A boy runs in El Mango, a rural area in the municipality of Argelia, department of Cauca, Colombia, on June 26. (LUIS ROBAYO/AFP/Getty Images)

If the Colombian government and the country’s largest rebel group finalize a historic peace accord in the coming months, they will set in motion a process of daunting logistical complexity.

The government’s most immediate challenge: to persuade more than 6,000 heavily armed fighters to come down from the mountains, hand over their weapons and start new lives as law-abiding civilians.

The price for failure will be steep. Many of the guerrillas from the Revolutionary Armed Forces of Colombia, or FARC, have been at war since age 14 or 15. Some never learned to read or write. Their previous work experience will make them prized recruits for drug traffickers and criminal gangs but few other potential employers.

The government and FARC have agreed that this process, known as demobilization, disarmament and rehabilitation, or DDR, should begin within 60 days of a peace deal. Precisely how it will happen is another matter. It remains the last major sticking point for the two sides in their attempt to end the bloodiest and most intractable civil conflict in the Americas, one that has hobbled Colombia for 50 years.

Aurora, a former Revolutionary Armed Forces of Colombia member, puts on her prosthesis at her house in Bogota. She was recruited when she was 12 years old and was injured in an attack. (EITAN ABRAMOVICH/AFP/Getty Images)

FARC commanders insist that they will not give up their guns unless they are assured that the government is ready to protect them from myriad enemies: paramilitary groups, drug-cartel assassins and others who might view their disarmament as an opportunity to exact revenge.

For the rebels, demobilization will be a leap of faith, requiring them to cease viewing Colombian soldiers as their enemies and accept them, virtually from one day to the next, as trusted protectors.

The government wants the rebels to leave their strongholds and amass in secure areas it will set up with housing, medical care, counseling and other services. FARC fighters would not have to surrender to government troops and could turn over their weapons to a U.N. group or another third party, Colombian President Juan Manuel Santos said in an interview with The Washington Post.

Santos said he is aware that FARC commanders want no part in a peace-signing event choreographed to look like a defeat or capitulation. He has envisioned a ceremony involving an array of Colombians, which would send a message that FARC will be making peace with society, not just the government or the military.

That will be the easy part.

The rebels are supposed to begin laying down their arms within 60 days of the signing of the peace deal. But the agreement will be subject to approval by the Colombian people through a referendum process, and its different components will require approval from Colombia’s congress. Santos has a majority coalition and is seeking fast-track powers that would allow him to push the peace deal through.

When asked whether FARC would want to hand over its weapons before knowing whether its agreement with the government will hold, Santos said the process could start during the 60-day period but would not need to be completed in that time frame.

“We could begin making an inventory of the weapons and put them in containers,” he said. “I don’t know how long it would take, but we could get started on it.” It is unclear whether FARC would be able to get the weapons out of such containers.

Another question is whether FARC fighters will leave caches of arms in the mountains that they could quickly dig up if the peace agreement falls apart. For rebel commanders to qualify for the “transitional justice” elements of the peace deal — which would allow lesser punishment — they must relinquish their weapons and access to them.

“We know each and every weapon they have,” said Gen. Mauricio Zúñiga, the military commander in charge of the government program that has decimated FARC’s ranks by encouraging rebels to defect.

The program whisks FARC fighters off to resort­like retreats with pools, movies and plentiful food, but it also pumps them for intelligence while they are in government custody. Since 2002, these “individual demobilizations” have taken more than 20,000 FARC guerrillas off the battlefield, Zúñiga said.

Over the years, he said, the program has demonstrated to FARC fighters that they will be treated with respect by Colombian soldiers and afforded protections once they accept their new status as civilians. “We know them: their fears, their interests, their needs,” Zúñiga said. “They’re tired of fighting. They want peace, too.”

According to military tallies, FARC still has 6,230 fighters in its ranks, he said.

Colombian forces have seen no signs that FARC is secretly stockpiling weapons, Zúñiga added, unlike the last time the guerrillas held peace talks with the government in the late 1990s.

Zúñiga challenged the claim that demobilized rebels will grow bored with jobs as construction workers and truck drivers and hire themselves out as gunmen for trafficking groups. “Ordinary FARC soldiers don’t handle cash. They don’t have money,” he said. “It isn’t difficult for them to accept humble jobs.”

Alex Fattal, an anthropologist at Penn State University who is writing a book about Colombia’s demobilization programs, said the government’s track record with mass or “collective demobilization” is far more mixed. It is also fundamentally different for rank-and-file fighters who may be laying down their guns because they are following orders, not because they have had a change of heart.

Many of the right-wing paramilitary fighters who agreed to collective demobilization and entered government rehabilitation programs starting in 2006 have since dropped out, lending muscle to the shadowy drug gangs known as “bacrim” (abbreviated from the Spanish “bandas criminales”), which terrorize parts of rural Colombia.

If a deal is reached, the gangs will look to take over the drug trade in areas where FARC stands down. And they will be hiring.

“If the state doesn’t refocus its vast security resources on the bacrim, Colombia’s law and order problems could get worse before they get better,” Fattal said.

Colombian officials say they are cognizant of the risks and have learned from previous errors.

“We have the tools, the personnel and the territorial presence to quickly deploy wherever we’re needed,” said Esneyder Cortés, the program director for the Colombian Agency for Reintegration, which relocates former combatants and provides them with job training, counseling and other services. The agency has 31 offices and a staff of 900, he said.

Over time, Cortés said, the agency has been increasingly successful at ensuring ex-fighters do not pick up arms again or succumb to the temptations of criminal activity. Since 2003, when the reintegration program began, about 25 percent of its 48,000 participants have committed a crime or returned to guerrilla activity, Cortes said. But the recidivism rate has declined, he added, and last year the rate was 5 percent.

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