MEXICO CITY Mexico's new president has vowed repeatedly to demilitarize the campaign against drug cartels, but thousands of combat troops likely will remain in the field for years to come, spearheaded by U.S.-favored naval infantry.
Enrique Pena Nieto, who took office on December 1, assured the country this month that the army and the navy will be pulled out as soon as civilian police - including a new federal quasi-military force - are capable of taking on the gangs.
His predecessor as president, the conservative Felipe Calderon, said much the same thing through his six years in power, when drug violence claimed over 60,000 lives.
Now, the effort many critics labeled "Calderon's War" belongs squarely to Pena Nieto and he has few immediate alternatives to the military campaign.
"Under my command Mexico's armed forces will continue being a factor of stability and social confidence," Pena Nieto said last week. "Their mission is to achieve a Mexico at peace."
He already has moved to dismantle the controversial Public Security Ministry and transfer its 36,000-member federal police force to the Interior Ministry, a bulwark of his Institutional Revolutionary Party's 71-year hold on power in the 20th century.
Mexico's once-feared intelligence service, which was gutted in the dozen years of rule by Calderon's conservative National Action Party, is returning to the Interior Ministry too.
Yet a new militarized national police force proposed by Pena Nieto and modelled on France's gendarmerie, is likely to take months, if not years, to set up. That leaves the navy's marines as the most trusted force in the fight against organized crime.
Increasingly toward the end of Calderon's term, it was the navy that won plaudits for the government crackdown on the drug gangs, and Pena Nieto appears to have taken note.
The new president appointed Admiral Vidal Soberon as navy secretary, a move that breaks tradition and apparently signals his desire to keep marines at the forefront of the fight.
Soberon, 53, a U.S.-trained and newly minted three-star admiral, was top aide to his predecessor when the navy's closer ties with Washington were forged. His promotion went over the heads of many senior officers, flouting the chain of command.
"His promotion is a positive step forward," said U.S. Representative Mike McCaul, a Republican from Texas and incoming chairman of the Homeland Security Committee. "The Mexican navy is probably the No. 1 enemy of the drug cartels."
Until its dramatic build-up during the crackdown on drug cartels by Calderon, Mexico's navy had been long been in the shadow of the far larger, and more insular, army.
However, some worry that continued exposure to the cartels in their urban strongholds could corrupt the navy, a fate that has befallen police forces across the country and, to a lesser extent, the army.
Once tasked with little more than guarding tourist beaches and navy bases, the ranks of the marines have swelled by 80 percent to 18,000 during Calderon's presidency. They have been deployed along the southern and northern borders, both coasts, and deep into the interior.
"Sadly, many public security institutions, above all at the municipal and state level, have been penetrated by organized crime," said Vice Admiral Fernando Castanon, commander of the naval zone on the Caribbean coast and the border with Belize.
"It doesn't interest us to be operating in Zacatecas or Coahuila," Castanon said, referring to two states where the marines have waged full-scale combat against the notorious Zetas cartel in the past few years. "But at this moment the country needs it. The navy is trying to fill that void."
Under Calderon, Mexico built a tighter alliance with U.S. military and law enforcement agencies to take on the gangs.
Boasting one of Mexico's most respected intelligence agencies, a small but effective commando force and less insular culture, the navy proved a good fit for the tie-up.
"There's no question the navy has gained considerable prestige from this - way beyond their size," said U.S. political scientist Roderic Camp, a specialist on Mexico's military. "I don't expect there to be any change in what they're doing and the role they're playing."
The navy's special forces, anchored within the 1,800-strong 7th Infantry Battalion in Mexico City, have worked closely with U.S. intelligence and military operatives to catch or kill many top drug lords. About 400 of the battalion's best troops - trained by U.S. Navy Seals and other foreign advisers - carry out the most sensitive operations against the kingpins.
"That's what should be given priority," Mariano Saynez, the just departed navy secretary, told reporters recently. "It's about having less violence, avoiding perhaps the massive use of the armed forces. They have to be more select groups."
In the final weeks of Calderon's government the navy notched up so many successes against the cartels, it looked like the marines were waging the fight almost single-handedly.
During a five-week period, marines captured or killed four top capos including the head of the Zetas gang, Heriberto Lazcano, and the boss of the Gulf Cartel, Jorge Costilla, aka "El Coss."
In the words of a senior military official, Costilla's reaction to being captured on September 12 spoke volumes about the pressure he had been put under by the marines pursuing him.
"He said: 'Thank goodness you caught me. It's been five months since I saw my family,'" the official said.
Still, the navy's close ties with Washington apparently has caused tension with the army and other security forces.
The friction was underlined by an attack by plain-clothed federal police on two CIA operatives and a Mexican navy captain riding in a clearly marked U.S. Embassy car near Mexico City in August. Suspected of acting on behalf of drug lords, 14 federal police, including a senior commander, were charged with attempted murder.
Both the navy and the army have struggled with corruption, abuse of power and heavy-handed law enforcement.
In cities like Ciudad Juarez on the Texan border, popular discontent with the army and federal police is rife after a huge, disruptive deployment during Calderon's crackdown. The navy also has run into trouble in cities racked by crime.
"They are nothing but hired killers," contends Maria Eva Lujan, whose unarmed 29-year-old son, Gustavo Acosta, was shot dead between the eyes by marines raiding the family home 15 months ago in the gang-ridden Monterrey suburb of Apodaca. "To me they are worse than the criminals. The worst," she said.
During Calderon's term, the National Human Rights Commission has received nearly 9,000 complaints of abuse at the hands of the armed forces - from torture and robbery to murder and forced disappearances - including more than 1,100 by the navy.
Still, the navy is trusted more than most.
A national survey by the GCE polling firm published in late November showed the navy was the only arm of public security that a majority of Mexicans did not think had been at least partly tainted by drug gangs.
Some Mexicans fear the worst if the navy is pulled out.
Her eyes clouded with tears, a woman last month grabbed a marine by the arms in the colonial city of Xalapa, capital of the state of Veracruz, which has been ravaged by the Zetas.
"We only trust in you," housewife Cirenia Aguilar, 66, said of the marines, accusing the local police of being in the pay of gangsters. "Please don't leave Xalapa."
(Additional reporting by Dave Graham in Mexico City and Anahi Rama in Xalapa; Editing by Kieran Murray and Bill Trott)
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