Who is the enemy?

Watching Good Morning Vietnam, there is the constant juxtaposition of humanity and war plus humor and sadness throughout. 
And then the near final scene where Adrian Koronhaour chases a young man, the brother of his love interest through the back alleys of Saigon and finally meets up for the big confrontation. Adrian screams at him for being both his friend and VC “terrorist.” And the young man screams back…

Alexander asked at breakfast the next morning, “weren’t the VC kids fighting just like the patriots in the American revolution ? To defend their country against the big strong enemy just like the Americans fighting the British during the Revolutionary War? Is that what you mean when you say, “The victor writes the tale” Alexander queried? …Nicholas…”or to the victor go the spoils”? Yup, as I often say, the answer to many questions?

“it depends…”