Doing drugs should be decriminalized, but not legal. Ideally when someone is found addicted to drugs they would be provided help rather than punishment. Selling drugs should remain criminal but consequences should be determined based on the amount found selling and to who (like a child or someone who's pregnant would be a higher penalty at the discretion of the court), legalizing would just give a tax incentive for pushing drugs similar to gambling.

Edit: I want to clarify, I'm talking about addictive drugs with known negative health effects like meth. Weed can be legal, who cares.