It is very simple logic. If it enters into the stream of commerce then it is a part of commerce. If it doesn’t enter that stream it isn’t part of commerce and needs no regulation. We are talking about the regulation of commerce are we not?
So Congress simply has to use a crystal ball "to know with any reasonable degree of certainty which one will and which one won't" sell pot?
Well, it's an absurd proposition, but it's more than your comrade managed.