Jhon Velásquez, aka "Popeye," was a brutal killer as head of security for Pablo Escobar, head of Colombia's Medellín cartel until his death in 1993. "People like me can't be stopped. It's a war," he recently told SPIEGEL at his maximum-security prison."You will never win this war when there is so much money to me made. Never." After 40 years of a failed war on drugs, many politicians and experts are started to embrace this same conclusion -- and calling for regulated legalization.