It was only a year ago that exuberance enveloped the marijuana industry. Legalization was spreading and the growth potential seemed boundless. But that bubble has burst as the reality of a difficult regulatory landscape sunk in. Since March, stocks are down by about two-thirds. Capital markets have largely frozen for all but the strongest companies. And now a cash crunch is leaving some on the verge of going bust. Only, thanks to the illegal status of cannabis under U.S.