When O'Brien got the draft notice, everybody where he lived expected him to go fight in the war. However, he believed that war was not for him. The shame and guilt that he would feel from society caused O'Brien to go and fight in the Vienam War.
Man vs. Society
When O'Brien got his draft notice for the war, he was torn. He thought he was "too good for the war", but he believed it would be cowardly not to fight. He attempted to flee to Canada, but while stopping at an inn in Michigan, an old wise man takes him to the border to face the reality at hand, and choose ifhe will go to war.
Man vs. Self
When Mark Fossie brought his girlfriend MaryAnne to the war, he expected her to be there so that she could keep him company. However, she was traumatically affected by the war, and she grew a love for combat and the wild. When Fossie confronted her, thinking that he could turn her back to her nice self, but she protested claiming she was now part of the war, and their was no coming back.
Man vs. Man
You're in a place that you don't belong.
"The Things They Carried" Conflicts
Man VS. Self
When Norman Bowker got home from the war, he found it hard to adjust because of the terrifying things he saw during the war. One such event, Kiowa's death, proved to be too much for Bowker. He couldn't act like he normally would because he was too busy blaming himself for the death, instead of forgiving himself because it is not his fault.
Kiowa, nooooooo!!! I would save you but it smells so bad.