Not only would legalization save billions and empty half of our jails, it would also save tens of thousands of lives around the world from the vicious drug cartels. And the proof is in Colorado thus far.
It is one thing to pass a law, it is another to enforce it. If only a few people disobey it, they can be prosecuted. If many do, the capacity of the courts and, if necessary, the prison system, can be overwhelmed.