As I said before, the prohibition of alcohol provides an almost perfect example of what happens when you make a substance illegal and what happens later when you legalize it.
Making a substance illegal has several effects...- Raises potential profit thereby encouraging more people to try get in on the business
- Creates a societal taboo that encourages young people to try the substance out of a typical rebellious phase.
- Encourages the growth of other related illegal activities (theft, prostitution, Gang violence) by and increase in userbase.
- Costs the society in question substantial amounts of time, money, and other resources to "fight" the issue
Having a substance be legal reveals more positive results...- Legalization leads to an increase in the number of producers, lowering prices and creating jobs
- Creates a new form of tax revenue to help improve society in other areas
- More time and resources becomes available for law enforcement to catch truly harmful criminals
- The more casual attitude towards the drug discourages youth from using it as an avenue of rebellion.
The most common complaint about legalizing drugs is that it would encourage more people to use them. Again, if we draw comparisons to the alcohol prohibition we can see that this would not be the case. An arbitrary law has little effect on the habits of an individual in the context of consumption other than affecting the price of the goods in question. Other mechanisms are already in place to discourage the overuse of the substances such as your place of employment, your family and your friends. It is unlikely that any of them would want, nor even allow you to be in a incapacitated state without serious repercussions.
I'll leave the discussions related to the health benefits of drug use to those who have apparently read more about it. The general consensus seems to appear favorable for the legalization of the lesser drugs.
From a purely economical, pragmatic standpoint, the legalization of drugs is a "no-brainer". As it has been said before, the moral opposition to the use of drugs is nonsensical, arbitrary, and hypocritical.