Open borders - What if immigration were unlimited?

In 'Open Borders: The Science and Ethics of Immigration', libertarian economist Bryan Caplan & illustrator Zach Weinersmith make the economic case for unlimited immigration. The graphic non fiction book argues it is affordable and even increases global wealth, expressed in terms of gross world product. That's because government regulation and restriction on immigration has an enormous dead weight cost. So what would such a regime look like and why is the case for open borders stronger than the prioritization of high-skill immigrants? Bryan Caplan is a professor of economics at George Mason University and a regular blogger at EconLog. He's also the author of three previous books: 'The Case Against Education', 'Selfish Reasons to Have More Kids', and 'The Myth of the Rational Voter'.