This Thursday, April 20, marks the annual unofficial holiday celebrated around the world by marijuana users. And this year, "4/20" will be observed while America's burgeoning legal cannabis industry sits at a crossroads. Public opinion polls indicate that support for marijuana legalization is at an all-time high in the U.S., and November's election saw four new states vote to legalize recreational cannabis while another four states legalized medical pot. As a result, a majority of the U.S. population lives in a state with some access to legal marijuana. However, cannabis remains illegal on the federal level, and the new administration...