The patrol with Rodriguez would serve as a kind of inventory of the advantages enjoyed by the traffickers: cartel engineers who devised methods for circumventing physical barriers; U.S. citizens on the traffickers' payroll who provided logistical support; scouts who meticulously documented the habits of U.S. law enforcement. From Nogales, the county seat, we drove northeast into the Coronado National Forest, passing through the Patagonia Mountains, some of whose peaks approach 7,000 feet. Several signs along the road read smuggling and illegal immigration may be encountered in this area. Now and again we saw trailers and houses. I asked Rodriguez whether he'd be comfortable living there, or even hiking. "Me, personally?" he said. "No."
We turned south, descended steadily, and came upon a handful of singlewide trailers and tar-shingled bungalows. Ahead of us, an arroyo widened into a weedy field, and the road ran under a steel gate. "That's Mexico," Rodriguez said. A derelict sign on the gate faintly read '1975' and 'Lochiel Port of Entry.' Low, anti-vehicle Normandy barriers, recently installed, ran along the border. Rodriguez said that traffickers use flatbed tow trucks to drop dope-filled vehicles over the barriers. They drive over higher vehicle barriers on portable, custom-built metal bridges. When I asked him how much of the Border Patrol's most formidable fencing – deeply anchored steel posts with concrete cores, 30 feet high – protects Santa Cruz County, the fullness and duration of his laugh surprised me. "Not much," he said. Later I got the exact figure: 2.8 miles.
Traffickers know a lot about law enforcement on this side of the border. They see almost everything. They hire U.S. citizens to collect intelligence. A person living on a fixed income in a mobile home in the Coronado National Forest might accept a stack of bills from a stranger if all they have to do in exchange is call a number on a prepaid cellphone when a sheriff's deputy drives by or a Border Patrol technician installs a sensor. Traffickers hire locals to obtain police reports and press releases after major seizures and debrief drug mules forced to drop their loads. They will know which agencies were involved, which kinds of vehicles were used, whether air support was available.
Cartel surveillance teams generally know how long it will take a law-enforcement unit to get from one point to another – they measure response times. They are familiar with the protocols of Border Patrol shift changes. They know that there are fewer agents in the field on weekends. They have mapped everything – all the forest lanes wavering away from the Lochiel gate, for example, as well as the dead-end spur roads. They know whether the Border Patrol has been using trackers in an area and how much lead time a group will need to outpace them.
If a vehicle crossing the border at Lochiel trips a sensor or is otherwise detected and law enforcement responds, scouts direct it onto a spur road, where its driver covers it with brush and a camouflage tarp. (Scouts may also note the potential presence of a new sensor.) Already provisioned for this eventuality, drivers will wait for minutes or hours or days, until the roads are clear.
Traffickers use decoy groups to walk across the border at known sensor locations. Or they may employ banzais, who simultaneously scale border fences and scatter, vacuuming up manpower. Jim Chilton told me that 12 men with assault rifles once marched across the border and straight at a National Guard surveillance post. The men paused while the alarm rippled through the system and then crossed back. As Border Patrol units and tactical teams and sheriff's deputies and helicopters descended on the post, smugglers crossed en masse for miles on either side.
From Lochiel, we headed to the Santa Cruz River, which runs into Mexico about 10 miles east of Nogales. Drug mules often cross the border and hide in the brush along its banks until scouts signal them to continue. We pulled over a few miles north of the border and began walking along the river's south bank until we came to a camp. Amid a jetsam of empty water bottles and bleached shreds of cloth and bits of clothing stood improvised shelters: a lean-to of tarp and driftwood stakes, a canopy of tarp pulled through a lattice of low branches, a roof of viney undergrowth and cardboard on legs of salvaged PVC pipe. We found another camp close by, and then another, and another.
Rodriguez said that traffickers pay locals to resupply people in the camps. He had stopped river-bound cars full of pizza, roasted chicken, and soda, all purchased in bulk from Walmart. In one scenario, a driver picks up provisions at Walmart while three sentinels with cellphones and binoculars station themselves between the store and a drop-off point along the river. If no law enforcement is present, the sentinels authorize the drop and the driver deposits the supplies and leaves. None of these U.S. citizens interacts with cartel traffickers or visibly break the law, and none have information beyond a simple set of instructions for performing a discrete task.