If that was the easy solution then the US would have solved it in the 1990s during the war on drugs.

If prison solved a society's problems, the USA would be a utopia.

The US imprisons more people per capita than any other democratic country, and than most non-democratic countries (only North Korea and arguably China really come close). Unaccountably, it is not a crime-free utopia (it's actually fairly crime-y by rich developed standards).

Putting people in prison has substantial costs.

In my country it was eventually accepted that some people are too far gone. The junkies got their daily ration of drugs until they died of natural causes.

I don't think America is culturally capable of doing that though.