Yes, that is true because it is illegal so obviously if you want to change that you would have to convince people to do so. However, the fundamental question of whether it SHOULD be illegal or not does not need a strong argument on the legalization side but the criminalization side does needs a strong argument. For example, say that I created a software that allowed me to predict stock prices very accurately. That would be legal as all things are naturally (before they become illegal). I would not need an argument for it to be legal. However, if people had a problem with it and wanted it to be illegal, they would need to have a good argument as to why it should be illegal. This can be applied to any law, like for example rights for african americans. States used to be able to stop them from voting and was legal at one point (you can argue that they did it anyway after it was illegal, but that's not when I'm talking about). It wasn't illegal to stop them from voting (i.e. literacy tests, fees, etc.) until a case was presented and a law was passed because they had a good argument. MJ on the other hand doesn't have a strong argument, for it to be illegal, and is illegal for no good reason so as you said naysayers do need to be convinced, however, fundamentally it should never have been illegal in the first place.... if that makes any sense at all...