High-tech unmanned drones aren’t just a growing part of the U.S. military arsenal. Drug lords in South America also are trying to utilize modern technology to automate their smuggling of drugs from Colombia to the United States, and even Europe. So far the cartels have had to rely on human-operated vehicles, such as narco-subs — submarines built in the jungle that are dispatched off the coast of Colombia with cocaine and a small crew to rendezvous with ships off of Mexico. The subs have proven to be crudely designed and can take a couple of weeks to travel under the sea, making them vulnerable to accidents, and thus difficult to find crews for.