I don't know how often the OP has had to deal with people high on drugs (especially when they are in a violent/agitated/aggressive state, which is often), but it is bad news. It's extremely unsettling and very hard to deal with. I've seen people rip off clothes, smash out car windows, run at innocent bystanders and scream in their faces like animals, it's crazy. They are almost incoherent and respond to nothing, like they are in another world, or otherwise detached. I think limiting the amount of those people is a good ultimate goal. That said, I think that with legalization, there might be more people using and accessing these drugs, and having uncontrollable responses to them. I've found cocaine, meth, pcp, and other hard drugs to be some of the worst in that regard.

The drug culture, not only the laws are one of the biggest problems. People get roped in, and even after rehab, jail, or treatment, they get out and get sucked back into the drug culture.

Nothing is sadder than to run into a guy with drugs, and have him show you "Great Job" and "Keep it up" type certificates from his rehab center, as well as a graduation certificate, and break down crying, because he is back where he started, back in the drug life and with drugs in his lap. It's a terrible destructive cycle.