In the New Yorker, Jared Diamond writes a long article with an interesting personal account of revenge cycles in Highland New Guinea:
Hiring, supporting, and rewarding all those allies was a complex logistical operation. Daniel had to feed them during the actual days of combat, to arrange for houses in which they could sleep, and even, as he delicately phrased it, "to provide ladies for the warriors when they were homesick." Daniel estimated that, in the three years that it took him to get his revenge, he had to furnish about three hundred pigs. By custom, the pigs to be slaughtered during that long phase of preparation should be not one's own but, rather, stolen from the enemy clan. Yet Daniel had to be careful to steal only Ombal pigs and not to make the mistake of stealing pigs from other clans; otherwise, he would acquire new enemies.
Many students of anthropology may have seen videos of the large, showy, and ineffectual-seeming "public fights" between groups, and taken away the impression that such small-scale warfare could not be very dangerous. But in the context described by Diamond, this is only the surface of a deeper, more earnest pursuit:
Daniel emphasized the importance of distinguishing between long-range public fights and close-range private ones. He contemptuously described the former as a "small boys' game shoot." As he explained it to me, "Public battles are open not just to experienced fighters but also to new trainees, new allies hired to come and gain confidence, and fun-seekers. In a public battle, the fight-owners have the opportunity to see who really are the best marksmen, with the necessary experience to make quick but correct decisions." Such warriors are selected for the much more dangerous task of private fights, in which hired teams of stealth killers prepare ambushes. "That requires nerve, judgment, and presence of mind, to select the right target, and not to panic and shoot the first man who moves into a shootable position," he said. "Boys and young men are prone to make such mistakes and hence are excluded from the stealth parties."
At the outset of his essay, Diamond suggests that revenge cycles in small-scale societies are equivalents of the dehumanization induced by wars between states. I think this part of the essay is simplistic: he might have profitably explored the differences, the depth of which is suggested by the different psychological reactions that he mentions.
But the end, a personal account from a different culture, is much more evocative.
UPDATE (2009-04-23): Jared Diamond has been sued by two New Guinea men over the content of this article.