For the past two decades the United States, a country with a strong tradition of limited government, has been pursuing a widely popular initiative that requires one of the most ambitious expansions of government power in modern history: securing the nation's borders against illegal immigration. Congress and successive administrations--both Democratic and Republican--have increased the size of the Border Patrol from fewer than 3,000 agents to more than 21,000, built nearly 700 miles of fencing along the southern border with Mexico, and deployed pilotless drones, sensor cameras, and other expensive technologies aimed at preventing illegal crossings at the land borders. The government has overhauled the visa system to require interviews for all new visa applicants and instituted extensive background checks for many of those wishing to come to the United States to study, travel, visit family, or do business. It now requires secure documents--a passport or the equivalent--for all travel to and from the United States by citizens and noncitizens. And border officers take fingerprints and run other screening measures on all travelers coming to this country by air in order to identify criminals, terrorists, or others deemed to pose a threat to the United States.
The goal is to create a border control system that ensures that only those legally permitted by the government to enter the territory of the United States will be able to do so, and that they will leave the country when required. The ambition of such an undertaking is little appreciated. For most of its history, the United States had only the loosest sort of border controls. Scrutiny of most visa applicants was cursory; few checks were done on incoming airline passengers; and it was possible to walk freely across almost any portion of the more than 7,500 miles of land borders with Mexico or Canada (Alden 2008).
That began to change gradually in the 1980s with the increase in illegal immigration from Mexico, and then more rapidly in the early 1990s following a political outcry from U.S. border states, especially California. The border control effort was greatly accelerated after the 9/11 attacks, becoming the primary mission of the new Department of Homeland Security (DHS) created in 2003. Yet some two decades along, border control remains a work in progress. Most Americans remain unconvinced that border security is improving; a Rasmussen poll taken in May 2011 found that two-thirds of the public believe the border with Mexico is not secure. While budget constraints will slow the extraordinarily rapid growth of border enforcement, the Obama administration and Congress are determined to continue tightening border control and further reducing illegal entries.
An in-depth stocktaking of the costs and benefits of this effort to date is long overdue. But at least three interim conclusions can be reached.
First, the U.S. borders are far harder to cross illegally than at any time in American history, and the number of people entering illegally has dropped sharply. Evading border enforcement has become more difficult, more expensive, and more uncertain than ever before. But border control will always remain imperfect; it is not possible for the United States to create a perfectly secure border, and that should not be the goal.
Second, more people still wish to come to the United States-even in a weak economy with high unemployment--than are permitted by current legal immigration and work visa quotas. One consequence is an expanding organized crime problem in which increasingly sophisticated criminal networks earn high returns for helping illegal immigrants enter the United States. This has contributed to a growing sense of insecurity along the borders even as illegal entry has become more difficult. The only way to remedy this is through legal programs that hew more closely to labor market demand.
Third, increased border control efforts have not just discouraged illegal border crossers, but legal travelers as well. …