Apprehensions along America’s southwest border have plunged in the past decade. Although there have been plenty of stories about it this week, our politicians have yet to grasp this important fact.

From a peak in 2000, the annual number of arrests along our 2,000 mile border with Mexico has plunged by more than 75 percent. Apprehensions are considered a good although imperfect proxy for attempted border crossings. By any measure, the number of people trying to enter the United States illegally between ports of entry has dropped to its lowest level since comparable records began 40 years ago.

A few implications that are not being talked about enough by politicians of either party:

• For those who demand that we must “get control of our borders first” before discussing real immigration reform, that excuse is more hollow than ever. Net migration from Mexico right now is “essentially zero,” according to Jeffrey Passel of the Pew Hispanic Center. This is a political window of opportunity to change our immigration system.
• Immigration reform should be seen as an essential step in reducing illegal traffic across the border. As I’ve noted before, when we have expanded legal immigration in the past, illegal immigration has dropped. The best way to control our border is to expand opportunities for workers from Latin America to enter our country legally through established ports of entry.
• We are in no danger of being flooded by low-skilled immigrants. Yes, beefed up enforcement has played a role in the declining numbers entering illegally, but the economic downturn explains most of the drop off. The Great Recession hit illegal immigrants hard, especially in the construction industry. If the jobs are not available, fewer foreign-born workers come and more go home.
• Conditions in Mexico are improving. Despite bad press about the drug war, staying home has become relatively more attractive for Mexican workers. Thanks to gradual economic reforms, including trade liberalization and the North American Free Trade Agreement, the Mexican economy has enjoyed stable if unspectacular growth. The middle class is growing and poverty is declining. That growth, in turn, has contributed to a plunge in the Mexican birthrate, to where today it has fallen to replacement level.

We should reform our immigration system now. When the U.S. economy recovers to more normal levels of job creation, we will need immigrant workers more than ever. We should be prepared to welcome them legally rather than wasting resources in a futile effort to “control the border” through enforcement only.