You know, you really are a moron. Could you grow cotton in Virginia? How about Indigo or Rice in Kentucky? How come those states had the highest slave populations? Could you mine Gold in Alabama. You could in Montana. Could slaves dig gold mines?
You are a sad, sad moron.
But what you could not do is grow cotton in New Mexico until they found a way to build modern irrigation systems, which didn't start being constructed until 1915.
And slaves in mines (if white miners would even allow that) would use hardly any slaves compared to cash crops. It would be a tiny little group and nothing like the fear-mongering people tried to scare people with in the 1850s.