Is immigration good for America or the World

For this assignment you are to read Chapter 8 “A Radical Case for Open Borders” by Bryan Caplan and Vipuk Niak in the Powell book.  The authors there make a wide ranging case for moving to eliminate national boundaries as limits on.  Our examination of immigration in class has focused on economic dimensions, but in this assignment you can consider all of the different issues raised by immigration.  You can think of this essay as a response to the question, “Is immigration good for America or the World?”  If so, then should there be substantially morethan we currently have, perhaps even to the level of letting everyone move to the country they wish to live in.  If not, then should there be any immigration at all?