The United States Needs a Southwest Drone Wall

Commentary by Henry Ziemer

Published December 16, 2025

While the Trump administration proclaims a "stone cold closed" border, the airspace between the United States and Mexico remains concerningly open to criminal drones. In 2024, U.S. Northern Command reported that approximately 1,000 drone incursions a month were coming from Mexico into the United States. This year, border patrol agents in the El Paso area report being watched "every day" by unidentified drones hovering just across the Rio Grande, even as migrant encounters along the land border have slowed to a crawl.

Simply detecting these incursions is a challenge for the United States, while neutralizing potentially threatening drones is a whole other challenge. Just south of the border, a recent attack against a Mexican police station in Tijuana that employed an explosive-armed drone underscores the threat these systems pose in the hands of criminal actors.

While Mexican criminal groups have yet to employ weaponized drones on U.S. territory, these unmanned aerial systems (UASs) still help cartels track border patrols, monitor U.S. forces, and deliver narcotics and other contraband. The United States' efforts to curb migrant arrivals at known points of entry have also increased the pressure for organized crime to find new smuggling routes. Drones are a boon to these groups, allowing them to monitor wide swaths of territory and penetrate weak points along the land border.

More broadly, the challenges faced along the border can impart critical lessons for how the United States and its partners might tackle future UAS threats. U.S. policymakers are currently grappling with the vexing questions of how to protect critical civilian and military infrastructure against drone attacks. The lessons learned from securing the skies along the border may therefore be applicable as the United States moves forward with other homeland defense priorities like the Golden Dome. In light of the new National Security Strategy and indications that the Trump administration is doubling down on homeland security, plugging the gaps in border airspace should be a top priority.

Border Challenges

Europe's ongoing efforts to build a 4,000-kilometer "drone wall" capable of detecting and defending against Russian incursions underscores the difficulties of comprehensive UAS defense. The proposal has encountered pushback and disagreement from European Union member states, while the technical complexities associated with rolling out new sensors and countermeasures have pushed timeline estimates back even as Russian drones are probing European and NATO airspace. But these challenges are not insurmountable, and getting border counter-UAS right is not optional for either the United States or Europe.

In this regard, there are good reasons to believe the Southwest land border is a strong test case for area drone defense. For one, the infrastructure is already at least partially in place, with ground and tower-based sensors deployed at strategic points along its length. While this remains plainly insufficient to address the sheer number of drone incursions, the United States would not need to start from zero. Rather than having to achieve consensus among 27 member states, the United States laid much of the groundwork for border drone defense more or less unilaterally. Furthermore, although cartel drone tactics are evolving at a frightening pace, they are still behind those witnessed on the frontlines of the high-intensity conflict in Ukraine.

Despite this, the border remains a wicked problem from a counter-UAS standpoint. At more than 3,100 kilometers long, it is next to impossible to establish persistent surveillance and detection across its full stretch with current capabilities. Criminal networks are also constantly reevaluating and altering their trafficking routes to better evade U.S. patrols, meaning any weak spots will be rapidly discovered and exploited. Deploying the requisite number of sensors to achieve full coverage is not cheap either, while current counter-drone interceptors are often far more costly than the small UASs they shoot down. Meanwhile, the high level of economic integration between the United States and Mexico means that drone countermeasures could be highly disruptive or even dangerous if they make a mistake.

No commander wants to accidentally order the jamming of a commercial airliner's radio or the dazzling of a civilian helicopter's radar. There is also the question of cross-border operations. When a cartel drone is hovering just across the border, spotting U.S. patrols on the other side, can the United States launch a kinetic kill vehicle to take it out? Although the Trump administration has pursued strident rhetoric about bringing the fight to cartels, tactical commanders may be loath to provoke what could become an international incident, even though it means incurring greater security risks.

Another troubling development has been recent reports of cartel experimentation with fiber-optic drones. Now a mainstay on the battlefields of Ukraine, these systems rely on a thin spool of fiber-optic wire to connect the pilot to the drone, providing a connection that is resilient to jamming and other electronic warfare attacks. This further complicates counter-UAS efforts along the border, providing organized crime with a highly resilient tool for surveillance and smuggling.

The use of fiber optics by cartels remains in its infancy, and it should be noted that drone operators face significant tradeoffs when using wire-guided drones. Cabling can get tangled up or severed in complex terrain or even under certain weather conditions. The fact that cartels have begun to experiment with such tools, however, indicates pressures from a more denied electromagnetic spectrum. Most likely, this is the result of intra-cartel competition, as rival criminal groups are not only adopting more UASs but also equipping their gunmen with jamming equipment. Meanwhile, state security forces on both sides of the border risk being left in the dust.

A border drone wall should account for these challenges, placing a premium accordingly on broad area sensor coverage, a wide range of hard- and soft-kill countermeasures, and the development of better deconfliction procedures for civil and military stakeholders.

