Predicting what may or may not happen in the cannabis market isn't for the faint of heart. The industry continues to face several challenges. A quick look at the charts of some of the largest marijuana stocks over the last couple of years proves it. However, my heart is feeling quite stout these days, so I'll step out on a limb with a prediction. I think Green Thumb Industries (GTBIF 2.77%) stock will double over the next three years. Ridiculous? Not really. About as blue chip as it comes in the U.S. cannab ...