Gothic melodrama of the lowest order? Or social commentary?

So now able investigator Salander has assembled a list of horrifying unsolved murders over about a 20-year span, each one an attack on a woman in particularly gruesome manner. Each is somehow linked to a passage in Leviticus that proscribes a Biblical punishment for such things as wizardry, sex with animals. How many ways does this strain credibility beyond even the ludicrous, to the point where I just want to throw up my hands? That no one in Sweden would see a connection between these cases? That any one person could get away with these serial murders undetected? That any tortured mind would even pursue this course? That any one person acting alone could solve the crime in a couple of hours with a few Google searches? All of this is just evidence of a really creaky plot that has a veneer of contemporary realism but in fact is a gothic melodrama of the lowest order. What bothers me more is the implication that "The Girl with the Dragon Tattoo" is a book that examines violence against women. Does it? Or does it exploit violence against women for cheap plot points? The serial killer as Stieg Larsson presents him is so far out on the lunatic fringe as to not be representative of anything except a thriller-writer's imagination. The "advocat" who attacks Salander may in some ways be more typical - the upstanding citizen who gets away with it, even thinks that women like his sadistic bullying. That's a theme worth looking at - but does Larsson do so? Not really - he makes the advocat into a cartoon of evil, has Salander learn everything about him with a few quick searches and downloads, and exact her own gruesome revenge very expeditiously. In other words, he throws in these scenes for some excitement, or worse, but he's not interested in looking at the mind of an abuser. Look, this book is a tremendous success, so it must resonate with many people, and who am I to criticize that? And Larsson was probably a great guy, and I feel bad that he did not live to enjoy his success. But let's not make of this book any more than it is, a cheap thriller.