So this is diplomacy (implied spoilers)

For me this movie confirmed what this concept represents in its deepest sense. Although it has a very positive connotation in society and diplomats are seen as some sort of white knights, it actually is a cutthroat discipline focused solely on getting what your side wants, at the expense of any moral concerns like empathy and compassion.

I tried seeing the two opponents in this movie as neutral, and witnessed in the end only a trusting side being taken advantage of by a more scheming, conniving side. The fact that the city survived by these means really meant nothing in this mental exercise. True justice means that nobody loses (this is not practiced currently or historically) and, in the end, the general's family was promised safety that was delivered by chance and not by the promisor, who endeavored to fulfill an obligation with no intent of carrying it through.