Josh Chafetz gets the film wrong when he claims that "Sin City depicts violence for its own sake. There's no purpose behind the violence -- it is simply presented as entertaining in and of itself." The violence in Sin City is deeply necessary, given the comprehensive betrayal and corruption of the powers that be in the film. Absent any significant protection from other sources, the women of Sin City (and the men who defend them, three of whom are the protagonists of the interwoven stories we watch) respond with increasingly brutal force to the physical threats outsiders pose. We are meant to shudder at the violence they mete out, and then meant to recoil even more at the awfulness of the situation in which they have been placed. What is the appropriate response when a group of people with no recourse to the police is being systematically hunted by a homicidal maniac protected by dozens of goons? A federal civil rights action? The world of Sin City is clearly not our world; the prostitutes there are written off by society in a way that they haven't been since Whitechapel in 1888, if ever. Perhaps Old Town is an anarchocapitalist dystopia, scattered with the corpses that private exaction of justice might demand.
There have been plenty of movies with more evil, murderous villains than the prostitute slayers and mob enslavers of Sin City. Is what's disturbing the vivid depiction of vigilante, Old Testament-style justice being imposed on such folk? We seen that before in plenty of Hollywood pictures. The discomfort of being put in the position of cheering for someone who has just single-handedly taken out a squadron of police officers? In the best moralistic tradition, just about everyone who dies at the hands of the three protagonists gets his just deserts (some of the cops may only be corrupt, not actively evil, but given the nature of the open secret they conceal, perhaps they could be considered evil as well). So is the real problem the presence of too much (white and yellow) blood? Forgive me if I don't find that particularly disturbing. We've seen much worse, and in living color.
Then again, Matthew Yglesias is slightly off when he puts forth Sin City as an antidote to "movies that portray violent acts -- people hitting each other, people shooting each other -- but that don't show the element of carnage and gore. The sort of bubble gum action flicks where people just seem to kind of collapse after being whacked on the head or shot." There are several scenes in the film in which Our Hero (Marv and Hartigan, and to a lesser extent Dwight) takes a bullet, a hit from a car, or what should be a concussion-inducing blow to the head and keeps on trucking. Violence in Sin City usually seems to have real consequences when directed at persons other than the protagonists. But other than that partial qualification, I'd say Sin City does an excellent job of depicting the escalating brutality that might follow from anarchy in an urban zone inhabited largely by people that the larger populace was not concerned with protecting. Sin City drives home the necessity of process and equality before the law, not the necessity of creative dismemberment.