In a recent correspondence with a friend who is much more of a Girardian purist than I am, he said something like "all violence is righteous." He was referring to the Giardian insight that human beings have a deep mimetic propensity to deceive and blind themselves, especially when it comes to matters of violence.
The behavior of a lynch mob looks very different from outside than from inside, and it is easy for outsiders to project into the mob a feeling that is entirely alien to it. The outsiders think that such a mob is incurring great guilt (which they in fact are), but the psychology of the mob is quite different. As far as they are concerned, they are relieving guilt, not incurring it. They are punishing the guilty, and they are absolutely settled on the objective fact of their victim's guilt. They hang the guilty man, and go home to sleep sweetly. All violence is "righteous."
But what begins as an important psychological insight begins to fall apart in our hands if we try to absolutize it. If we absolutize it, then we have to say the same thing about the state police in riot gear who show up to save the life of the lynch mob's victim. This insight, if we absolutize it, gets away from us, and has the effect of leveling all forms of violence everywhere. Trial? Guilt? Due process? Self-defense? All just words -- because all violence is (self-justified) righteousness. So there is no possible way that this view can be squared with Scripture's teaching on the many forms of violence that are genuinely righteous.
Another problem is that, like many absolutist positions, this one excludes itself from the standard it purports to apply to everything. In a similar way that the relativist says that there is no truth, asking us to believe this one truth of his, so also the Girardian purist can "see through" every rationalization for violence. "That's what they all say. All violence is righteous." Okay, but all denunciations of violence are righteous too, and are themselves a form of soft violence. One man lynches another in order to remove guilt from the community, and to feel a sense of moral superiority. And the pacifist wants to bring his kind of pressure to bear, shaming us with placards about bombers and bake sales, hungry for that same sense of moral superiority. "All denunciations of violence are righteous."
At the end of the day, living in society means making certain people do things they don't want to do, and making sure to do this to the people who don't see things as clearly as you do. Traditionalists like myself want these sorts of ruffians to be guided into rightousness by means of a billy club delivering a few brisk ones about the head and shoulders. Non-traditionalists want to wrap them up in three down comforters before delivering the therapeutic group hug, but societies always say "my way or the highway."
The only kind of absolutism that won't do this to you destructively is scriptural absolutism. The Word of God is perfect, and is rigid where it needs to be, and is supple where it needs to be. If we take any one tenet from it, isolate it in our own laboratory, and absolutize that, we soon find ourselves running headlong into follies and contradictions. Once we start to "see through" everything, we find ourselves in a hall of mirrors, unable to see through anything.