At Stratfor, THE report you should read on the Mexican weapons trade:
Mexico: Economics and the Arms Trade
At the far end of the spectrum is the black arms market where the guns are contraband from the get-go and all the business is conducted under the table. There are no end-user certificates and the weapons are smuggled covertly. Examples of this would be the smuggling of arms from the former Soviet Union (FSU) and Afghanistan into Europe through places like Kosovo and Slovenia, or the smuggling of arms into South America from Asia, the FSU and Middle East by Hezbollah and criminal gangs in the Tri-Border Region.
Nation-states will often use the gray and black arms markets in order to deniably support allies, undermine opponents or otherwise pursue their national interests. This was clearly revealed in the Iran-Contra scandal of the mid-1980s, but Iran-Contra only scratched the surface of the arms smuggling that occurred during the Cold War. Untold tons of military ordnance were delivered by the United States, the Soviet Union and Cuba to their respective allies in Latin America during the Cold War.
This quantity of materiel shipped into Latin America during the Cold War brings up another very important point pertaining to weapons. Unlike drugs, which are consumable goods, firearms are durable goods. This means that they can be useful for decades and are frequently shipped from conflict zone to conflict zone. East German MPiKMS and MPiKM assault rifles are still floating around the world’s arms markets years after the German Democratic Republic ceased to exist. In fact, visiting an arms bazaar in a place like Yemen is like visiting an arms museum. One can encounter century-old, still-functional Lee-Enfield and Springfield rifles in a rack next to a modern U.S. M4 rifle or German HK93, and those next to brand-new Chinese Type 56 and 81 assault rifles.
There is often a correlation between arms and drug smuggling. In many instances, the same routes used to smuggle drugs are also used to smuggle arms. In some instances, like the smuggling routes from Central Asia to Europe, the flow of guns and drugs goes in the same direction, and they are both sold in Western Europe for cash. In the case of Latin American cocaine, the drugs tend to flow in one direction (toward the United States and Europe) while guns from U.S. and Russian organized-crime groups flow in the other direction, and often these guns are used as whole or partial payment for the drugs.
Illegal drugs are not the only thing traded for guns. During the Cold War, a robust arms-for-sugar trade transpired between the Cubans and Vietnamese. As a result, Marxist groups all over Latin America were furnished with U.S. materiel either captured or left behind when the Americans withdrew from Vietnam. LAW rockets traced to U.S. military stocks sent to Vietnam were used in several attacks by Latin American Marxist groups. These Vietnam War-vintage weapons still crop up with some frequency in Mexico, Colombia and other parts of the region. Cold War-era weapons furnished to the likes of the Contras, Sandinistas, Farabundo Marti National Liberation Front and Guatemalan National Revolutionary Unity movement in the 1980s are also frequently encountered in the region.
After the civil wars ended in places like El Salvador and Guatemala, the governments and the international community attempted to institute arms buy-back programs, but those programs were not very successful and most of the guns turned in were very old — the better arms were cached by groups or kept by individuals. Some of these guns have dribbled back into the black arms market, and Central and South America are still awash in Cold War weapons.
But Cold War shipments are not the only reason that Latin America is flooded with guns. In addition to the indigenous arms industries in countries like Brazil and Argentina, Venezuela has purchased hundreds of thousands of AK assault rifles in recent years to replace its aging FN-FAL rifles and has even purchased the equipment to open a factory to produce AK-103 rifles under license inside Venezuela. The Colombian government has accused the Venezuelans of arming the FARC, and evidence obtained by the Colombians during raids on FARC camps and provided to the public appears to support those assertions.
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