While I (as well as others that believe in the NAP, I’m sure) believe the world would be a lot better without violence, this would require no one EVER using force on another, even if it is for the satisfaction of some subjective justice (which may as well be called retribution), and would mean mean there wasn’t only a belief in the Golden Rule, but also a “turn the other cheek” policy. Being only my humble opinion, this is necessary for true, everlasting peace. It would be full faith that the Creator will provide objective justice, without fail, even if it doesn’t satisfy some man’s time-preference.
Now that my two cents is put in, I understand the reason behind your question, “So why should violence (aka “law enforcement”) be used against someone whose environment has led them to act differently than you would like?”
Then again, anyone that uses violence does so based upon their experience in their environment (according to your premises/conjectures). Therefore, someone that seeks, in their eyes, justice, while in the eyes of their aggressor, revenge, through any sort of force from any man or men is merely being a product of their environment, no? That is, there is no way to objectively “justify” the use of force.
I reiterate, this is merely my opinion, especially based upon the premises of the OP.