Good Neighbors Can Make Good Fences

But when it comes to Mexico, the United States isn't being very neighborly.

Good fences make good neighbors, or so Robert Frost reminds us in his annoyingly overused and frequently misquoted high school literature class staple. The poem that made the adage famous actually offers a more ambiguous take on the utility of border barriers than its signature line would suggest, with the speaker musing: "Before I built a wall I'd ask to know / What I was walling in or walling out, / And to whom I was like to give offence."

The question of what exactly is being walled in or walled out by Donald Trump's barrier—he issued commands for the "immediate construction of a physical wall on the southern border" in a January 25 executive order—is trickier to answer than it initially appears. The short answer, illegal immigrants, is an unsatisfactory one, in part because so many other goals tend to get lumped in once the policy rationalization process gets rolling, including drug interdiction, terrorism prevention, and tariff enforcement.

The question of who will be offended is easier. From Trump's unflattering remarks about Mexican immigrants while announcing his candidacy in June 2015 to his ongoing insistence that Mexico will pay for the wall, much offense has been given, and much taken.

During the campaign, Trump flew to visit Mexican President Enrique Peña Nieto. Upon returning home, the candidate claimed that they had discussed the wall but not who would pay for it—an assertion his counterpart denied. Shortly after his inauguration, tensions built around a planned visit by the Mexican president to the north. "If Mexico is unwilling to pay for the badly needed wall," Trump tweeted, "then it would be better to cancel the upcoming meeting." When Peña Nieto did just that, Trump made it clear that he would consider garnishing some of the $26 billion in annual remittances from the U.S. to Mexico.

The Associated Press also reported the following astonishing threat by Trump, gleaned from (disputed) transcripts of a phone conversation between the two men: "You have a bunch of bad hombres down there. You aren't doing enough to stop them. I think your military is scared. Our military isn't, so I just might send them down to take care of it." Simultaneously on the table during that period: A 20 percent tax on goods at the Mexican border, though that idea was withdrawn almost as quickly as it was proposed.

When Trump addressed a joint session of Congress on February 28, he reiterated his intention: "We will soon begin the construction of a great, great wall along our southern border," he told the assembled lawmakers. This time, notably, he didn't say that Mexico would pay for it, reportedly as part of a deal he struck with Peña Nieto. The following day, however, his vice president reiterated that this was still the plan. "He didn't say Mexico is going to pay for it," said George Stephanopoulos on Good Morning America. "Well, they are," Mike Pence quickly replied.

In Mexico City in late February, when I visited for a conference sponsored by Arizona State University, the chattering classes were waiting with bated breath to hear whether Trump's capricious treatment of their leader would be returned. Homeland Security Secretary John Kelly and Secretary of State Rex Tillerson were cooling their heels before a planned meeting with the Mexican president. Would they be turned away? In the end, the three men spoke briefly before the American officials returned to U.S. soil.

While the intrigue was titillating, the general sense was that conversations with Cabinet members didn't much matter, because Donald Trump could and would do whatever he liked.

"The only thing that is certain is uncertainty," said El Universal columnist and journalism professor Ricardo Raphael. "Trump talks about renegotiating [the North American Free Trade Agreement] and figuring out Mexico's 'debt' for the wall later, but we have no way of knowing how he will extract what he imposed. Some ways will be worse than others."

That sort of uncertainty is a tax on human activity. It makes every decision more costly. It's expensive for the businessman who is trying to decide whether to move a factory to Mexico but isn't sure whether his goods will be taxed at 20 percent more than anticipated. It's expensive for the migrant worker, who must commit to work for another year without knowing whether she'll be able to remit her paycheck to her family or whether the money will be snagged at the border. It's expensive for drug traffickers, even, who must build ever more elaborate ways across the barrier, not knowing if or when they will be necessary. (For some, this last might be a selling point for Trump's adamant but nonspecific wall policy. It just looks like more deadweight loss in otherwise voluntary commercial transactions to me.)

Part of the uncertainty is how effective a wall will be in the first place. Gaps where "even two can pass abreast" appear in Frost's wall between forest and orchard, though "no one has seen them made or heard them made." They are caused by "the frozen-ground-swell under it," or "the work of hunters" who create places "where they have left not one stone on stone, / But they would have the rabbit out of hiding, / To please the yelping dogs."

Natural forces and people occupied with the business of living their lives will be no more daunted by a border wall than Frost's genteel poachers and apple thieves. As David Bier (page 20) and Theresa Cardinal Brown (page 32) chronicle in our cover stories, the wall will likely function far better as a symbol than as an actual deterrent.

Let's say, hypothetically, that Donald Trump actually manages to get his promised mileage built—opaque, concrete, and 35 feet tall—before the end of his presidency. (Spoiler alert: He almost certainly won't.) Even so, those walls will not be maintained in the gentle collegial spirit of Frost's neighborly builders, who meet each spring to restack stone in semi-mute camaraderie. Border controls executed as erratic, unilateral policy can never be more than expensive failures in the long run—but how long that run will be remains to be seen.

Ronald Reagan's weird postmodern biographer, Edmund Morris, lamented in his book Dutch that the 40th president didn't quote Frost when he visited Brandenburg Gate in 1987; he called the speech Reagan gave instead a "missed opportunity" to deploy the loopily poetic line, "Something there is that doesn't love a wall, / That wants it down!"

But Reagan's unadorned "Tear down this wall," spoken in defiance to a foreign leader anxious to restrain the free movement of people, was Reagan's most lasting legacy, his finest rhetorical hour. I heard an echo of that moment last year, not from a U.S. chief executive, alas, but in former Mexican President Vincente Fox's remarks about shared border infrastructure at the Cato Institute annual dinner: "We should build bridges, not walls. Bridges," he said, "we'll pay for."