The point about prison is that it protects the public from dangerous people. That is a legitimate idea.
I do not care if it is a badge of honour. It protects, for a period of time, the general public.
It may not be a deterrent but that says something about the kind of upbringing and depravity of these child offenders. By the time they have harmed someone with a knife it is too late. Knife carriers are dangerous. That it is why it is a criminal offence.
The other thing is this; this is a youth crime. It's done by the young. People above 25 largely do not commit these type of crimes with anything like the same type of frequency as teenagers.
People talk about prison as a nasty place. Yes it is. I have been to a few. But that is where violent people and people who carry knives deserve to be.
Regrettably over years in the criminal justice system I have seen rehabilitation rise as an aim and dominate youth justice all very well and it's part of the law but I would put violence in a different category. The actual law is failing because it does bit address that for some gangs, it's far better to have children carry weapons or run drugs because of lower penalties. Gangs exploit children and they are setting the agenda in terms of "protection".
There would be absolute uproar if knife carriers all went to prison; parents and youth outreach but the truth is that is failing. These offenders would be off the streets. It's not the only answer but will start to protect society. Oh that level, prison works.