What to do about immigration, a debate

From LearnLiberty.org, a project of Institute for Humane Studies:

The United States has laws in place to limit the number of immigrants granted entry. How many immigrants should be allowed to call America home? Bryan Caplan, professor of economics at George Mason University, argues that the United States should have open borders. Jan Ting, professor of law at Temple University, argues that there need to be limits on the number of immigrants. Is there a moral argument to be made in favor of allowing more immigrants to the United States? Should immigration policy decisions be based on cost-benefit analysis? What does a cost-benefit analysis say about the number of immigrants that should be allowed entry anyway?