Since 2012, the U.S. has basically ceased policing its southern border.

I had some doubts about this, though ICE numbers show that "removals" have declined from a peak of 410,000 in 2012 to 235,000 in 2015.

"The Department’s clearer and more refined civil immigration enforcement priorities, which ICE began implementing in FY 2015, placed increased emphasis and focus on the removal of convicted felons and other public safety threats over non-criminals."

This sounds like bureaucratic butt-covering for an outcome I welcome: less harassment, especially of people who aren't hurting anyone. It appears that a larger portion of the smaller number of removals occurs at the border. So the CJ summary is not wrong, only grossly exaggerated.

The descriptive term “illegal alien” has given way to the nebulous “unlawful immigrant.”

As it should. "Illegal alien" is nonsense. The plaintive cry that "a person can't be illegal" happens to be true. Are you an "illegal motorist" if you drive 70 mph? No, you're a person who is late for work and made a decision based on your incentives of personal gain weighed against law enforcement patterns.

This, in turn, has given way to “undocumented immigrant,”...

Which has the twin virtues of being factually informative and annoying to people who disagree with me.

Curmudgeons like George Carlin will complain that the language is being diluted, but as happened when "shell shock" became "PTSD" the label is less emotionally appealing and more descriptively accurate.

Since an enforceable southern border no longer exists, there can be no immigration law to break in the first place.

This is a stupid sentence. The border has never been realistically enforceable; we just stuffed plugs into the most conspicuous gaps and made crossing more difficult. The immigration law that matters is that which applies to getting a driver's license and bank accounts, renting or buying a home, and holding a job. If these laws consistently discouraged non-citizens, and were enforced effectively, there would be little incentive to cross the border.

Today’s open-borders agenda has its roots not only in economic factors—the need for low-wage workers who will do the work that native-born Americans or Europeans supposedly will not—but also in several decades of intellectual ferment...

I fear that the rest of the article will neglect the economic factors, and focus on the silly fermentation, because nobody cares about outcomes. In reverse to the usual stance that the possibility and magnitude of a downside is irrelevant if there is any promise of benefit, here the magnitude of the benefit is irrelevant if there is any conceivable downside.

Indeed, Western leftists seek political empowerment by encouraging the arrival of millions of impoverished migrants.

It is a legitimate concern that immigrants can soak up public benefits and influence politics. Here's an idea: don't let them.

Yet the truth is that borders do not create difference—they reflect it.

Please, tell me more about how political borders were drawn — and are updated — to reflect differences in human character.

In ancient Greece, most wars broke out over border scrubland. The contested upland eschatia offered little profit for farming but possessed enormous symbolic value for a city-state to define where its own culture began and ended.

I thought this was an essay arguing the value of borders.

Throughout history, the trigger points of war have traditionally been such borderlands—the methoria between Argos and Sparta, the Rhine and Danube as the frontiers of Rome, or the Alsace-Lorraine powder keg between France and Germany.

Indeed. So if you want to get people to kill each other, just draw a line around them and give them a flag and a song.

Is it merely coincidence that "the most peaceful time in our species' existence" corresponds to the age of multinational corporations, when people around the world benefit each other through trade? Ideas, money, inventions, books, music, food — all flow unhindered from one end of the earth to the other. But human beings are limited to a 90-day stay when they go outside the invisible shape they were born inside.

Barack Obama has caricatured the building of a wall on the U.S. southern border as nonsensical, as if borders are discriminatory and walls never work.

The evidence that a 1989-mile long wall will work must be buried in a footnote somewhere.

Yet the Secret Service is currently adding five feet to the White House fence...

OMG. This is where I bail out. Someone please let me know if there is any discussion of potential benefit — or any tangible positive or negative outcomes — of changing border policy later in the article.