This is the dumbest idea anyone could ever have. You're a fan of ron paul aren't you? You have the same train of thought as that moron. Do you know how much gang violence would increase if everything was made legal? They would be able to hang out all day pushing drugs without any worry about getting busted, this would lead to more shootings and stabbings as they fight for the best spots to push. And before you say it, I know you are going to say good then they can kill each other, but thats not the case. Far more innocents die when gangs fight then actual gang members.
Then theres the fact that driving while high will skyrocket. Car crashes caused by people being high on weed is already the seconds leading cause in some states behind being drunk. Now you want to legalize dozens of drugs? I also fail to see why you think the violence would be eliminated south of the border. Most of the drugs in the united states are brought here by the drug cartels from mexico. They would still be the number one supplier. The violence would just be brought home.