Health: The numbers are that tobacco and alcohol create problems that are causative in some 400,000 deaths per year, each. The only number I've ever read--and although it was some years back, it was at a time when the alcohol/tobacco numbers were similar to the above--is 30,000 deaths related to drugs.
Deaths from drug-related crimes are not all that high, as the US total for all reasons is around 50K per year. Lotsa publicity, though.
If you're past mellow in smoking pot, I guarantee you that driving is an extremely difficult chore. If you can keep your speed all the way up to legal, it's hard to concentrate on staying in your lane. If you work hard at staying in your lane, it's hard to remember to push on the gas pedal. Why do you think so many traffic stops result in a marijuana bust? The guy was doing 15mph in a 40mph zone! Dang car idles 15mph!
FWIW, the old days' 15-mg spansule of time-release Dexedrine was much better than a line of cocaine for being able to stay awake at a party. Much better. No rush, true, but you can get as much rush as you need from beer, bourbon and more importanly, some Sweet Young Thing.
And if the party isn't all that great, you can go on to bed and actually go to sleep. Your little eyelids don't go Sproink! and stay open whether you want them to or not.
Oh well. The sun's not even up, yet, and I already have quail on my porch...
, Art