The Argument for Open Borders

Remember the song "Born Free?"  It's lively and moving (as featured) and pretty much in line with the discussions about the case of getting rid of borders.

According to The Atlantic:

To paraphrase Rousseau, man is born free, yet everywhere he is caged. Barbed-wire, concrete walls, and gun-toting guards confine people to the nation-state of their birth. But why? The argument for open borders is both economic and moral. All people should be free to move about the earth, uncaged by the arbitrary lines known as borders.