Shame that so little of it was relevant to what I said.

I couldn't disagree more. Morality is not much of a basis for laws or policy, particularly since morality has a way of being different for different people. To go with your example of drug legalization, the effect on the number of prisoners and advantages of taxation are of course not the only arguments, and are far less important than public health considerations - after all, no sane person wants to legalize heroin. But they are two very important arguments all the same, certainly more important than some vague notion of whether drugs are good or bad.

For your whole not-very-relevant part in the middle: I find it rather ironic that you mention the example of people not wanting to see library hours cut out of principle despite it being wasteful, and generally claim to advocate efficiency and spending based on the results, then turn around and advocate even more jails and police despite the rather damning figures indicating you already have way too many of them. Your point about how sometimes double the expenditure only yields a 50% increase in results works in the other direction too, you know: halve your prison budget and the results will be much more than half as good. Perhaps even better if you spent the saved money in a more useful way.

How you treat prisoners and how you could maybe decrease the chances of recidivism of criminals in prison are important points, too, but the disparity in the rate is so vast that the conclusion you're just throwing way too many folks in prison who never should be there in the first place is inescapable. The fact that some of those people then get into contact with gangs or worse criminals and leave prison worse than they came in, is merely an additional consequence of that main issue, it's not the main issue by itself.