"This thing causes problems. So, let's make it illegal."
That isn't the obviously good idea you seem to think it is. Outlawing things that people like also causes problems: it criminalizes responsible use as well as irresponsible use; it creates a black market which feeds organized crime; it has been a major factor in the militarization of our police departments, so that now there are lots of little towns with SWAT teams, which do get misused.
There are costs to making these things illegal, and so the question you have to ask is whether the benefit outweighs them. In the case of marijuana, it is increasingly clear that it does not.
That isn't the obviously good idea you seem to think it is. Outlawing things that people like also causes problems: it criminalizes responsible use as well as irresponsible use; it creates a black market which feeds organized crime; it has been a major factor in the militarization of our police departments, so that now there are lots of little towns with SWAT teams, which do get misused.
There are costs to making these things illegal, and so the question you have to ask is whether the benefit outweighs them. In the case of marijuana, it is increasingly clear that it does not.