How much are Mexico's brutal drug cartels worth?

Thearrest of the head of one of Mexico's drug cartelsis a major coup for the Mexican government, which has been desperately trying to gain an upper hand in its longstanding battle against the countrys drug trade.

Miguel Angel Trevino Morales, leader of the Los Zetas cartel, was captured at dawn on July 15 by Mexican Marines who waylaid a truck with $2 million in cash outside the border city of Nuevo Laredo.

• Ruthless and powerful Mexican drug lord captured

According to U.S. intelligence firm Stratfor, Trevino's arrest "could change Mexico's criminal landscape substantially if Los Zetas begin to unravel in his absence."

Here's a closer look at Mexico's inscrutable, though notoriously brutal, drug trade.

What it's worth

Drug production and trafficking have gone on in Mexico for decades, but the country's role as a supplier has grown considerably in the 2000s, due to U.S. anti-trafficking operations in Florida and the Caribbean, which opened up opportunities for the Colombia-Mexico-U.S. drug corridor.

Mexican drug trafficking is estimated by analysts to be worth $13 billion US a year.

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A report from the U.S. State Department estimated that as much as 90 per cent of all cocaine consumed in the U.S. arrives from Mexico, while the 2013 World Drug Report by the United Nations Office on Drugs and Crime says Mexico is now the biggest producer of opium in the Americas.

Casualties

Turf wars between regional cartels have led to widespread violence in Mexico analysts estimate that since 2006, 70,000 people have been killed in drug-related violence. While the overwhelming majority of victims are rival gang members and other individuals caught up in the drug trade, a significant number of the deceased are members of the Mexican media.

The Zetas cartel in particular has a reputation for intimidating journalists and social-media users to dissuade them from publishing details about local drug activity. The New York-based Committee to Protect Journalists reports that in Mexico, more than 50 journalists have died or disappeared since 2006.

The major cartels

Los Zetas

According to a 2012 report by Stratfor, the Zetas are the biggest cartel in terms of geographic reach. Based in Nuevo Laredo, in the northeastern state of Tamaulipas, their area of influence includes the states of Veracruz, Chihuahua and Oaxaca.

Named after their first commander, Arturo Guzman Decena, who was known to police as "Z1," the Zetas were formed in 1999 by commandos in Mexico's elite army who had gone to work as the paramilitary wing of the Gulf Cartel. The Zetas broke away from the Gulf Cartel in 2010.

The Zetas are known for their brutal tactics, which include torture and beheadings. On several occasions, the group has strewn the mutilated bodies of its victims on Mexican roads and highways to scare rival gangs, particularly the Sinaloa Federation.

The capture of leader Miguel Angel Trevino Morales on July 15 follows the death of another leader, Heriberto Lazcano, who was killed by marines in October 2012. While this will likely lead to some organizational instability, Stratfor notes that the Zetas have often been quick to replace deposed leaders.

Sinaloa Federation

Named after the state on Mexico's Pacific coast that has a long history of drug trafficking, Sinaloa has long been Mexico's largest and most powerful cartel. Los Zetas now operates in 17 states to Sinaloa's 16, but Sinaloa remains powerful. The two groups are the biggest combatants in Mexico's drug turf war.

The cartel is led by Joaquin "El Chapo (Shorty)" Guzman Loera, who up until 2013 had the distinction of being both on the U.S. most wanted list and the Forbes list of the world's richest people. (According to the editors at Forbes, Guzman is "one of the most powerful people in the world, but no longer someone we are confident enough to call a billionaire.")

U.S. authorities have called him the "world's most powerful drug trafficker" and his arrest carries a $5-million bounty.

While the cartel is not above the violent tactics of the rival Zetas, Sinaloa is better known for buying off government and military officials, according to Stratfor.

Gulf Cartel

This once-powerful organization has lost influence since the arrest of its leader, Osiel Cardenas Guillen, in 2004. Like the Zetas, the Gulf Cartel is based in Tamaulipas, and the two cartels have been engaged in a bloody turf war there, as well as in two other northern border states, Nuevo Leon and Coahuila.

The arrest of several of its leaders, who sought refuge in the U.S. as a result of an internal power struggle, has further weakened the group.

Juarez cartel

The influence of the Juarez cartel has diminished in recent years. The rival Sinaloa cartel succeeded in killing one of its leaders, Francisco Vicente Castillo Carrillo, and has made incursions into its control of the Juarez drug route. Stratfor reports that the Juarez cartel still controls the three main points of entry into El Paso, Texas.

Jalisco New Generation Cartel

One of the fastest-growing cartels in Mexico, the Jalisco New Generation Cartel has been allied with Sinaloa, which has used Jalisco as a paramilitary group in its fight against the Zetas.

What distinguishes Jalisco from other cartels is a seemingly principled stand on how it conducts business. Although involved in violent massacres, it has been known to leave behind written messages with slogans such as "No more extortions, no more killings of innocent people!"

Government response

In 2006, then Mexican president Felipe Calderon launched an aggressive anti-trafficking campaign, in which he deployed more than 50,000 troops and federal police to battle the cartels. While many gang leaders were either arrested or killed, overall drug violence rose significantly under his administration.

The failure of Calderon's drug policy is seen as one of the reasons his National Action Party lost the 2012 election to the Institutional Revolutionary Party under Enrique Pena Nieto.

Nieto has pledged to take a more measured approach with the drug cartels by creating a national police force to combat the violence, and has publicly opposed the presence of armed U.S. agents in Mexico.