My strong suspicion, though I don’t know how to prove it, is that the reason is that marijuana’s a weed, you can grow it in your backyard, so there’s nobody who would make any money off it if it were legal. Tobacco requires extensive capital inputs and technology, and it can be monopolized, so there are people who can make a ton of money off it. I don’t really see any other difference between the two of them, frankly—except that tobacco’s far more lethal and far more addictive.
