The prohibition of drugs has never been based on a real understanding of their harmfulness, nor of the conditions under which drug use is likely to lead to abuse or dependence.
I think that punishing drug use is ineffective as a deterrent and does nothing to reduce the harmful effects of drug use.
Drug use is as close as you can get to a human universal behaviour, and yet we still operate under the assumption that the criminal justice system will be able to a) protect people from themselves b) address the psychosocial aspects of abuse/dependence.
By imprisoning someone, you are firstly reducing their attractiveness in the job market and impacting on their future ability to sustain themselves.
Furthermore, you put them into an environment where they will be socialised into criminality.
When they leave prison they have little chance of finding work and probably an untreated drug problem.
My proposal is to legalise cannabis and decriminalise the possession of small amounts of other drugs.
Policing should only focus on the supply side.
However, this is only half the problem.
The state of drug rehabilitation clinics in South Africa is quite terrible; there are far too many unqualified people entering into the industry in order to make a quick and dishonest buck.
Fixing this sector is the way to close the loop on the drug problem in my opinion; those in the minority who go on to abuse/become addicted to drugs can only be helped if their psychological/psychiatric health is improved simultaneously.
I propose a similar model to the Portuguese system, whereby drug users are not arrested but if it suspected that they are using problematically they will be scheduled with a social worker/psychologist who can assess their situation and offer a referral to a treatment and diversion programme staffed by qualified professionals.
The resources used to arrest, prosecute and imprison these people can be diverted more effectively in this manner.
On the cannabis issue specifically, rural communities have been farming this cash crop for generations.
They have the skills and the will to pay the bills and should be consulted when the time comes to commercialise the plant.
There are literally hundreds of industrial uses for hemp and cannabis and these will be unlocked.
It should never have been made illegal in the first place, and although not harmless it is certainly nowhere near as harmful as alcohol and tobacco.
It's biggest danger is to those with a genetic predisposition to psychosis and for teenagers as their neural development is not complete (although this goes for most substances too.)