Yes, like alcohol.
Okay... here's the gist of the problem.
Legalizing marijuana will not kill off the drug trade, yes, they will go on and peddle other drugs, but they won't be making as much money as they do now. A lot of people don't consider marijuana a dangerous drug, there's a big underground of recreational users and dealers who have either no connection to the rest of the illegal narcotics trade or a marginal one. Once legalized, these people come to the surface, become legit. The number of growers goes down. It's like alcohol or tobacco... why grow/distill your own if you can buy it at the gas station for cheap? Only hobbyists will be left growing weed.
Alcohol used to be peddled by bootleggers and mafia. When they lost that, some went legit, some just stopped, some went into other stuff. Same thing will likely happen if marijuana is legalized.
The bias against marijuana is mostly cultural, and it makes no sense in a world where you can sniff yourself dead on a tube of superglue or
OD on grain alcohol. (It does happen)
By the way, yes opium is deadly dangerous, but it once was part of daily life for many Europeans and Asians. They didn't die out as a culture... can't say the same about the heavy users, though. I'm not suggesting we should legalize heroin, cocaine, LSD, or the like... in fact, I
feel that we should ban tobacco... but I
think it should stay. I recognize the rights of adults to choose their own poisons.
The Amsterdam model doesn't really work for the rest of the world. It takes a certain cultural attitude to adjust to that, and I don't think we're ready yet.