The US Gun Laws Fuelling Mexico’s Cartel Violence

Fentanyl became world news last February. The illegal flow of the drug into the US, where it kills around 70,000 people each year, occurs almost exclusively across the US-Mexico border, and was cited by President Donald Trump as the driving factor behind his plan to impose punitive tariffs on all Mexican goods. But America’s fentanyl problem is abetted by a more pernicious flow in the other direction: that of US-made firearms into Mexico.

The cartel violence that underpins America’s drug trade plagues huge swathes of Mexico. Approximately 20,000 homicides are committed with firearms in the country each year, with around two-thirds attributed to gang-related violence.

Yet Mexico has only one government-run distributor, located on an army base, where it is possible for civilians to buy firearms. And potential buyers must embark upon a long, painstakingly bureaucratic process just to gain the right to purchase them.

To understand how such jarring homicide statistics can exist alongside such tight firearms regulations, we must return to the border. Between 200,000 and 500,000 guns are illegally smuggled from the USA into Mexico each year, and approximately 70% of the firearms recovered from Mexican crime scenes are traceable to the US.

Most of these weapons are initially obtained through illegal ‘straw purchases’ — a process whereby individuals purchase firearms on behalf of someone else. Trafficking networks in the US often employ multiple straw purchasers in order to buy large quantities of expensive, high-caliber weapons without eliciting suspicion. Caches of guns and ammunition are then transported across the border to associated cartels.

The trade of semi-automatic rifles and weapons labelled ‘military grade’ is especially prolific. Guns like the .50 caliber Barrett M107A1, available for around $9,000 from US dealers, can sell for up to $50,000 on the Mexican black market.

This poses significant problems for Mexican law enforcement. The Barrett .50 caliber can penetrate armoured vehicles from over a mile away, and is among the many examples of illegal weaponry that means cartels are often better equipped than the army and National Guard.

The issue is epitomised by a 2015 shootout between the Mexican military and members of the Jalisco New Generation Cartel (CJNG); as four military helicopters honed in on the believed location of CJNG leader Nemesio Oseguera Cervantes, the first aircraft was brought down by two rocket-powered grenades, killing four soldiers (three more were killed and 12 injured in the ensuing firefight). Cervantes escaped and the cartel retaliated to the unsuccessful arrest attempt by setting petrol stations, fire engines, and other civilian infrastructure ablaze in three different states as they terrorised the local population over multiple days, largely irrepressible by law enforcement.

Heavy armament enables individual cartels to dominate entire regions of the country, often repressing the civilian population, and empowers others to engage in bloody territorial wars — usually at the cost of huge collateral violence.

Previous Mexican president Andrés Manuel López Obrador sought to address the cascade of US weapons by filing a $10 billion lawsuit against a number of firearms manufacturers and distributors in US federal court in 2021.

The case, which argued that US gun manufactures like Barrett, Smith & Wesson, and Glock intentionally produce guns for, and market them to, Mexican cartels, are aware of their illegal trade across the border, and even facilitate that trade through specific distributors, was initially thrown out before being heard again in the Supreme Court in June. The latter court agreed that, at the very least, the named manufacturers are aware of straw purchases and the practice of trafficking firearms into Mexico — before unanimously siding with the gunmakers.

The movement of drugs into the US, that has provoked the ire of successive US administrations, is undoubtedly sustained by the reverse flow of weapons. And reports show that many of the people who cross from Mexico into the US illegally — a defining grievance of the current president — do so because they are fleeing violence, extortion, or organised crime largely perpetuated using those same weapons.

So why is the US government so unwilling, or unable, to close the pipeline? The answer can be found in an array of politically powerful interest groups, and the lax laws and poor enforcement whose inadequacy they endeavour to perpetuate.

The US gun industry generates $90 billion per year (including military sales), employs approximately 40,000 people, and boasts some of the country’s most powerful lobbyists. Manufacturers who knowingly profit from equipping both sides in the arms race between Mexican criminals and law enforcement also enjoy the protection of laws specifically designed to minimise their accountability; in the case brought by the Mexican government, lawyers for gunmakers used the Protection of Lawful Commerce in Arms Act (PLCAA) — a law passed in 2005 that shields firearms manufacturers and dealers from liability when crimes are committed with their products.

Enactment of the PLCAA coincided with the end of a federal ban on assault weapons in 2004, precipitating an increase in handgun and rifle production of around 550% and 150% respectively from 2005 to 2022. Coincidentally, in 2008, after more than a decade of declining homicide rates in Mexico, the trend began a sharp reversal. Since then, the US government has spent over $3 billion to help stabilise Mexico and stem the extreme violence south of the border, yet resisted, or been coerced into resisting, any move to regulate the firearms sales that underpin it.

Reluctance to act extends beyond a compulsion to placate firearms manufacturers and dealers. The National Rifle Association (NRA) is not even the biggest political donor among gun rights lobbying groups, yet boasts infamy and political influence well beyond its financial might. Through its tactical allocation of resources, highly engaged network of grassroots activists, and a scoring system that grades US lawmakers on their voting history (and subsequently guides its activists come election time), it wields immoderate power in US elections.

So imposing is the NRA’s political shadow that the Trump administration gave it veto power over proposed measures in its response to the 2018 Parkland high school massacre. (Incidentally, the aforementioned PLCAA has also been used to protect gun manufacturers and distributors in the aftermath of school shootings.) If US lawmakers feel incapable of enacting stricter gun control laws when faced with murdered schoolchildren, what hope is there that violence in Mexico will compel them to act?

Political aversion to regulating firearms sales is further reflected in the enforcement of what few laws do exist. The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), tasked with inspecting firearms dealers and policing the illegal distribution of firearms, is perennially underfunded and understaffed. 

In its 2025 budget submission to Congress, the ATF claimed to have less than half of the industry inspectors necessary to ensure that US firearms dealers undergo compliance inspections every three years. Since the 1986 Firearms Owners’ Protection Act, the agency has also faced a succession of legislative challenges to its authority, curtailing its ability to regulate the sale and manufacture of guns, document their purchase, and conduct background checks on both sellers and buyers. Rumours abound that it will have its powers curtailed further, or even face absorption into another federal agency, under the Trump administration.

Ultimately, this leaves little hope for improvement. Guns will pass from the USA into Mexico, illegal drugs will return, and gangs will continue to impose violence upon the Mexican people. The US gun industry, and the cartels, will profit.

Millions of innocent people on both sides of the border, suffering the consequences of this harmful, tariff-free trade, deserve better.