Marijuana can be ilegal in much places, it is no doubt that how laws and governments act is a big issue...However there are places where a very informal equilibrium exists - Jamaica for example - where Mariajuana is not legal, however you can smell
cigarettes burning anywhere.
Another importan issues is the genetic manipulation of the specie, I've heard/read about artificial kinds of marijuana (synthetic) that cause serious harm even death to those who use it, for instance "K2".
Several aspects should be controlled not only legalization.

Good topic, polemical.
Thank you for share your ideas.