As Uncle notes, Mexico can't control their crime problems,

like grenades and automatic weapons being smuggled in from overseas and countries further south, so they want us to trash the 2nd Amendment.
But the Second Amendment wasn’t adopted by the Founding Fathers to allow transnational organized crime to illicitly buy weapons in the Unites States and be illicitly cross them over international borders into countries where those calibers and types of weapons are prohibited,” the official said.
Oh, like all those aforementioned grenades and RPGs and automatics smuggled from China and Russia and Korea and wherever? And those sold to your military and then sold by corrupt troops and officials to the drug cartels? Those are being 'illicitly bought in the US'?

You know, Mr. 'Official', there's a simple solution: we build an actual guarded wall and fences on the border, and then you won't have to worry about ANYTHING being smuggled in from the US. Of course, then you can't smuggle illegal aliens and drugs and weapons into the US, either. You miserable little bastard.