How do you explain nearly all of Latin America having wild murder rates? All of the most dangerous non-war zone countries on earth are in Latin America. And yet that same murder & violent crime problem isn't represented in Canada. What could possibly explain that consistency across ~15 different Latin American nations, except that it's a cultural and institutional problem? Colombia for example has seen dramatic improvements, despite the US demand for drugs increasing in the last 15 years. Or take Venezuela, one of the most dangerous nations, with a truly shocking murder rate, and it has very little to do with the US drug demand. Or take Brazil, a nation of 200 million with a murder rate 7 to 10 times that of the US (with up to half of all murders unreported in official stats), which also doesn't derive its huge murder problems from the US drug demand.
It's far too simplistic to just blame the US for everything.