The U.S. Constitution gives specific powers to the federal govt and leaves the rest to the states via the 10th amendment.
Regulation of Interstate commerce = Federal
Within states (100% Grown, bought, sold consumed within a state) = States rights
besides, the 2014 farm bill already left the issue of industrial hemp up to the states.
and beyond that we get into an age old debate between federalist and states rights.
and even more beyond that, CBD having been found to have "medicinal value" already disqualifies cannabis from being on schedule I by default.
I win. :)