Why so defensive? I was saying the same thing as you.
Obviously locking up violent offenders, keeping them locked up and continuing the process over and over and over again will keep all the bad ones off the streets and the hardworking members of society safer. Except of course for their very first violent crimes, gotta let those occur before we lock em up.(?)
Mind you, it doesn't address the problem of what is causing so many people to commit these violent crimes in the first place. Perhaps that's just the way it is?