Heck, asprin can be "deadly."
Salt can be "deadly."
Difference is if I take an aspirin and get behind the wheel of a car, I am no more likely to cause an accident than if I hadn't taken the aspirin. Same cannot be said for smoking a joint or having a drink.
I reassert my position that it is reasonable for society to restrict or prohibit the use of products for the safety or it members. While it may appear arbitrary that alcohol is legal, but marijuana is not, such distinctions are based on historical use and cultural norms.
How do "historical use and cultural norms" justify the @ss-backward policy of banning the less dangerous drug while allowing the more dangerous drug?