Of alcohol, tobacco, and pot, it's ironically pot that is the least harmful.
Not to say it's safe, but when there's riots, it's the liquor stores that get looted. It's alcohol that kills tens of thousands every year and thousands of bystanders in drunk driving accidents. And it's tobacco that has cut down millions over the years.
I think the only reason those two were legal was a long history and culture with alcohol, and a huge addicted population with fewer short term effects in the case of tobacco.