Protagonist (named Alan?) is a novice in a monastic order of interstellar translators/lawyers/negotiators. The story covers his first position, hired out on a trading mission to a civilization without native metals. During the mission, he learns that the official non-interference and non-violence positions of his order are not shared by (some of?) its leaders. References to and translated quotes from Machiavelli are used often.
This is the Cyril Kornbluth story "That Share of Glory". It happens to be a personal favorite of mine.
You've remembered it extremely well, except that the protagonist's name is Alen. As you say, there are numerous quotes from Machiavelli throughout, including the title.
It was featured on the cover of Astounding Science Fiction when it first appeared in January 1952.