Unsurprisingly, prohibition was rooted in racism and xenophobia. It was popular among Mexican immigrants. Before long, Texas cops started telling stories about how it incited violence, gave criminals superhuman strength, and bad Mexicans were giving it to American kids. As an aside, I remember a cop coming to school when I was a kid to teach DARE class and he told us the same thing about PCP. I guess some things never change. Then there was the Reefer Madness movie and the idea that Mexicans would get high and rape white women. Prior to all of this, marijuana had been used by white people - as well as others - to treat all sorts of ailments.