We're lucky we could catch this guy, happened to be in the USA. This is why, probably the most feasible solution is to seal up the border and try to make sure nothing gets through, the border, the sea, whatever points of interest they could use.
Most of us realized that almost 20 years ago during W's administration. That IS the reason that Trump was elected. He PROMISED to build a wall and to change immigration and asylum laws. People wanted their country back and were tired of the BROKEN promises by the GOPe.
As for the cartel corruption going all the way to the top. The U.S. is not without corruption as far as the war on drugs; our own border patrol is riddled with corruption as well as some of our politicians.