kind of funny but just reading a ray Bradbury story called " the rock cried out". about a couple in central America on vacation. when nuclear attack befalls north America, they are typical arrogant American's don't speak the language criticize the local customs such siestas being lazy. it's about their attempt to return home. i love Bradbury's subtle politicizing and overt like Fahrenheit 451 and subtle like "on the other foot. my point being all things are temporary and there may come a day when north America is is no longer habitable either through natural disasters such as the Yellowstone super volcano, or economic disaster or combination like the dust bowls of the 30's so not a good idea to seal yourself off and build walls kind of like buying a car without having a license. just food for thought
-Louie