The problem with legalizing drugs is everyone gets addicted to certain things. You never know what you're going to be addicted to or when it happens until it is far too late. Once that happens you can't go back to something "you're not addicted to" or even alcohol because it's just going to become a substitute and soon enough a substitute addiction.
Stopping drug enforcement will just put that many more addicts on the streets and who can't support their habit, not even by dealing now, so they're going to rob more people & property so they can buy more of this one thing they must have at all costs.