Confusing plot

For those not from the area, the overall plot was clear, but the details and characters were so confusing.

was Leder an innocent guy that the guerillas tortured and then he became vengeful to the extreme because of the whole thing? I take it Edgar's character did not realize how brutal of a guerilla outfit he was getting into, but he was still a bad guy for getting into it, wasn't he? So why the fake dignity for his character? Why is he the "lead" guy in the movie? At best, he was a sap, but what was compelling about this guy that he is viewed as the lead character?

And what was the whole MOris and Ramirez thing? Moris wanted Ramirez offed because was wary of him rising through the ranks too fast? So he got some intermediary to attack Ramirez , ruin his face, and he used those two college kids as scapegoats? And so was it just a stroke of luck that Leder's guy happened to record some conversations which led to Ramirez's people and Moris's people just offing each other.

So at the end, is Edgar's character showing any character progression? I didn't get that feeling.