Most of the actors, and writers were hardcore leftys.
My marxist teacher in college made the class watch it and write about it.
I thought it showed the evil side of marxism for what it really was.
She (admantly) disagreed by saying that pol pot corrupted marxism and that it showed proof that America was to blame.
The movie isn't conservative, its just anti-pol pot and anti-american at the same time.
It also is written just the way so that anyone can draw any conclusion they want from the movie.