Safeguarding the Skies

Existing air defense systems often focus on a relatively small number of highly advanced radars. In the future, more distributed, passive networks of acoustic, electro-optical, and infrared sensors will be needed to achieve coverage and resiliency. Unlike a peer adversary, Mexican criminal groups lack a sophisticated industrial base to produce more advanced drones that can evade proliferated sensor networks. This means there is greater room for experimentation when rolling out countermeasures. Indeed, even Russia has struggled to minimize the signature of low-and-slow flying attack drones in response to Ukraine's widespread use of acoustic sensors in its Sky Fortress network. This suggests that a sufficiently large network of passive sensors could have remarkable success in detecting drone incursions across the entire Southwest land border. Achieving the necessary sensor density will also be an important test of U.S. defense industrial capacity and whether production of current systems can be scaled up fast enough.

But detection is only one piece of the puzzle. More challenging still is how to classify and subsequently engage potential illicit drones along the border. Classification is critical to ensure the various inputs collected from sensors can quickly and reliably distinguish between a bird, a drone, and a commercial airliner. The U.S. military is currently working to overhaul its object classification protocols in anticipation of a world where the skies are crowded with more high- as well as low-end platforms. Most of the border drone incursions by criminal groups will likely involve a similar threat profile of cheap, commercial UASs with takeoff weights of less than 20 pounds (known as Group 1 drones in Department of Defense parlance). However, any border drone wall should account for future illicit innovation and the possibility that criminals, or other U.S. adversaries, might seek to slip more advanced and durable drones across the border. Cartels have already been experimenting with platforms like the DJI FlyCart 30, which is capable of moving payloads weighing more than 80 pounds, placing it potentially under the Group 2 or 3 designation. Ensuring that counter-UAS systems along the border can differentiate between these larger platforms and more commonplace small commercial UASs will be vital to future-proof the system.

Once an illicit drone has been detected and its threat profile validated, countermeasures will need to be mobile in order to rapidly reposition and interoperable to share data with the distributed sensor net. Joint Task Force-Southern Border, in partnership with U.S. Northern Command, could provide the backbone for agencies like the Federal Aviation Administration, Customs and Border Patrol, and local police forces to access data from the new sensor network, rapidly validate reports of illicit drone incursions, and deconflict nearby airspace to safely employ kinetic and non-kinetic countermeasures. This could also be a crucial area for Joint Interagency Task Force 401, established this August as a fusion center for counter-UAS efforts, to contribute valuable expertise and capability.

In addition, the Department of Defense should consider designating areas at borderland military bases and zones to install new anti-UAS systems for live testing. Currently, a host of technologies in various stages of development are seeking to provide cost-effective and reliable counter-UAS solutions. The Southwest border can act as a testbed for prototypes to defend against real-world challenges. There are already promising signs that these efforts are well underway. The 10th Mountain Division of the U.S. Army, deployed to the border, has been using the AN/TPQ-53 and AN/MPQ-64 radars to detect small UAS incursions, gathering valuable hands-on data. The army has also rolled out new anti-drone jammers to units deployed along the border to provide additional soft-kill options.

However, while the U.S. military seems to be getting better at securing its fixed installations against drone threats, achieving comprehensive border security demands mobility. Any gaps in coverage will be quickly found and exploited by organized crime. Currently, local law enforcement largely depends on what the military is able to give them for counter-UAS, which is often lacking, given the magnitude of the challenge. Ensuring there are clear and effective lines of communication between local police and border patrol, and the armed forces, will also be important so these units can call up counter-UAS systems quickly when they identify a potential illicit drone. Another key test will be whether the United States can scale up defense industrial production to produce enough sensors to cover thousands of kilometers worth of territory.

Ideally, this model of partnership would eventually bring in Mexican counterparts. The Trump and Sheinbaum administrations have already signed agreements establishing bilateral task forces to work on issues like firearms trafficking and migrant smuggling along the border. Establishing a mechanism to allow counter-UAS assets based in the United States to target drones just across the border would help both countries more effectively combat this emerging threat. This working group could even open the door in the future to technology transfer, allowing Mexican security forces to roll out more of their own counter-drone systems. Although U.S.-Mexico relations are currently characterized by considerable uncertainty on the latter country's part about the Trump administration's threats to use unilateral military force against the cartels, cooperation on drone defense may present an area to reframe the conversation. For Mexico's part, working with the United States to identify and take down cartel drones along the border would not only improve its domestic security situation but also show a willingness to be a partner rather than an obstacle for the U.S. war on narcotrafficking.

While the challenges of establishing a southern drone wall are substantial, investing in drone defense at the border can pay dividends for the United States in the long term. The technological, tactical, and interagency evolutions required to counter waves of cartel drones mirror those that the U.S. military might face, on an even greater scale, in a future high-intensity conflict. Ensuring these are in place sooner rather than later is therefore vital for safeguarding American lives both at home and abroad.

Henry Ziemer is an associate fellow with the Americas Program at the Center for Strategic and International Studies in Washington, D.C.

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