On any given day, U.S. Customs and Border Protection (CBP), the agency within the Department of Homeland Security (DHS) in charge of the nation’s borders, processes almost a quarter-million people seeking to enter the United States through international airports like JFK in New York. Most are like us—people going about their business, seeking to enter the country legally, living ordinary lives. They are U.S. citizens, lawful permanent resident aliens, aliens possessing non-immigrant visas (such as student or work visas), or individuals traveling under the Visa Waiver Program. Some are refugees or asylum seekers. But regardless of their legal status, most mean no harm, and bring significant benefits to our country. Indeed, this massive flow of people across international boundaries—not just the U.S. border—is perhaps the essential lifeblood of the U.S. and global economy. Our prosperity, and the global integration of economies and societies, depends on the unhindered ability of people to move and conduct business around the world, and access, deploy, and nurture talent anywhere....