Another argument is the incredible damage that drug prohibition has done to our society. Millions of drug users have been criminalised and/or jailed just because they wanted to alter their state of mind. Drugs on the street are often tainted with adulterants. Violent drug cartels have wreaked absolute havoc on entire countries.

The war on drugs does not work, so let's take a fresh approach.

Some people call sugar a poison, some call pornography a poison some people call stress a poison.

Consenting adults not harming others should have the right to poison themselves as they see fit.

GordonS> "Millions of drug users have been criminalised"

Well yes, they are criminals who have broken the law. Your argument is defeatist; drug prohibition works quite well in places like Japan and Singapore.