So, Cormac McCarthy lived in El Paso for a while, presumably traveled in Mexico. And not in the best of circumstances, he was dirt poor. I think that when he set out to write a western/military history novel, he asked himself, "what sort of man would have lived where I live, 150 years ago?" And then he wrote a series of characters who are archetypal or at least typical of the setting, but overshadwed by it -- because west Texas, south Texas and desert Mexico are overwhelming, scary places. They're dry, they're unforgiving, and they're empty -- and so are McCarthy's fucking characters. I love it. His depiction of violence is just realism. I don't see the need to subscribe symbolic value to it. Texas/Mexico (the distinction was blurry then) in the 1800s was a really dangerous place, with a lot of competing factions centered in a small area. All the history of the time that I've ever read indicates McCarthy's violent scenes are by no means beyond normal.