Is punishment a reasonable response by the state for crimes. I believe it is more than protecting the society. Punishment provides a deterrent against future time. Punishment of crimes is a state/society responsibility.
IMO, "punishment" doesn't go anywhere. It looks back and generally applies to the unredeemed morality or justice of "eye-for-eye" and not much else. It doesn't look to the future nor does it care. I think the (mis)use of "punishment" is the reason prisons are the go-nowhere, miserable places they are. "Punishment" seems to be the main justification for sentencing and imprisonment. Therefore like punishment, prisons have no vision, no hope. IMO, and I think the record also shows, punishment is an exercise in futility.
As far as deterrents go, I think productive incarceration is as much of a deterrent as anything else, yet it yields potentially positive outcomes. The collateral effects of loss of freedom because of productive incarceration would seem deterrent enough. Why use backward-looking, vision-less "punishment" as a deterrent when forward-looking productive incarceration for protection and relevant payback also serves as a deterrent?
I guess part of what I'm saying is when the prison system revolves around "punishment", then prison, like punishment, becomes a dead-end street, as it is today. But if the prison system revolved around protecting society, productivity, reasonable payback, and rehab, I think we'd see vast improvement in conditions and results. And if someone is "deterrable" (some are not) both would seem to serve that purpose, but one with much better results.
In my opinion, you are ignoring reality.
Step back to smaller crimes. If there was no punishment, can you imagine driving our our highways, trying to keep people from stealing.
Children who don't receive punishment for breaking rules have no sense of control. Too many adults are the same way.
It looks like we are just being repetitive.
It is not enough for a thief to on pay back what was stolen if caught. If there is no consequences to stop the wrong actions society would be overrun with law breakers.
Punishment is, and will always be a deterrent in society. If government fails to provide punishment, eventually groups in society, after being overrun, will rise up and force it to happen.
How do you stop speeding on the highways? Those that give false testimony in court? Fist fights in a bar?