Rather than constituting an effective response to illegal immigration, Trump’s insistence on building a border wall with Mexico reflects his unfounded paranoia towards migration in general.

President Trump’s belligerent stance toward Mexico, which has culminated in the recent government shutdown, has undoubtedly played to the president’s nationalist base and probably facilitated short-term political gain. Since he referred to Mexicans as “rapists” and criminals during his presidential campaign, Trump has frequently resorted to maligning his southern neighbour for political gain, impugning it as the source of criminal migrant flows, contraband drugs, and job displacement. In fact, for Trump and his “Build That Wall!” chanting supporters, Mexico has become a scapegoat par excellence, an easy target to explain away the nation’s gravest socioeconomic ills.

The Mexico-bashing has produced tangible political gains for Trump and Senate Republicans. In the November midterms, conservative Democratic Senator Joe Donnelly was trounced in the Midwestern heartland state of Indiana after his opponent tarred him with accusations that a family company had “outsourced” Mexican labor, despite Donnelly’s limited involvement in the firm. Supporters of the Republican opponent, himself an owner of an auto parts company doing extensive business with China, even went so far as to hire a traditional Mexican mariachi band to embarrass the Democrat at public campaign events. Surprisingly, Donnelly’s loss and those of two other Democratic senators in Florida and South Dakota shored up the slim Republican majority in the Senate.

On the immigration front, it is a somewhat strange time for Mexico to be on the receiving end of ad hominem assaults. Since the mid-2000s, irregular migration from Mexico has been on the decline with net migration consistently below zero. The Pew Center in Washington, DC has calculated that 140,000 more Mexicans left than the number that arrived in the United States over 2009-2014, mainly because of a desire to reunify with family in Mexico, slower economic growth in migrant-employing sectors and tougher enforcement in the US interior. Of note, a majority of these so-called “return migrants” did so voluntarily and only 14 percent as part of US government repatriation processes. In contrast, flows from the so-called Northern Triangle countries of Guatemala, El Salvador and Honduras have risen rapidly in the 2000s and 2010s, contributing to almost half of undocumented migrant flows and to majorities of unaccompanied-children arrivals.

The surge of Central American migration has been a major cause of resentment on the anti-immigrant right, spurring spastic polemics and showy enforcement. This was most glaringly demonstrated last fall when a migrant caravan from Honduras set out on the weeks-long journey to the border at San Diego. Unsurprisingly, the ragtag procession of some 5,000 men, women, and children was covered in near-apocalyptic terms by the right-wing media. Meanwhile, the administration bombastically hyped the security threat the group posed because of the alleged presence of some gang members in the throng. Renegade citizen militiamen even proceeded to the southern New Mexico border to volunteer their services, as the destitute band wended its way through Mexico. The administration’s shocking deployment of troops to help stop the caravan from entering the United States capped the extremist rhetoric and media angst, in a decision widely condemned as political for taking place on the eve of the November midterms. The spectacle finally culminated with a police action against caravan members after they allegedly rushed a US processing station near San Ysidro, prompting agents to respond with non-lethal repellants. The entire event was memorialised globally in shared images of women and their crying diapered toddlers escaping active teargas canisters.

The anti-migrant rhetoric has fueled policy decisions that adhere to the mantra of “attrition through deterrence,” or the idea that the volume of migrants may be gradually eroded through a mix of enforcement actions designed to reverberate back to the home country and stem outflows. Besides the showy toughness of the troop deployment and the border police action, one of the most controversial of these has been the administration’s decision to detain migrant children separately from their parents, and to hamstring the administrative processes to slow the pace of asylum hearings. This policy, which drew massive backlash and legal challenges, appeared to have little purpose other than to punish asylum-seekers, while compounding a humanitarian crisis and straining the staff members and capacities of the various government agencies.

The nearly 2,000-mile border separating Mexico and the United States has disproportionately been the site of the government enforcement actions. A majority of the child detention centers were located along the Southwest border for obvious reasons and it has been ground zero for the build-up of security personnel. The rugged borderlands have also taken on a political valence as a heroic last line of defence against “aliens” and all that they may represent in the Trumpian imaginary. So it is unsurprising that in this charged political climate, serious consideration has been given to the once-unheard-of idea of a sea-to-sea barrier, or what Trump has in the past referred to as a “big, beautiful wall”, the funding of which is the source of contention that has led to the ongoing partial government shutdown. Frankly, whether or not a comprehensive wall, fence, or other unbroken physical barrier actually gets built and, then, properly staffed and maintained almost seems beyond the point. The “wall” has already exacted high costs in the form of suspended payments to furloughed federal workers caught in the crossfire of the congressional debate over its multibillion-dollar initial cost. Workers currently ordered to stay at home or work without pay paradoxically include airport security staff and even Coast Guard personnel. But in the Trumpian worldview, with its deep fear of impending swarms of migrants, not just from Mexico but Central America and the greater Global South, perhaps such intransigence would appear rational.

Robert Donnelly is a consultant on Latin American and US-Mexico issues. He was formerly Program Associate for the Mexico Institute at the Wilson Center.

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