Type 2: Guns Legally Available in the U.S. but Not in Mexico

Many popular handgun calibers, such as 9 mm, .45 and .40, are reserved for the military and police and are not available for sale to civilians in Mexico. These guns, which are legally sold and very popular in the United States, comprise our second category, which also includes .50-caliber rifles, semiautomatic versions of assault rifles like the AK-47 and M16 and the FN Five-Seven pistol.

When we consider this second type of guns, a large number of them encountered in Mexico are likely purchased in the United States. Indeed, the GAO report notes that many of the guns most commonly traced back to the United States fall into this category. There are also many .45-caliber and 9 mm semiautomatic pistols and .357 revolvers obtained from deserters from the Mexican military and police, purchased from corrupt Mexican authorities or even brought in from South America (guns made by manufacturers such as Taurus and Bersa). This category also includes semiautomatic variants of assault rifles and main battle rifles, which are often converted by Mexican gunsmiths to be capable of fully automatic fire.

One can buy these types of weapons on the international arms market, but one pays a premium for such guns and it is cheaper and easier to simply buy them in the United States or South America and smuggle them into Mexico. In fact, there is an entire cottage industry that has developed to smuggle such weapons, and not all the customers are cartel hit men. There are many Mexican citizens who own guns in calibers such as .45, 9 mm, .40 and .44 magnum for self-defense — even though such guns are illegal in Mexico.

Type 3: Guns Not Available for Civilian Purchase in Mexico or the U.S.

The third category of weapons encountered in Mexico is military-grade ordnance not generally available for sale in the United States or Mexico. This category includes hand grenades, 40 mm grenades, rocket-propelled grenades (RPGs), automatic assault rifles and main battle rifles and light machine guns.

This third type of weapon is fairly difficult and very expensive to obtain in the United States, especially in the large numbers in which the cartels are employing them. They are also dangerous to obtain in the United States due to heavy law enforcement scrutiny. Therefore, most of the military ordnance used by the Mexican cartels comes from other sources, such as the international arms market — increasingly from China via the same networks that furnish precursor chemicals for narcotics manufacturing — or from corrupt elements in the Mexican military or even deserters who take their weapons with them. Besides, items such as South Korean fragmentation grenades and RPG-7s, often used by the cartels, simply are not in the U.S. arsenal. This means that very few of the weapons in this category come from the United States.

In recent years the cartels, especially their enforcer groups such as Los Zetas, Gente Nueva and La Linea, have been increasingly using military weaponry instead of sporting arms. A close examination of the arms seized from the enforcer groups and their training camps clearly demonstrates this trend toward military ordnance, including many weapons not readily available in the United States. Some of these seizures have included M60 machine guns and hundreds of 40 mm grenades obtained from the military arsenals of countries like Guatemala.

But Guatemala is not the only source of such weapons. Latin America is awash in weapons that were shipped there over the past several decades to supply the various insurgencies and counterinsurgencies in the region. When these military-grade weapons are combined with the rampant corruption in the region, they quickly find their way into the black arms market. The Mexican cartels have supply-chain contacts that help move narcotics to Mexico from South America, and they are able to use this same network to obtain guns from the black market in South and Central America and then smuggle them into Mexico. While there are many weapons in this category that were manufactured in the United States, the overwhelming majority of the U.S.-manufactured weapons of this third type encountered in Mexico — like LAW rockets and M60 machine guns — come into Mexico from third countries and not directly from the United States.

There are also some cases of overlap between classes of weapons. For example, the FN Five-Seven pistol is available for commercial purchase in the United States, but the 5.7x28 armor-piercing ammunition for the pistol favored by the cartels is not — it is a restricted item. However, some of the special operations forces units in the Mexican military are issued the Five-Seven as well as the FN P90 personal defense weapon, which also shoots the 5.7x28 round, and the cartels are obtaining some of these weapons and the armor-piercing ammunition from them and not from the United States. Conversely, we see bulk 5.56 mm and 7.62 mm ammunition bought in the United States and smuggled into Mexico, where it is used in fully automatic AK-47s and M16s purchased elsewhere. As noted above, China has become an increasingly common source for military weapons like grenades and fully automatic assault rifles in recent years.

To really understand Mexico's gun problem, however, it is necessary to recognize that the same economic law of supply and demand that fuels drug smuggling into the United States also fuels gun smuggling into Mexico. Black market guns in Mexico can fetch up to 300 percent of their normal purchase price — a profit margin rivaling the narcotics the cartels sell. Even if it were somehow possible to hermetically seal the U.S.-Mexico border and shut off all the guns coming from the United States, the cartels would still be able to obtain weapons elsewhere — just as narcotics would continue to flow into the United States from other places. The United States does provide cheap and easy access to certain types of weapons and ammunition, but as demonstrated by groups such as the Revolutionary Armed Forces of Colombia, weapons can be easily obtained from other sources via the black arms market — albeit at a higher price.

There has clearly been a long and well-documented history of arms smuggling across the U.S.-Mexico border, but it is important to recognize that, while the United States is a significant source of certain classes of weapons and ammunition, it is by no means the source of 90 percent of the weapons used by the Mexican cartels, as is commonly asserted.