“Anyone who can fly into South America and make their way up to Mexico has a shot at crossing the border and invading America.”
Has a shot?
In my younger hold muh beer moments, I have literally crossed the border illegally twice. Once I walked right through a hole in the fence in Tijuana. The other time I drove across in Arizona, drove to puerto penasco, turned around the next day and drove back into america. A few years after 9/11, mind you. A 3 year old can cross our undefended border, and anybody in mexico that desires to cross into the USA will be nearly unimpeded. This is not an indictment on the border patrol or ICE, just simple mathematics.
There’s a lot of places you can cross over easily, with no checkpoint for up to 100 miles inland.