What makes drugs attractive to organized crime is profit. Profit requires sales, which comes from demand.
Nothing is being done to address demand. If anything use of these drugs is being encouraged.
But you have to consider that once marijuana is legal, then suddenly the drug cartels have to compete with legitimate commercial growers and distributors. There is limited competition when providing marijuana is a criminal activity. That's what keeps the prices and profits up.
But once the cartels have to compete with a Wal-Mart (for example, even though it won't be Wal-Mart), the increase in competition from legitimate commercial providers severely cuts into the profit to the point where the cartels can no longer afford to compete.
And I think you'll find that the demand for drugs is pretty constant, meaning I don't foresee a huge spike in demand just because it's legal.
Pretty much anybody who is interested in smoking pot can already get it without too much trouble.
Sure, there will be some increase in demand perhaps, but I don't think it will be that big.
“Nothing is being done to address demand.”
Really? How about draconian prison sentences and paramilitary raids on suspected drug users? Generations ago, we had the logic to abandon the War on Alcohol. What makes anyone think this war has gone any better?