It is in Medellín that I find the best example of the Colombian miracle of regeneration. I arrive at Cepar, a school where both reinsertados and the victims of their violence receive schooling and vocational training that hold the key for possible government funding to restart their lives. In the room in which we are meeting is a poster featuring a favourite success story: a skinny young man stands in front of caged birds and holds quail eggs in his hand, instead of the AK-47s of his previous life. Sitting before me is an array of men, from teenagers like Wilson Castaño (former AUC), with spiky gelled hair, and William Miraldo, who shifts periodically to try to conceal the numerous tattoos under his red shirt, to the middle-aged Jairo Gómez, who lost a son to the AUC and thought the Left was the answer. All of them finished their schooling around the age of ten and have been driven here by desperation and the slaughter of loved ones. 

The hooded eyes and tired, impassive expression on the broad, fleshy features of Diego Fernando Hurtado Loriza, a 25-year-old victim of violence who is on his first day at the school, light up with remembered agony as he tells me how three of his brothers were murdered by the warring factions. Five years ago, when he had a child and heard of Christ, he decided to turn away from drugs, he says. "Christ forgives everything and He taught me to forgive. I encourage everyone here to learn that lesson." He now works with his mother in her biscuit bakery and wants to study to help her grow the business.

While a few of them decided to turn their lives around after the birth of children, this is not the case for everyone. Luís Edison Gavíria Jaramillo is 27 and has nine bullets in his body, one for each year he was a bush-dwelling paramilitary. "I didn't quit," he says. "I was part of a political deal." Such is the reality of the Justice and Peace Law. But even the unrepentant Luís, who must have committed many an atrocity, is a victim of violence. Returning to his family farm from visiting a neighbour, Luís's younger brother passed some guerrilleros. He found their father's body, his tongue, nose and eyes gouged out with machetes. "They tortured him," Luís says, "probably in order to find me."

Uribe would like to demobilise the shrinking Farc as well, under a deal similar to that he granted to the AUC, but the Farc have yet to respond to his condition that they cease all illegal activities for four months. But Medellín is living proof that Uribe's policies work. The city's Comuna 13 neighbourhood was the site of his only urban military assault. Fed by drug money and a steady stream of weapons coming in over the mountains, Comuna 13 was racked by non-stop shooting. In 2003, Uribe took over from the overwhelmed mayor and sent in helicopters, tanks and soldiers to fight an urban battle that raged continuously for a week. Today, I soar over Comuna 13's poorest houses in the world's first mass commuter cable car, which takes them to their jobs in the city's prosperous centre or to the new parquebiblioteca (park-library), where
everyone can surf the internet, read bestsellers or learn of the area's history. Similar schemes are now being tried out in Caracas, Venezuela, and São Paulo, Brazil, transforming Medellín from a global cocaine exporter under the cartels to an exporter of urban renewal.