From “Black Jack” Pershing’s pursuit of Pancho Villa deep into Chihuahua to fentanyl streaming into the United States, Washington forgets that the southern border has always been a battlefield.

In August, Mexican President Claudia Sheinbaum declared, “We will never allow the US army or any other institution of the US to set foot in Mexican territory.” Her words came after reports that President Trump had signed a directive authorizing the Department of War to conduct military operations against Latin American cartels designated as Foreign Terrorist Organizations, Sinaloa foremost among them.

In Washington the rubric was “hemispheric defense.” In Mexico City it was heard as the prelude to invasion. Both capitals spoke as if the prospect was novel. But it is not.

American forces have crossed the Rio Grande in uniform far more often than most Americans realize. The Mexican-American War of 1846 amputated half of Mexico’s territory. Then, there were the Las Cuevas War of 1875 and the “Bandit Wars,” a series of raids by Mexican outlaws into Texas from 1915–1919. Even the obscure Garza Revolution of the 1890s followed the same logic. When cross-border violence spilled north, the United States answered not with demarches but with dragoons. Mexico remembers. But Americans forget and then declare the next repetition “unprecedented.”

Today’s cartels are not Villa’s cavalry with Mausers. They are diversified corporations of crime with private armies, intelligence capabilities, and global supply chains. Increasingly, they sharpen battlefield skills drawn from contemporary wars. Defense News reported in July that cartel operatives snuck into Ukraine via the International Legion to receive drone training, with the hope of deploying those tactics back home. Their trainers are TikTok and Telegram as much as any jungle camp, and the lessons return home in the form of cheap quadcopters that drop grenades on rivals.

Their signature export, illicit fentanyl synthesized from Chinese-sourced precursors, kills between 50,000 and 75,000 Americans each year. Roughly 450,000 Americans have died from synthetic opioids over the past decade, a death toll that dwarfs U.S. losses in Vietnam. In scale and lethality, fentanyl is closer to hybrid war than banditry. Yet the American debate remains trapped in a prosecutorial frame: indict, extradite, and issue press releases. Meanwhile, the pipeline replenishes itself.

Sheinbaum’s posture is orthodox nationalism. No state welcomes foreign troops, and Mexico, with its long memory of U.S. incursions, least of all. But sovereignty is not merely the absence of foreigners—it is the presence of effective authority. Where criminal syndicates tax, govern, and patrol with heavy weapons, a parallel state has taken root. When that hostile para-state shapes life on both sides of the border, history suggests the neighbor eventually responds.

Here is the awkward truth: even as Mexico swears off a U.S. “invasion,” elements of a U.S. intervention already operate without flags, formations, or ceremony. A recent report in Reuters revealed that for years the CIA has been the gatekeeper of America’s most consequential anti-narco operations in Mexico, working through elite “vetted units” inside the Mexican army and navy. These formations are screened by U.S. polygraphs, trained and equipped with American kit, and financed for travel and sources. They plan and execute many of the high-value captures the public attributes to Mexico alone.

This is not the DEA’s world of chain-of-custody and grand juries. It is the post-9/11 machine of “find, fix, finish” quietly repurposed. Langley leverages signals intelligence to map cartel communications, builds targeting packages, flies drones along the seam of sovereignty, and fuses U.S. interagency efforts from a perch close to the ambassador. Intelligence officers sit on the embassy’s top floor while law enforcement works below.

The January 2023 arrest of Ovidio Guzmán López, a crown prince of Sinaloa, was a case in point: CIA tasking and analytics, U.S. aerial surveillance, a flipped insider, and a Mexican army unit the Agency had long trained and vetted. The colors on the shoulder were Mexican, but the architecture of the hunt was American.

There is historical rhyme here. In the late 19th century, Washington leaned on Rangers, scouts, and ad hoc columns to pacify the border. In the Cold War, U.S. covert power supplied Latin militaries with the means, intelligence, mobility, and money to stabilize their interiors. Today’s version is subtler. Mexico’s civilian leadership publicly shuns the optics of a DEA partnership, then quietly privileges the army and its CIA-vetted cadre as the least leaky vessel. It spares Mexico’s politicians open humiliation and gives Washington an instrument that leaves few fingerprints.

