The federal government has a duty to enforce this nation's borders and do it in a humane manner that minimizes harm to human life both inside U.S. territory and on the approaches to it.
The best way to do that at the border with Mexico is to build effectively impermeable barriers that send a simple, straightforward message: You can only cross this border legally.
For years, our government has sent a different message: You may be able to cross illegally.
More recently, that inapt message has been compounded by another: If you make it here illegally, we may let you stay.
Between 2005 and 2010, according to the Congressional Research Service, the Department of Homeland Security used a measure called "operational control" to describe the stretches of border it had secured.
"Operational control describes the number of border miles where the Border Patrol can detect, identify, respond to, and interdict cross-border unauthorized activity," CRS said in a report published last month. "In February 2010, the Border Patrol reported that 1,107 miles (57 percent) of the Southwest border were under operational control."
That means our government, according to the Border Patrol, did not have operational control of 43 percent -- or approximately 826 miles -- of our southern border.
By failing to secure the border, the federal government not only allows foreign nationals to come here illegally to live and work, but also provides an avenue for deadly drugs, for the criminals who bring them and for potential terrorists.
The failure to secure our southern border harms American workers whose jobs are put at risk and whose wages are suppressed by competition with immigrant workers here illegally.
It also harms Americans who become addicted to deadly drugs smuggled across the border, and it harms American communities where those drugs are distributed.
"Mexican transnational criminal organizations (TCOs) remain the greatest criminal drug threat to the United States; no other group can challenge them in the near term," the U.S. Drug Enforcement Administration said in its 2015 National Drug Threat Assessment Summary.
"These Mexican poly-drug organizations traffic heroin, methamphetamine, cocaine, and marijuana throughout the United States, using established transportation routes and distribution networks," said the DEA assessment. "They control drug trafficking across the Southwest Border and are moving to expand their share of U.S. illicit drug markets, particularly heroin markets."
"National-level gangs and neighborhood gangs continue to form relationships with Mexican TCOs to increase profits for the gangs through drug distribution and transportation, for the enforcement of drug payments, and for protection of drug transportation corridors from use by rival gangs," said the assessment.
Failure to secure our border not only harms people in the United States, it also harms people in Mexico and would-be illegal border crossers. Mexicans are victimized by the drug cartels that exploit our unenforced border, and migrants seeking to cross our unsecured border to illegally live or work here put themselves at risk in remote regions and in the custody of human traffickers.
The message our federal government should send is: If you are coming here illegally, you will not be able to cross, so do not try.
Building physical barriers along the border that make it impossible for people to illegally pass either on foot or in vehicles -- and deploying sufficient manpower to patrol those barriers -- would send that message. Failing to build those barriers and sufficiently man them says: The people who run our federal government are still not serious about securing our border.
America is a generous nation when it comes to legal immigration.
Between 1980 and 2012, according to a 2014 report published by the Department of Homeland Security, the United States granted lawful permanent resident status to approximately 28,370,000 immigrants.
Those 28,370,000 legal permanent residents equaled more than three times the Census Bureau's July 2013 estimate for the population of New Jersey (8,911,502), more than twice the population of Illinois (12,890,552) and exceeded the populations of New York (19,695,680), Florida (19,600,311) and Texas (26,505,637).
America is also generous in granting refugee and asylum status to those who face a "well-founded fear of persecution" in their home countries. In 2013, this country granted refugee status to 69,909 individuals and asylum to 25,199.
We should not turn our back on those who seek refuge and asylum, especially Middle Eastern Christians who face genocide by Islamic State terrorists. Nor do we need to stop legal immigration.
But the border of the United States is a just law that the federal government has duty to enforce. Building walls that deter and stop illegal crossers is a humane way to do it.