So take heart, because once the horrific secret truth of how terribly harmful marijuana use is, we'll no doubt reject it thoroughly as a culture.
Until then, we can only hope the devil weed won't claim our children.
It might help if they had a single credible study that recommended it be prohibited in the first place.
I like Schaffer's Library of Drug Policy. They have texts of just about every major study of drug abuse ever conducted, going back to 1894.
Not one recommends prohibition.
Maybe you know of some upcoming studies that will blow them all out the water, but your statistical correlation with mental illness ain't it.