Lieutenant Palmer, the head of the Pima County Border Crime Unit, arranges for me to fly with his helicopter team down to the border. It is an instructive flight. Most of the U.S.-Mexican border in the county is part of a Native American reservation, so in practice the unit only has to worry about thirty miles of the border—but what miles.
Smugglers coming across the reservation have crossed into the department’s sector and the area the Border Crime Unit covers is laced with desert trails that wind through deep ravines. From the air it is not hard to pick out which trails are being used by the illegal border crossers. They are pot marked with spots littered with empty water bottles and trash that glisten in the noon-day sun.
The cartels are a lot more careful. They’ll hold up in the desert, camouflaging their campsites and charging batteries for their radios off portable solar panels. They can loiter out there unseen for days. Some times they get a little hungry for the comforts of home. “When you are out in empty desert,” one deputy told me, “and you come across a couple of sacks of McDonald double cheeseburgers and cases of bottled water, it is not hard to figure out what is going on.” Somebody is doing a resupply drop for a hide-site.