Hey man free market. Supply and Demand. People wanna get high, let em get high, make some tax dough at the same time. Don't want Crack or Coke? I'll settle for Weed. We can save billions on that alone because we'd then be freeing millions of non-violent offenders who got caught with Weed, the weakest drug you can buy with 0% death count. It's practically legal now.
And when it comes to illegals the best way to send them packing, is to change our Foriegn Policy that allows US Corporations to rape Mid and South American countries for resources, not to mention our drug war that is an undeniable failure that's costing us Trillions (that includes hidden costs and externalities). Do those 2 things alone and South America will fix themselves. They will create their own economy based on their needs not US needs.