See Japan and Singapore. Also note those two places have the lowest incidence of drug use and homelessness.
It could be because of the viciousness of the punishment. In the US the punishment matches the degree of the crime in the sense that if you sell drugs you get a punishment that you deserve.
In Singapore if you get caught selling over 500mg of weed you are executed via death penalty. The punishment does not match the crime, but rather the punishment is designed to be as effective as possible in eliminating the crime all together via deterrence and Darwinian artificial selection.
Policing DOES work, it's just most people, you included, are drug users. So you want to end homelessness, you want to stop people from over-abusing drugs, but as a casual user yourself you don't want to be put to death either or anything like that so you have to find some middle ground that works. The problem is there is no middle ground. The US drug war was middle ground and as you and your articles pointed out, it was largely NOT effective.
From a personal standpoint I don't use drugs. Morally I'm more of a middle ground type of a person. I think moderation isn't a big deal. Objectively though, since I have no skin in the game, I would support Singaporean measures to stop drugs and homelessness all together.