I think it was about four, maybe five years ago when the cartels were slugging it out around border towns for control their tactics radically changed. It went from head to head gun fights to more tactical jihadi style combat with the results of being way more mutilated and decapitated bodies. Even some suicide bombers were thrown into the mix. I don't think the cartel's mind very much so long as ISIS is not targeting the cartel's customers in the U.S. and the cartels can learn a thing or two along the way.
Terror tactics may have changed, but they are not new. I read a book that was well more than ten years old describing certain cartel leaders’ behavior. It included horrible murders and mutilations, and a mixing in of certain “religious” elements that were neither Christian or Islamic. I must see if I can find the book and relay the title. The cartels are every bit as vicious as the Islamic terrorists. We need to eliminate their markets by decriminalizing and regulating addiction as has been done to considerable success in places like Switzerland and Portugal. Cartels would then fade and shrink as their money supply dwindled and they could no longer buy Mexican politicians and perhaps some in the US.