pregno Your solution is too simplistic! You seem to have the view that people are born evil (Really? Can you look at a newborn baby and believe that they might be inherently evil?) and that the solution is 'simply' to lock them away for evermore.
I understand your point that dangerous criminals need to be kept away from the public, of course they do but you are still not thinking about what WE as a society can do to prevent such atrocities happening again and again and again. You are also not considering the possibility that rehabilitation is possible for SOME criminals.
You made the point earlier that not all children from dysfunctional families become criminals (thank goodness!) Perhaps we ought to be looking at those individuals to see what is different about them and their lives that has enabled them to not repeat the abuse they suffered.
Maybe there are other influences in their lives; other family members, social workers, counsellors, teachers, youth workers, well-meaning neighbours... someone who has been able to be a positive role model for that person or someone who has been able to offer a sanctuary of sorts for them when they have been troubled.
Maybe, for others, something else in their life has enabled them to escape the cycle of abuse and violence; that could be anything from religion to education to a passion for music or art...something that has helped them to see that there is a very different world out there in which they can be appreciated and can achieve.
Perhaps this sounds idealistic; I'm simply saying we should examine the factors that contribute to a troubled young person going on to be a violent offender or not.
As individuals, what can we do? Be good role models to our own children and to other people's children; be good neighbours and good friends. Not suggesting people need to be interfering but just aware and empathetic.
I honestly think you're being simplistic, merely because it is the easiest option; sorry.