Well one thing for sure is that while he thinks he is fooling everyone with "having all the cards" (with extras up his sleeve.... the cheater he is)
he's not playing with a full deck. .
I think one reason that Mexico can only do so much regardding drugs and smuggling is because the brutality of the Mexican cartels knows NO boundaries. None. Trump has outright called for their elimination... and although the Mexican gov't can't really do anything... the cartels can. Trump is threatening their business etc.
As for security.... snipers are so old skool. Ironic that because of the US slow walking conventional weapons and ammunition to Ukraine, Ukraine has changed warfare completely with their drones. How easy would it be for El Don Rey Cartelman to organize a dozen of their cartel soldiers to buy and learn how to fly a dozen Mavics and swarm him while he is golfing? They might be limited for a few hours every couple days when he is off the golf course in front of a microphone verbally jerking himself off or signing executive orders with an extra wide Sharpie... but he is predictable when it comes to golfing every day. You know... like Obama.
Personally, I think assassinating anyone is bad for democracy, but I have a hunch that there are plenty of cartel leaders who have given some soldiers drone flying lessons for Valentines Day.