The Mexican drug cartels are finally meeting their match as a wave of cannabis legalisation efforts drastically reshapes the drug trafficking landscape in the United States. It turns out that as states legalise cannabis use and cultivation, the volume of weed brought across the border by Mexican drug cartels dramatically decreases — and is putting a dent in their cash flow. A newly-released statistical report from the U.S. Border Patrol shows a sharp drop-off in cannabis captured at the border between the United States and Mexico. The reduction in weed trafficking coincides with dozens of states embracing cannabis use for both medical and recreational purposes.