Cannabis, or hemp, has been grown in the U.S. since the days of George Washington. KPBS looks at the remarkable history of marijuana in this country, including how it got here, its early reputation for making users violent and insane; and present-day efforts to legalize it. Guests include Richard Bonnie, a professor at the University of Virginia School of Law and co-author of "The Marihuana Conviction", and Isaac Campos, fellow at the Charles Phelps Taft Research Center at the University of Cinncinnatti.