i don't drink or otherwise imbibe either. but i'm with you. legalize it. but continue to enforce EXISTING laws about driving under the influence, continue to allow employers to do drug tests, especially for critical jobs like healthcare, law enforcement, etc. i didn't get a drug test when i applied for a job at DeLorean (irony?) but i did get one when i applied to be an IT guy at the law firm i currently work for. and when i worked as a contractor in the early 2000s, the temp agencies i worked for also drug tested me.
sure, they'd probably have to adjust the drug test tolerances to allow for recreational pot or whatever, since apparently some occasional pot use is fine, just like occasional alcohol use. that shouldn't be too hard.
prohibition didn't work out so well, did it? and now alcohol is legal. i don't see much of a difference here. it's already perfectly legal for a person to buy a bunch of everclear and get completely wasted on it, so why shouldn't they be able to kill brain cells a different way?