A necessary evil.
"Evil prevails." Yuri Olav in "Lord of War"
Nicholas Cage's Yuri Orlav is the embodiment of the situationally ethical arms dealer who justifies his profession with such specious arguments as supplying arms to countries for their "defense" or because someone will take his place if he leaves--unsatisfactory justifications for families of slaughtered African refugees and bloody poor excuses for the US government.
Director Andrew Nicol takes too long in Lord of War to establish the flawed Yuri through a series of expected scenarios leading him into the rarefied position as top gunrunner in the world, with powerful and dangerous leaders willing to give him money and protection in exchange for arms. Only after Ukrainian Yuri has become comfortable with his moral ambiguity and his family is ignorant of his trade does the director/writer introduce the tensions between Yuri's better angel and greedy devil. This conflict is also couched in the most general and clich?d ways to the extent that his flawed reasoning remains intact (his brother, Vitali, played by Jared Leto, provides the alter ego of slacking but morally outraged pretty boy) but is counterweighted by his concern for his wife and child. His relationship with a brutal Liberian general pits Yuri's ethical life against his family life.
Yuri's voiceover narration takes a few shortcuts to his character while exposing the essentially conflicted nature of a trade where he is so good at what he does that he is reluctant to leave. "I am a necessary evil" is the closest he comes to recognizing his corruption. Nicol layers enough wisecracking comments from Yuri to help mitigate the overwhelming sense of Yuri's moral decline.
The contribution of this character to modern fictional reality is that politicians and business people are faced with the same dilemma of wishing an end to the conflict in Iraq for reasons of honor but hoping for continuation for pragmatic reasons such as profit (as usual Halliburton and Cheney come to mind). When the closing credits remind us that the US and Russia are among the top arms dealers in the world, Nicol's allegorical subtext rises like fat to the surface. Too late to make it a great action film; too didactic to make it great art.
As for the endurance of evil, Hawthorne also had the insight in "Young Goodman Brown": "Evil is the nature of Mankind."