That and the tax revenue. A drug lord can sustain his business with high margins because of the high price however they couldn't compete against a major corpor

That and the tax revenue. A drug lord can sustain his business with high margins because of the high price however they couldn't compete against a major corporation producing the same thing even with a higher end tax rate if it was legal. It's the reason why tobacco and alcohol markets are largely dominated by legitimate companies, economies of scale, distribution etc are all in favour of the legal entity (which isn't to say some tobacco and alcohol aren't sold without the tax, nothing is perfect). So legalising drugs is a double whammy, you save a massive expenditure and the war on drugs and increase your tax revenue and force drug cartels into competing with legitimate businesses they simply can't compete with. If I was doing it I'd ring fence the revenue from taxation into treatment and education and put the savings on enforcement either back into the general tax pot or shift the focus onto things like sex trafficking. If nothing else the War on Drugs we have now simply isn't working, it has to be worth trying something else at this point.