The patrol boat, a Boston whaler, was worn at its edges, and it was pocked with bullet holes along its starboard side. It had a four-man crew, officers of the Brazilian Federal Police. They carried AK-47s and side arms, and they wore jeans, sunglasses, and bulletproof vests, which made them sweat. The patrol chief steered the boat into the middle of the Parana River-half a mile wide, muddy, and sluggish. He opened up the boat's two Suzuki engines, and as we moved north the outskirts of the Brazilian city of Foz do Iguacu came into view on the right; on the opposite side was the Paraguayan jungle, where smoke from cooking fires rose above the tree line. The chief, who was worried about snipers, kept the boat moving fast. He pointed to a series of chutes, dug out from the banks on the Paraguayan side, down which drug smugglers move bales of marijuana to the river.

A decaying iron bridge, the International Friendship Bridge, connects Foz do Iguacu to its Paraguayan sister city, Ciudad del Este, the City of the East. Ciudad del Este is at the heart of the zone known as the Triple Frontier, the point where Paraguay, Brazil, and Argentina meet, which has served for nearly thirty years as a hospitable base of operations for smugglers, counterfeiters, and tax dodgers. The Triple Frontier has earned its reputation as one of the most lawless places in the world. Now, it is believed, the Frontier is also the center of Middle Eastern terrorism in South America.
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