and some of them carried alot, but a picture of the ones they loved and may be lost these are the things that weighed on them the most, and because of this weight it cost many lives and is still taking lives today,,all because of the way those back home look in shame as though serving their country was a bad thing, as he even showed in some of his own friends lost their life after coming back from the war, well written book.MOTHAFUKAR!!!!!