If democracy is a social contract, why don’t we allow everybody who is willing to sign it? Why don’t we have open borders for immigration? In their book "Streets of Gold: America's Untold Story of Immigrant Success," Princeton University’s Leah Boustan and Stanford University’s Ran Abramitzky provide insights from big data to explore how immigration shaped the United States by looking at the economic legacies of immigrants and their children. On this week’s encore episode, hosts Luigi Zingales and Bethany McLean talk with Boustan to unpack how immigrants and their progeny have impacted jobs, wages, and housing prices for native-born Americans. Conversely, how do immigrants’ countries of origin overcome obstacles to socioeconomic change when many of their most-motivated citizens leave? Can data move the U.S. immigration debate beyond the current border crisis?