I was incarcerated as a minor for being monstrously violent. I was smart enough to get my life together. I saw these kids first hand. Many of them will never be able to be fixed. They were born different or fucked up beyond repair. My personal history makes me extremely sympathetic to people who want forgiveness, but not everyone is capable of earning that forgiveness.

It is also patently untrue that children's prisons in the US don't make efforts to help the prisoners. Where I was, there was individual therapy twice a week and group therapy three or four days per week. Sometimes less, if the unit was dangerous. But the staff cared and put in effort to teach us life skills, emotional skills, etc. I got three different job certifications in prison that I was able to use to help me support myself in college.

I guess what I'm trying to say is, I'm glad you're sympathetic and have a sense of outrage about the prison system, and I'm sure that there are places that care less about the kids than where I was. But I want to caution you against being too critical. Juvenile recidivism is a lot lower than adult recidivism. The system works better than you think.