What if the government provided their drugs?
Once someone became addicted, they could sign up and then go to government run centres for their free 'fix', whatever it might be on a daily basis. This would ensure clean needles and safe practices. It would eliminate the billions spent on border control of drugs. Crime, prostitution and disease would decrease. Drug cartels would dissolve. It would also remove the supposed 'glamour' of being a druggie.
And, of course, rehabilitation would be offered and provided (free). Most of these individuals use drugs to escape reality and pain. They need therapy and help to handle the bad stuff in their lives.
I think this would save a whole lot of misery for the addicts, and a much safer life for the non-addicted. It would certainly free up a lot of law enforcement time.
It'll never happen, of course.