Ive never understood why alcohol is legal and marijuana is not. Now I personally dont drink or smoke now (while not on holiday), but that is a choice which isnt decided on whether something is legal or not. Something like 50% of all arrests are for posession of marijuana, and having smoked my fair share of joints and consuming my share of alcohol while doing my masters in chemical engineering; my opinion that alcohol is way more harmful than marijuana, as marijuana has never caused me to suddenly wake up in the morning and wonder what happened the previous night. If someone wants to use a drug, they use it, the legality of it doesnt change that. That being said, there are a class of drugs such as heroin and crystal meth among others that can be physically debilitating.
I remember reading something about Portugal legalising all drugs, I wonder what the outcomes werein regards to drug use and crime.
Actually, just googled it now and came up with
http://www.time.com/time/health/article/0,8599,1893946,00.html
According to that, it seems to have worked out for them.
I think the issue is a matter of demographics and the state of the various cultures that make up a country.
Because legalizing drugs won't stop at marijuana. Anyone who thinks it will is the world's largest idiot.