But the pathology is also familiar. Decapitating kingpins’ cartels ignites succession wars and spreads violence laterally. Some 30,000 Mexicans are murdered annually, many in cartel “civil wars” that resemble the internecine feuds of early-modern magnates. This is roughly the level of bloodshed seen in El Salvador and Guatemala at the height of their civil wars in the 1980s. Tactical successes—arrests, extraditions, trophies—stack up while structural conditions worsen. The secrecy that protects operations also shields policy from scrutiny and therefore from correction.

For Trump the politics are brutally simple. Fentanyl deaths dwarf many wartime casualty rolls. Voters see an undefended border and a poisonous supply chain into the country that mocks U.S. sovereignty. Threatening direct action advertises resolve and, not incidentally, distinguishes his posture from a Democratic establishment uneasy about confronting Mexico, let alone Beijing’s role in precursors. The legalists warn of authorities and authorizations. The strategists ask a sterner question: Even if the right exists, can force be applied to decisive effect across a system that stretches from Guangzhou chemical firms to stash houses in Ohio?

Pershing’s columns could raid a bandit camp and degrade the threat. Seizing a Sinaloa lab today is nearer to hitting a node in Amazon’s logistics network. The precursors keep moving, the cooks reconstitute, the middlemen adjust margins, and the product flows.

This is not to say that force is futile. It is to say that force must be nested: financial warfare against cartel and facilitator capital, industrial pressure on precursor exporters, maritime interdictions that treat east-to-west chemical flows as seriously as north-to-south migrant flows, and intelligence-led strikes that deny safe havens. But it is a fantasy to imagine that a single cavalry slash or a wave of missile strikes will extirpate an industry whose demand sits in American towns and whose supply is globally fungible.

Here the Trump Administration’s global fantasies deserve contrast. In September the Taliban publicly rejected Washington’s demand to reclaim Bagram Air Base. The bid was dressed up in Mackinder’s “Heartland” geopolitics—maps drawn for railheads and coal, not fentanyl supply chains and encrypted finance. It reads like a neoconservative reflex: costly, symbolic, remote. The intervention that matters, however, is nearer at hand. The southern border is not a cartographic abstraction but the membrane through which drugs, migrants, and money move daily.

Washington does not need another Bagram. It needs to reckon seriously with Sinaloa.

There is a sober middle course between chest-beating and paralysis. Start with candor: the CIA-led enterprise in Mexico already amounts to intervention by other means, sanctioned by Mexico’s government even as its leaders denounce “invasion.” That reality should be matched to strategy rather than left to metastasize in secrecy.

The United States can insist that vetted Mexican units remain the executors of force while it tightens the rings around the cartels’ money, chemicals, and mobility. It can integrate Treasury’s financial warfare with Coast Guard and Navy interdiction, expand targeted export controls on precursor chemistry, and treat Chinese gray-zone suppliers as facilitators of mass casualty events rather than as mere violators of customs paperwork. Above all, it can consolidate intelligence fusion, not just information sharing, so that every lab raid is linked to a bank seizure and a precursor disruption within the same campaign rhythm.

Realism also demands humility. Tactical brilliance without strategic coherence is caffeinated drift. The Reuters report made clear that Langley’s “find, fix, finish” has not staunched the flood of fentanyl. The kingpins fall, the successors rise, and the funeral homes in America keep long hours. A republic that’s serious about its border will look less like a touring cavalry column and more like an orchestra pit: many sections, one conductor, and a score everyone can read.

When Arturo Rocha, formerly of Mexico’s foreign ministry, said, “This isn’t Afghanistan,” he was right. It is more intimate and more historically entangled. The United States has long treated its southern border as a zone where raiders, revolutionaries, and now cartel magnates test the limits of sovereignty. In earlier eras Americans acted with an often-brutal clarity. Today they outsource decisive action to deniable partners and then wonder why the ledger of the dead continues to climb even as targets are neutralized.

The point of recalling Pershing is not to romanticize punitive expeditions but to remind ourselves that strategy must connect means to ends. The CIA’s invisible auxiliaries have delivered remarkable tactical effects: Ovidio in chains, networks mapped, operations disrupted. Yet a decade’s toll of nearly half a million American dead tells us that tactics without systemic design are the militarized version of the drug user’s dilemma, another hit to stave off the pain.

Sheinbaum draws her red line. Washington counts its dead. The cartels count their profits.

Between the cavalry raid of 1916 and the drone feed of 2025 lies the same question a serious republic must answer: whether it can act with strategic purpose, combining clandestine pressure, economic warfare, and political will on both sides of the border, so that the next repetition of history is not another turn of the screw.