The steel bollards of the U.S. southern border barrier rise in a tight line, each one a tall column of steel filled with concrete and meant to stop a person crossing on foot. For a smuggler with the right tool, they take minutes. The right tool, as agents along the border learned, costs about five dollars.
A tungsten-carbide cutting disc mounted on an angle grinder, a handheld power tool sold at any hardware store, can slice through one of the bollards in a matter of minutes, according to border officials. The cut is narrow, and the smuggler uses a standard car jack to bend the steel aside, opening a gap wide enough for people to pass through. The repair crew arrives, welds the bollard shut, and the smuggler returns the next night with a fresh disc.
The practice was first documented systematically by a reporter for The Washington Post, who obtained an internal Border Patrol memo and reported on it in November 2019. The memo described the technique in the dry language of field observation: the grinder, the disc, the jack, the gap. What the reporting established was that the barrier was not the impenetrable structure its promoters described, but a fence with a recurring, cheaply exploited weakness.
The economics of the attack are what make it persistent. A barrier meant to be climbed over or dug under can be countered with sensors, patrols, and taller steel. A barrier meant to be cut through can be countered only by making the steel harder or by catching the cutter in the act, and the five-dollar disc is replaceable at a rate no construction budget can match. Deterrence, in this arithmetic, is a matter of time and inconvenience, not of impossibility.
The bollards themselves were engineered to resist exactly this threat, and the engineering illustrates the limits of fixed defenses. Each bollard is a steel column filled with concrete and anchored in a foundation, designed to withstand cutting, torching, and ramming. The tungsten-carbide disc defeated that design not by force but by economy: the tool is cheap enough that the cutter can abandon it after a single use.
The barrier itself was the product of a political argument that consumed Washington for years. Its supporters described a wall as a physical guarantee of security; its critics described it as an expensive symbol. The tungsten-carbide disc cut through the argument as cleanly as it cut through the steel, giving both sides a fact to cite and neither side a resolution.
The construction effort had been enormous. Over the course of several years, hundreds of miles of new barrier were built at a cost measured in the billions of dollars, much of it replacing older, lighter fencing with the steel bollard design. The bollard wall became the signature of the program, and its vulnerability to a hardware-store tool became the signature of the program’s critics.
Border Patrol agents have long understood that a fence is a tool, not a solution. The agency’s own doctrine treats physical barriers as one layer in a system that includes sensors, cameras, roads, and people. The November 2019 memo was notable less for revealing the technique, agents had seen it, than for making it public, and for attaching a price to the countermeasure that any smuggler could afford.
The steel used in the bollards is hard, but tungsten carbide is harder, and the disc’s cheapness is the point. Where a smuggler once needed acetylene torches or specialized equipment, the modern approach requires a trip to a hardware store and a power source, both available near the border. The barrier, in this sense, did not raise the cost of smuggling so much as relocate it.
Officials who defended the barrier argued that cutting takes time and noise, and that sensors and patrols can respond before a gap is fully exploited. That defense was accurate as far as it went, but it conceded the central point: the wall’s function was not to stop determined smugglers but to slow them long enough for something else to stop them. The disc reset that equation, because the cut took less time than the response.
The repair cycle that followed became a small, permanent industry. Maintenance crews patrol the barrier, welding closed the cuts as they are found, and the backlog of repairs is itself a measure of the pressure against the structure.
The public reaction to the November 2019 reporting split along predictable lines. Critics of the barrier saw confirmation that the wall was a poor investment; supporters saw evidence that even an imperfect barrier imposed friction, slowing crossings and channeling them toward areas that are easier to patrol. Both readings could be supported by the same memo, which is one reason the dispute never settled.
The deeper point the reporting made was about the nature of border infrastructure. A wall is a fixed object facing an adaptive adversary, and the adversary’s tools improve faster than the wall can be rebuilt. The tungsten-carbide disc was not a secret weapon; it was a commodity item applied to a structure that had been sold as a final answer.
In the years since, the technique has remained a fixture of border enforcement, and the barrier has been modified and reinforced in response, with the two sides locked in the same incremental contest that defines all fixed defenses. The smugglers cut, the crews weld, and the price of the disc has not meaningfully changed.
The episode endures as a case study in the difference between a structure and a strategy. A wall stops what it physically stops, and nothing more; everything else is deterrence, patrol, and the willingness of people to keep trying. The five-dollar disc made that distinction impossible to ignore, and it did so with a tool that fit in a jacket pocket.
