This is true, but you're saying something different than what you started off saying.

I agree with you that the government should be supplying heroin to addicts, and if you're decriminalizing drug usage, there's no reason that you shouldn't be doing this. A doctor having the ability to monitor addicts under their care would give us the means to keep them happy and productive, and to make sure they can get off the drug when they're willing to risk the effort.