I think it depends. It depends on the country and society, for example, some European people use drugs and they don't harm anyone, but the people here in Venezuela who use drugs are normally criminals, and it leads them to do bad things because they are already bad people who were raised the wrong way, basically parasites.

I think it's a double edged weapon, because making them legal in the wrong country can lead to an abusive consumption of certain drug and having to deal with so many addicts would be a total problem. On the other hand, making drugs consumption-free would put an end to the organized crime and drug mafias, this means less crimes related to drug selling.

In Uruguay only marijuana is legal, but that's a country with lower crime rates than most countries from America. Of course, Marijuana is not a dangerous drug like many others and people can stop being addicted to it more easily than other strong drugs.

Conclusion: I agree that soft drugs like marijuana should be legalized but only in societies that are prepared for that.